What does each Zephyr service cost on a Teensy 4.1?

Flash and RAM cost of the modules of a small Zephyr reference application, and of 279 Zephyr services: networking, storage, security, OS services, drivers, USB classes and field buses. Each number comes from a full clean build for the teensy41 board (NXP i.MX RT1062, Cortex-M7, 600 MHz, 8 MB flash, 1 MB on-chip RAM) with Zephyr v4.4.2 and GCC 14.3 at -Os. The builds were not flashed or run.

Reference app, flash

104.9 KB

1.3% of 8 MB

Reference app, static RAM

28.7 KB

11.2% of the 256 KB default RAM region (1 MB on chip)

Builds measured

305

0 failed or inexact

Services catalogued

279

263 built · 16 not available

Key findings

Flash is not the limit; RAM is. A full managed device (DHCP, DNS, SNTP, mDNS, MQTT over TLS, HTTP REST and SNMP) uses 293 KB, which is 3.6% of the 8 MB flash. It uses 126 KB static RAM, which is half of the 256 KB region that the board's default linker script uses (OCRAM). The other 768 KB of on-chip RAM (DTCM, ITCM, OCRAM2) stay empty unless the application places data there.
The reference app is mostly infrastructure. Of its 105 KB, the shell and its commands are 34 KB, the USB device stack is 28 KB and logging is 16 KB. The application modules are each 0.1 KB to 1.2 KB. The minimal shell saves 16.5 KB with no other change.
Networking costs RAM before it does anything. Ethernet, IPv4 and UDP add 26 KB flash and 32 KB RAM: the ENET DMA buffers and the default packet pools. Smaller pools save 7 KB RAM. BSD sockets add 12 KB flash and TCP adds a further 12 KB.
Protocols are cheap; security is not. MQTT is 4 KB, SNMP 17 KB, CoAP 8–11 KB and the HTTP server 28 KB. TLS (mbedTLS) is 72 KB flash and 40 KB RAM, which is more than the whole TCP/IP stack. For ECDSA P-256, the p256-m implementation is 6.5 KB against 18.5 KB for the mbedTLS ECP code.
Diagnostics can be larger than the feature. The network shell is 41 KB, ten times the MQTT client. The sensor shell is 20 KB, against 1.5 KB for the BME280 driver. Assertions add 26 KB to the reference app.
Shared code is visible in combinations. For the full device, the measured cost is 188 KB flash, against 209 KB for the sum of the separate catalogue deltas. TLS, the HTTP server and MQTT share mbedTLS, sockets and the heap.
Ethernet over USB is a real option. USB CDC-NCM with the Ethernet MAC off costs 5 KB less flash and 6.3 KB less RAM than the Ethernet driver. The SNMP setup over USB (NCM, TCP/IP, SNMP agent with traps and a private MIB) totals 168 KB flash and 64 KB RAM.
The FPU is off by default on this board. Turning on the Cortex-M7 double-precision FPU costs 0.5 KB flash and 1.3 KB RAM. The float printf support that comes with it by default costs another 4.7 KB.
Field buses are small. FlexCAN is 8.4 KB, CANopenNode 17 KB on top of it, Modbus RTU 5–6 KB and LoRaWAN 30 KB on top of the SX1276 driver.
The largest single items are UI, audio and DSP libraries. LVGL is 212 KB, the LC3 codec 103 KB and CMSIS-DSP 82 KB. C++ exceptions add 35 KB, but the full C++ standard library alone adds only 2.8 KB, because the linker keeps only what the code uses.
Isolation has a fixed entry price. Turning on userspace (MPU-isolated user threads) costs 49 KB flash and 7.4 KB RAM before any user thread exists; each user thread in its own memory domain then adds only 0.6 KB flash and 2 KB RAM. For structured messages, nanopb (Protocol Buffers) costs 6.2 KB and no static RAM; Thrift costs 74 KB because it needs the full C++ library with exceptions.

The reference app

Every measurement starts from the same small, typical Zephyr application, the reference app. It has a console and command shell over USB (CDC-ACM), logging, a GPIO shell, C++20 and a few small application modules (shell commands, LED control, one worker thread). Catalogue costs are measured on top of it. The first chart shows where its bytes go, from the linker map. The second removes one module at a time.

Where the bytes go

“(merged strings)” is all string literals: the linker merges them into one pool. “(linker fill)” is alignment padding, mostly the 8 KB FlexSPI boot header area.

Cost of each module (leave one out)

Bar = app size minus the size without that module. Where other modules depend on it, they are removed too.

Table: module cost and the components that go with it

Module	FLASH cost	RAM cost	Notes	Main components removed	Status
Shell subsystem (with all commands) `abl.shell`	34.2 KB	6.1 KB	Removes the shell and every command that needs it, including all app shell sources. Only main.cpp stays.	`subsys/shell` -16.3 KB / RAM -4.3 KB `(merged strings)` -6.9 KB `drivers/gpio` -2.7 KB / RAM -0.0 KB `kernel` -1.7 KB / RAM -0.2 KB `toolchain libs (libc, libgcc)` -1.5 KB	ok
USB device stack + CDC-ACM `abl.usb`	28.1 KB	16.5 KB	Console and shell move to the board default LPUART6 (pins 0/1). Measures USB stack cost against a plain UART.	`subsys/usb` -13.0 KB / RAM -5.6 KB `drivers/usb` -4.9 KB / RAM -3.4 KB `modules/hal_nxp` -3.4 KB / RAM -3.2 KB `kernel` -3.2 KB / RAM -1.3 KB `(merged strings)` -2.4 KB	ok
Logging subsystem `abl.log`	16.1 KB	2.9 KB	LOG_* macros compile to nothing; printk stays.	`subsys/logging` -3.9 KB / RAM -2.2 KB `(merged strings)` -3.7 KB `lib/os` -3.1 KB / RAM -0.0 KB `subsys/usb` -2.0 KB / RAM -0.0 KB `subsys/shell` -1.2 KB / RAM -0.6 KB	ok
GPIO shell (gpio info/toggle/blink) `abl.gpio_shell`	3.9 KB	0.1 KB		`drivers/gpio` -2.5 KB / RAM -0.0 KB `(merged strings)` -1.1 KB `kernel` -0.2 KB `toolchain libs (libc, libgcc)` -0.1 KB `subsys/shell` -0.0 KB	ok
kernel shell commands `abl.kernel_shell`	3.8 KB	0.4 KB		`subsys/shell` -1.5 KB / RAM -0.0 KB `(merged strings)` -1.4 KB `kernel` -0.8 KB / RAM -0.2 KB `subsys/logging` -0.1 KB / RAM -0.0 KB `arch (Cortex-M7)` -0.0 KB	ok
devmem shell command `abl.devmem_shell`	2.8 KB	0.1 KB		`subsys/shell` -1.4 KB / RAM -0.0 KB `(merged strings)` -0.7 KB `lib/utils` -0.4 KB / RAM -0.0 KB `toolchain libs (libc, libgcc)` -0.3 KB `lib/posix` -0.0 KB / RAM -0.0 KB	ok
date shell command `abl.date_shell`	2.1 KB	0.0 KB		`subsys/shell` -0.6 KB `toolchain libs (libc, libgcc)` -0.6 KB `lib/utils` -0.4 KB `lib/os` -0.4 KB / RAM -0.0 KB `(merged strings)` -0.2 KB	ok
threaded LED blink (thread + stack) `abl.src.led_ctrl_threaded`	1.2 KB	1.2 KB		`app (application code)` -0.6 KB / RAM -1.3 KB `(merged strings)` -0.5 KB `kernel` -0.1 KB	ok
device shell commands `abl.device_shell`	1.1 KB	0.0 KB		`subsys/shell` -0.8 KB `(merged strings)` -0.3 KB `kernel` -0.0 KB `(linker fill)` +0.0 KB	ok
GPIO get-direction/get-config API `abl.gpio_get_dir_cfg`	0.7 KB	0.0 KB	GPIO_SHELL info needs these, so GPIO_SHELL_INFO_CMD is also removed.	`drivers/gpio` -0.5 KB `(merged strings)` -0.2 KB `(linker fill)` -0.0 KB	ok
boot-probe shell commands `abl.src.boot_probe_cmd`	0.4 KB	0.0 KB		`app (application code)` -0.2 KB `(merged strings)` -0.2 KB `(linker fill)` +0.0 KB	ok
UART line control API `abl.uart_line_ctrl`	0.4 KB	0.0 KB		`subsys/usb` -0.3 KB `drivers/serial` -0.1 KB	ok
simpleecho shell commands `abl.src.simpleecho`	0.3 KB	0.0 KB		`(merged strings)` -0.2 KB `app (application code)` -0.1 KB `(linker fill)` -0.0 KB	ok
Boot-probe module (init-level counters, Kconfig off) `abl.mod.grey_boot_probe`	0.3 KB	0.0 KB	CONFIG_GREY_BOOT_PROBE=n; the shell command stays and reports "disabled".	`app (application code)` -0.2 KB / RAM -0.0 KB `(merged strings)` -0.0 KB	ok
Console (printk output to UART) `abl.console`	0.2 KB	0.0 KB		`drivers/console` -0.1 KB `lib/libc` -0.1 KB / RAM -0.0 KB `lib/os` -0.0 KB / RAM -0.0 KB `(linker fill)` -0.0 KB	ok
basic LED toggle command `abl.src.led_ctrl_basic`	0.2 KB	0.0 KB		`app (application code)` -0.1 KB `(merged strings)` -0.1 KB `(linker fill)` +0.0 KB	ok
bootloader shell command `abl.src.bootloader`	0.1 KB	0.0 KB		`app (application code)` -0.1 KB `(merged strings)` -0.0 KB `(linker fill)` +0.0 KB	ok

Tuning knobs

Each knob applied alone to the reference app. saves bytes costs bytes.

Table: Kconfig lines and notes

Knob	FLASH change	RAM change	Notes	Status
Minimal shell (no history, tab, VT100, help) `CONFIG_SHELL_MINIMAL=y`	-16.5 KB	-0.9 KB		ok
Minimal log mode `CONFIG_LOG_MODE_MINIMAL=y`	-9.2 KB	-2.9 KB		ok
Link-time optimisation `CONFIG_LTO=y CONFIG_ISR_TABLES_LOCAL_DECLARATION=y`	-7.6 KB	-4.1 KB		ok
Thread monitor and names off `CONFIG_KERNEL_SHELL=n CONFIG_THREAD_MONITOR=n CONFIG_THREAD_NAME=n`	-3.8 KB	-0.4 KB	KERNEL_SHELL uses them; the kernel shell is also removed. THREAD_STACK_INFO stays (MPU stack guard needs it).	ok
Boot banner off `CONFIG_BOOT_BANNER=n`	-1.2 KB	+0.0 KB		ok
Shell log backend off `CONFIG_SHELL_LOG_BACKEND=n`	-1.0 KB	-0.6 KB		ok
Shell history off `CONFIG_SHELL_HISTORY=n`	-0.9 KB	-0.6 KB		ok
cbprintf nano formatter `CONFIG_CBPRINTF_NANO=y`	-0.7 KB	+0.0 KB		ok
Time slicing off `CONFIG_TIMESLICING=n`	-0.5 KB	-0.1 KB		ok
Exception debug (fault dump) off `CONFIG_EXCEPTION_DEBUG=n`	-0.3 KB	+0.0 KB		ok
Hardware FPU on, float printf off `CONFIG_FPU=y CONFIG_CBPRINTF_FP_SUPPORT=n CONFIG_PICOLIBC_IO_LONG_LONG=y`	+0.5 KB	+1.2 KB	FPU and FPU_SHARING on, but keep the integer-only printf of the app.	ok
Minimal libc instead of picolibc `CONFIG_MINIMAL_LIBC=y`	+0.6 KB	-0.1 KB		ok
Hardware FPU on (hard-float ABI) `CONFIG_FPU=y`	+5.1 KB	+1.2 KB	The board default leaves the Cortex-M7 double-precision FPU off; float code then uses libgcc soft-float. FPU=y also turns on FPU_SHARING, float printf in picolibc and cbprintf, which is most of the cost.	ok
Default log level DEBUG `CONFIG_LOG_DEFAULT_LEVEL=4`	+8.7 KB	+0.0 KB		ok
-O2 speed optimisation (instead of -Os) `CONFIG_SPEED_OPTIMIZATIONS=y`	+19.3 KB	+0.0 KB		ok
-Og debug optimisation (instead of -Os) `CONFIG_DEBUG_OPTIMIZATIONS=y`	+25.3 KB	+0.1 KB		ok
Assertions on `CONFIG_ASSERT=y`	+25.7 KB	+1.3 KB		ok

Service catalogue

Each service is measured against its parent build: a network service against the TCP/IP base, ISO-TP against the CAN driver, and so on. Point at a bar to see its parent and the components it adds. Library services include a small, never-run caller so that the linker keeps their code.

NetworkingStorageSecurityOS services & debugLibraries, ML & UIDrivers & busesUSB classesIndustrial & field

The 40 largest services

Networking: 73 services

Storage: 15 services

Security: 25 services

OS services & debug: 53 services

Libraries, ML & UI: 20 services

Drivers & buses: 61 services

USB classes: 11 services

Industrial & field: 5 services

All services

Service	Domain / layer	FLASH Δ	RAM Δ	Total FLASH	Total RAM	RAM region use	Measured against	What it is · hardware · components	Status
TLS 1.2 sockets (mbedTLS + TLS credentials) `cat.net.tls`	Networking security	+71.7 KB	+40.5 KB	226.5 KB	107.8 KB	42%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	mbedTLS 4 + TF-PSA-Crypto, TLS 1.2 with one ciphersuite (ECDHE-ECDSA-AES128-GCM-SHA256, X.509, PEM), a 30 KiB static mbedTLS heap and 2 KiB max record (as samples/net/mqtt_publisher overlay-tls), TLS socket option layer, credential store. components `modules/mbedtls` +60.8 KB / RAM +38.7 KB `subsys/net` +7.2 KB / RAM +1.7 KB `(merged strings)` +2.3 KB `lib/os` +0.8 KB / RAM +0.0 KB `lib/libc` +0.2 KB / RAM +0.0 KB	ok
LwM2M client (OMA, over CoAP/UDP) `cat.net.lwm2m`	Networking protocol	+52.6 KB	+24.5 KB	207.3 KB	91.9 KB	36%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Engine, RD client and the mandatory objects (security, server, device). No IPSO objects. components `subsys/net/lib/lwm2m` +38.0 KB / RAM +23.9 KB `(merged strings)` +5.8 KB `subsys/net/lib/coap` +3.3 KB / RAM +0.0 KB `toolchain libs (libc, libgcc)` +2.5 KB `subsys/net/lib/http` +1.1 KB	ok
net shell (net iface/ping/arp/conn/...) `cat.net.shell`	Networking debug	+41.4 KB	+0.5 KB	196.2 KB	67.9 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +22.0 KB / RAM +0.5 KB `(merged strings)` +14.2 KB `toolchain libs (libc, libgcc)` +4.8 KB `lib/utils` +0.2 KB `subsys/shell` +0.1 KB	ok
Ethernet + IPv6 + UDP (ND, MLD, ICMPv6; no IPv4) `cat.net.ipv6`	Networking connectivity	+40.3 KB	+34.5 KB	145.1 KB	63.2 KB	25%	`app` Reference app	IPv6-only root, compare with cat.net.ipv4 (both have parent app). components `subsys/net` +27.8 KB / RAM +17.6 KB `drivers/ethernet` +5.0 KB / RAM +15.9 KB `modules/hal_nxp` +4.2 KB / RAM +0.1 KB `subsys/net/l2/ethernet` +1.1 KB / RAM +0.0 KB `(merged strings)` +0.9 KB	ok
WireGuard VPN `cat.net.wireguard`	Networking security	+35.5 KB	+8.5 KB	190.2 KB	75.9 KB	30%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `modules/mbedtls` +19.9 KB / RAM +1.8 KB `subsys/net/lib/wireguard` +12.2 KB / RAM +4.5 KB `subsys/net` +1.5 KB / RAM +2.1 KB `subsys/net/l2/virtual` +0.9 KB / RAM +0.0 KB `lib/utils` +0.4 KB	ok
SNMP agent over USB CDC-NCM (ENET off, external zephyr-snmp) `cat.net.usb_ncm_snmp`	Networking protocol	+28.6 KB	+4.6 KB	154.5 KB	59.0 KB	23%	`cat.usb.cdc_ncm_only` USB CDC-NCM as the only network interface (ENET off)	External zephyr-snmp module (not in-tree) on the USB CDC-NCM network interface, with the Ethernet MAC off. Same conf and stub as cat.net.snmp. Delta = SNMP agent + BSD sockets + socket service on the NCM IPv4/UDP stack. Hardware: USB device port only; no Ethernet kit needed components `modules/snmp` +12.3 KB / RAM +1.7 KB `subsys/net` +11.6 KB / RAM +2.4 KB `lib/os` +2.6 KB / RAM +0.5 KB `kernel` +1.1 KB / RAM +0.0 KB `lib/utils` +0.8 KB	ok
HTTP server (HTTP/1.1 + HTTP/2, one static resource) `cat.net.http_server`	Networking protocol	+27.6 KB	+7.5 KB	182.4 KB	74.9 KB	29%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/http` +18.9 KB / RAM +7.2 KB `(merged strings)` +3.1 KB `lib/os` +2.1 KB / RAM +0.1 KB `subsys/net` +2.0 KB / RAM +0.1 KB `lib/utils` +0.8 KB	ok
Ethernet L2 + ENET driver + AF_PACKET sockets (no IP) `cat.net.eth_l2`	Networking connectivity	+27.5 KB	+32.9 KB	132.3 KB	61.6 KB	24%	`app` Reference app	Net core, net_pkt/net_buf pools, Ethernet L2, ENET MAC driver, MDIO, DP83825 PHY, BSD socket layer with AF_PACKET only. Zephyr needs at least one packet protocol, so raw packet sockets stand in for IP. Not a parent of the IP chain. components `subsys/net` +14.1 KB / RAM +15.8 KB `drivers/ethernet` +5.0 KB / RAM +15.9 KB `modules/hal_nxp` +4.2 KB / RAM +0.1 KB `kernel` +1.4 KB / RAM +0.6 KB `(merged strings)` +0.9 KB	ok
HTTPS server (HTTP server on TLS sockets) `cat.net.https_server`	Networking protocol	+26.0 KB	+7.5 KB	252.5 KB	115.3 KB	45%	`cat.net.tls` TLS 1.2 sockets (mbedTLS + TLS credentials)	components `subsys/net/lib/http` +18.9 KB / RAM +7.2 KB `(merged strings)` +3.1 KB `lib/os` +1.3 KB / RAM +0.1 KB `subsys/net` +1.0 KB / RAM +0.1 KB `lib/utils` +0.8 KB	ok
Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP) `cat.net.ipv4`	Networking connectivity	+26.0 KB	+32.0 KB	130.8 KB	60.7 KB	24%	`app` Reference app	Minimal native IP stack on ENET; root of the IPv4 chain. Net core, Ethernet L2, ENET driver, PHY, IPv4, ARP, ICMPv4, UDP, native net_context API. No BSD sockets. components `subsys/net` +10.9 KB / RAM +15.0 KB `drivers/ethernet` +5.0 KB / RAM +15.9 KB `modules/hal_nxp` +4.2 KB / RAM +0.1 KB `subsys/net/l2/ethernet` +3.7 KB / RAM +0.2 KB `(merged strings)` +0.9 KB	ok
IPv6 added to net base (dual-stack base) `cat.net.base6`	Networking protocol	+23.1 KB	+3.3 KB	177.9 KB	70.6 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Parent of IPv6-only services such as DHCPv6. components `subsys/net` +22.9 KB / RAM +3.3 KB `subsys/net/l2/ethernet` +0.1 KB `(merged strings)` +0.0 KB `lib/net_buf` +0.0 KB `drivers/ethernet` +0.0 KB / RAM +0.0 KB	ok
PTP (IEEE 1588) stack with ENET PTP clock `cat.net.ptp`	Networking protocol	+21.9 KB	+21.6 KB	176.7 KB	89.0 KB	35%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Enables the ENET 1588 timer node and the Zephyr PTP stack (UDP/IPv4 transport). components `subsys/net/lib/ptp` +10.6 KB / RAM +19.6 KB `subsys/net` +3.9 KB / RAM +1.8 KB `toolchain libs (libc, libgcc)` +2.2 KB `lib/os` +2.2 KB / RAM +0.1 KB `drivers/ptp_clock` +0.9 KB / RAM +0.0 KB	ok
IPv6 added to IPv4 (dual stack, UDP) `cat.net.dual`	Networking protocol	+20.7 KB	+3.1 KB	151.5 KB	63.8 KB	25%	`cat.net.ipv4` Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP)	components `subsys/net` +20.6 KB / RAM +3.1 KB `subsys/net/l2/ethernet` +0.1 KB `(merged strings)` +0.0 KB `lib/net_buf` +0.0 KB `drivers/ethernet` +0.0 KB / RAM +0.0 KB	ok
WebSocket client `cat.net.ws_client`	Networking protocol	+20.6 KB	+2.8 KB	175.3 KB	70.1 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	websocket_send_msg() uses k_malloc, so a 1500 B system heap is set (as samples/net/sockets/websocket_client). The handshake needs SHA-1, which pulls in mbedTLS/PSA crypto. components `subsys/net/lib/http` +8.7 KB `modules/mbedtls` +4.1 KB / RAM +0.8 KB `subsys/net/lib/websocket` +3.2 KB / RAM +0.1 KB `(merged strings)` +2.2 KB `lib/os` +0.8 KB	ok
gPTP (IEEE 802.1AS) with ENET PTP clock `cat.net.gptp`	Networking protocol	+20.3 KB	+6.0 KB	175.1 KB	73.4 KB	29%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Enables the ENET 1588 timer node (enet_ptp_clock) and the gPTP stack, grandmaster capable. components `subsys/net/l2/ethernet` +15.3 KB / RAM +4.1 KB `toolchain libs (libc, libgcc)` +2.4 KB `drivers/ptp_clock` +0.9 KB / RAM +0.0 KB `subsys/net` +0.7 KB / RAM +1.8 KB `modules/hal_nxp` +0.5 KB	ok
Wi-Fi via ESP-AT modem (ESP32/ESP8266 on LPUART2) `cat.net.esp_at`	Networking connectivity	+17.3 KB	+13.1 KB	172.0 KB	80.5 KB	31%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Offloaded Wi-Fi driver (AT commands) plus Wi-Fi management L2, next to Ethernet. Hardware: ESP32 or ESP8266 with ESP-AT firmware on LPUART2 (pins 7/8) components `drivers/wifi` +9.4 KB / RAM +10.9 KB `subsys/net` +3.4 KB / RAM +2.1 KB `drivers/modem` +2.3 KB / RAM +0.0 KB `(merged strings)` +1.9 KB `drivers/serial` +0.2 KB / RAM +0.0 KB	ok
SNMP v1/v2c agent (external zephyr-snmp module) `cat.net.snmp`	Networking protocol	+17.0 KB	+3.4 KB	159.4 KB	65.3 KB	26%	`cat.net.ipv4_sockets` BSD sockets on IPv4/UDP	External out-of-tree module simpleiot/zephyr-snmp v0.1.0 (BSD-3, lwIP-derived), not in Zephyr. Agent on UDP 161 via the socket service, with the default MIB-2 system, interfaces and snmp groups, and one install_snmp_handler() callback on a private OID. Parent is the UDP-only socket stack (no TCP); the delta includes the socket service. components `modules/snmp` +12.3 KB / RAM +1.7 KB `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net` +1.3 KB / RAM +1.5 KB `lib/utils` +0.8 KB `kernel` +0.2 KB	ok
OCPP 1.6 charge point (on WebSocket client + JSON) `cat.net.ocpp`	Networking industrial	+16.6 KB	+9.3 KB	191.9 KB	79.5 KB	31%	`cat.net.ws_client` WebSocket client	components `subsys/net/lib/ocpp` +8.6 KB / RAM +9.4 KB `lib/utils` +4.9 KB `(merged strings)` +1.9 KB `subsys/net` +0.5 KB `toolchain libs (libc, libgcc)` +0.4 KB	ok
Cellular modem (modem_cellular, Quectel BG9x on LPUART2) `cat.net.cellular`	Networking connectivity	+13.5 KB	+4.0 KB	168.2 KB	71.4 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Generic modem subsystem (chat, CMUX, modem PPP, UART backend) and the cellular driver. Hardware: Quectel BG95/BG96 modem on LPUART2 (pins 7/8) with a power-key GPIO components `subsys/net/l2/ppp` +6.7 KB / RAM +1.3 KB `subsys/net` +4.2 KB / RAM +2.6 KB `drivers/modem` +0.8 KB / RAM +0.0 KB `kernel` +0.5 KB `(merged strings)` +0.4 KB	ok
DNS resolver + getaddrinfo() `cat.net.dns`	Networking protocol	+12.6 KB	+5.3 KB	167.4 KB	72.7 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/dns` +5.2 KB / RAM +3.1 KB `subsys/net` +3.7 KB / RAM +1.7 KB `lib/os` +2.2 KB / RAM +0.1 KB `lib/utils` +0.8 KB `kernel` +0.3 KB / RAM +0.3 KB	ok
WebSocket server (on HTTP server) `cat.net.ws_server`	Networking protocol	+12.4 KB	+2.8 KB	194.8 KB	77.6 KB	30%	`cat.net.http_server` HTTP server (HTTP/1.1 + HTTP/2, one static resource)	Selects the WebSocket library (SHA-1 via mbedTLS/PSA). websocket_send_msg() uses k_malloc, so a 1500 B system heap is set. components `modules/mbedtls` +8.3 KB / RAM +0.8 KB `subsys/net/lib/websocket` +2.5 KB / RAM +0.1 KB `subsys/net/lib/http` +0.5 KB / RAM +0.1 KB `lib/utils` +0.3 KB `subsys/net` +0.2 KB / RAM +0.0 KB	ok
TCP (net base = IPv4 + UDP + TCP + sockets) `cat.net.base`	Networking protocol	+12.3 KB	+5.4 KB	154.8 KB	67.4 KB	26%	`cat.net.ipv4_sockets` BSD sockets on IPv4/UDP	TCP added under the socket layer, so the socket code reaches it and the linker keeps it (TCP without a user shows only about 3 KB). This is the parent of most services. components `subsys/net` +12.1 KB / RAM +5.4 KB `lib/net_buf` +0.1 KB `kernel` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
SocketCAN (AF_CAN raw sockets on FlexCAN1) `cat.net.socketcan`	Networking connectivity	+12.2 KB	+2.1 KB	167.0 KB	69.4 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Includes the FlexCAN driver (CAN is off in the app) and the CAN net interface. Hardware: CAN transceiver on FlexCAN1 (pins 22 TX / 23 RX) components `drivers/can` +4.8 KB / RAM +1.8 KB `modules/hal_nxp` +3.4 KB / RAM +0.0 KB `subsys/net` +2.5 KB / RAM +0.0 KB `(merged strings)` +0.8 KB `drivers/net` +0.5 KB / RAM +0.1 KB	ok
HTTP/1.1 client `cat.net.http_client`	Networking protocol	+12.1 KB	+0.2 KB	166.9 KB	67.6 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/http` +8.7 KB `(merged strings)` +2.0 KB `lib/os` +0.7 KB `subsys/net` +0.4 KB `toolchain libs (libc, libgcc)` +0.2 KB	ok
BSD sockets on IPv4/UDP `cat.net.ipv4_sockets`	Networking protocol	+11.6 KB	+1.2 KB	142.4 KB	61.9 KB	24%	`cat.net.ipv4` Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP)	BSD socket API with ZVFS file descriptors, poll and select, UDP only. components `subsys/net` +10.3 KB / RAM +0.9 KB `kernel` +0.9 KB / RAM +0.0 KB `lib/os` +0.3 KB / RAM +0.3 KB `(linker fill)` -0.0 KB	ok
CoAP server (coap_service) `cat.net.coap_server`	Networking protocol	+11.0 KB	+9.2 KB	165.8 KB	76.6 KB	30%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/coap` +5.4 KB / RAM +7.1 KB `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net` +1.6 KB / RAM +1.5 KB `lib/utils` +0.8 KB `app (application code)` +0.7 KB / RAM +0.6 KB	ok
HTTPS client (HTTP client on TLS sockets) `cat.net.https_client`	Networking protocol	+11.0 KB	+0.2 KB	237.5 KB	108.1 KB	42%	`cat.net.tls` TLS 1.2 sockets (mbedTLS + TLS credentials)	components `subsys/net/lib/http` +8.7 KB `(merged strings)` +2.0 KB `toolchain libs (libc, libgcc)` +0.2 KB `app (application code)` +0.1 KB / RAM +0.2 KB	ok
PPP over UART (LPUART2, pins 7/8) `cat.net.ppp`	Networking connectivity	+10.7 KB	+4.8 KB	165.5 KB	72.2 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	PPP L2 and the UART PPP driver as a second interface next to Ethernet. Hardware: Serial PPP peer on LPUART2 (Teensy pins 7 RX2 / 8 TX2) components `subsys/net/l2/ppp` +6.3 KB / RAM +1.3 KB `drivers/net` +2.0 KB / RAM +2.0 KB `subsys/net` +1.9 KB / RAM +1.5 KB `(merged strings)` +0.3 KB `drivers/serial` +0.2 KB / RAM +0.0 KB	ok
mDNS responder `cat.net.mdns`	Networking protocol	+10.7 KB	+5.6 KB	165.5 KB	73.0 KB	29%	`cat.net.hostname` Hostname	components `subsys/net` +5.1 KB / RAM +3.0 KB `subsys/net/lib/dns` +2.2 KB / RAM +2.4 KB `lib/os` +2.2 KB / RAM +0.1 KB `lib/utils` +0.8 KB `kernel` +0.2 KB	ok
MQTT-SN client over UDP `cat.net.mqtt_sn`	Networking protocol	+10.3 KB	+5.3 KB	165.0 KB	72.6 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/mqtt_sn` +6.2 KB / RAM +4.8 KB `subsys/net` +3.0 KB / RAM +0.0 KB `lib/os` +0.7 KB `app (application code)` +0.2 KB / RAM +0.4 KB `lib/net_buf` +0.1 KB	ok
DHCPv4 server `cat.net.dhcpv4_server`	Networking protocol	+10.1 KB	+3.3 KB	164.8 KB	70.7 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/dhcpv4` +4.7 KB / RAM +0.5 KB `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net` +2.0 KB / RAM +2.7 KB `lib/utils` +0.8 KB `kernel` +0.3 KB	ok
LLMNR responder `cat.net.llmnr`	Networking protocol	+9.5 KB	+4.1 KB	164.4 KB	71.5 KB	28%	`cat.net.hostname` Hostname	components `subsys/net` +5.0 KB / RAM +2.8 KB `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net/lib/dns` +1.3 KB / RAM +1.2 KB `lib/utils` +0.8 KB `kernel` +0.2 KB	ok
zperf throughput tool (UDP + TCP, client + server) `cat.net.zperf`	Networking debug	+9.5 KB	+10.9 KB	164.2 KB	78.3 KB	31%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/zperf` +4.3 KB / RAM +9.2 KB `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net` +1.8 KB / RAM +1.6 KB `lib/utils` +0.8 KB `kernel` +0.2 KB	ok
DHCPv6 client `cat.net.dhcpv6`	Networking protocol	+9.4 KB	+1.6 KB	187.2 KB	72.2 KB	28%	`cat.net.base6` IPv6 added to net base (dual-stack base)	components `subsys/net/lib/dhcpv6` +5.7 KB / RAM +0.1 KB `toolchain libs (libc, libgcc)` +2.0 KB `subsys/net` +1.5 KB / RAM +1.3 KB `drivers/ethernet` +0.2 KB / RAM +0.2 KB `app (application code)` +0.1 KB	ok
DTLS 1.2 sockets (on TLS) `cat.net.dtls`	Networking security	+9.1 KB	+0.1 KB	235.6 KB	108.0 KB	42%	`cat.net.tls` TLS 1.2 sockets (mbedTLS + TLS credentials)	components `modules/mbedtls` +6.1 KB `subsys/net` +2.9 KB / RAM +0.2 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
Shell telnet backend (TCP 23) `cat.net.telnet`	Networking debug	+8.0 KB	+6.3 KB	162.8 KB	73.7 KB	29%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/shell` +2.6 KB / RAM +4.7 KB `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net` +1.4 KB / RAM +1.5 KB `lib/utils` +0.8 KB `(merged strings)` +0.7 KB	ok
CoAP client `cat.net.coap_client`	Networking protocol	+7.8 KB	+2.8 KB	162.5 KB	70.2 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/coap` +6.6 KB / RAM +1.3 KB `lib/os` +0.7 KB `subsys/net` +0.3 KB `app (application code)` +0.1 KB / RAM +1.5 KB `(merged strings)` +0.1 KB	ok
Packet capture (IPIP tunnel to a host) `cat.net.capture`	Networking debug	+7.4 KB	+4.8 KB	162.2 KB	72.1 KB	28%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Copies packets into an IPv4-in-IPv4 tunnel to a host that runs Wireshark. components `subsys/net` +4.6 KB / RAM +4.5 KB `subsys/net/l2/virtual` +2.4 KB / RAM +0.2 KB `toolchain libs (libc, libgcc)` +0.2 KB `(merged strings)` +0.1 KB `app (application code)` +0.1 KB	ok
Modbus TCP server (raw ADU over a TCP socket) `cat.net.modbus_tcp`	Networking industrial	+5.4 KB	+0.7 KB	160.2 KB	68.0 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/modbus` +3.7 KB / RAM +0.6 KB `(merged strings)` +0.9 KB `subsys/net` +0.4 KB `app (application code)` +0.3 KB / RAM +0.1 KB `lib/os` +0.1 KB	ok
REST/JSON endpoint (JSON library) `cat.net.http_rest`	Networking protocol	+4.8 KB	+0.1 KB	187.3 KB	75.0 KB	29%	`cat.net.http_dynamic` HTTP server dynamic resource (callback)	components `lib/utils` +4.2 KB `toolchain libs (libc, libgcc)` +0.3 KB `app (application code)` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
DHCPv4 client `cat.net.dhcpv4`	Networking protocol	+4.6 KB	+1.5 KB	159.3 KB	68.8 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/dhcpv4` +3.0 KB / RAM +0.1 KB `subsys/net` +1.4 KB / RAM +1.3 KB `drivers/ethernet` +0.1 KB / RAM +0.1 KB `app (application code)` +0.0 KB `(merged strings)` +0.0 KB	ok
Socket service (shared poll thread) `cat.net.socket_service`	Networking os-service	+4.3 KB	+1.6 KB	159.1 KB	69.0 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `lib/os` +2.2 KB / RAM +0.1 KB `subsys/net` +1.0 KB / RAM +1.5 KB `lib/utils` +0.8 KB `kernel` +0.2 KB `app (application code)` +0.1 KB / RAM +0.0 KB	ok
MQTT 3.1.1 client `cat.net.mqtt`	Networking protocol	+4.1 KB	+0.4 KB	158.9 KB	67.7 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/mqtt` +3.1 KB `subsys/net` +0.6 KB `lib/os` +0.2 KB `app (application code)` +0.2 KB / RAM +0.4 KB `(merged strings)` +0.0 KB	ok
FTP client `cat.net.ftp`	Networking protocol	+4.0 KB	+4.4 KB	171.4 KB	77.1 KB	30%	`cat.net.dns` DNS resolver + getaddrinfo()	ftp_open() resolves the host name with getaddrinfo(), which needs k_calloc; the DNS resolver variant provides the heap. components `subsys/net/lib/ftp` +2.4 KB / RAM +2.3 KB `(merged strings)` +0.8 KB `subsys/net` +0.5 KB `kernel` +0.1 KB `app (application code)` +0.1 KB / RAM +2.1 KB	ok
MQTT over TLS (on TLS sockets) `cat.net.mqtt_tls`	Networking protocol	+4.0 KB	+0.4 KB	230.5 KB	108.2 KB	42%	`cat.net.tls` TLS 1.2 sockets (mbedTLS + TLS credentials)	components `subsys/net/lib/mqtt` +3.7 KB `app (application code)` +0.2 KB / RAM +0.4 KB `subsys/net` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
IPv4 link-local autoconf (169.254/16) + ACD `cat.net.ipv4_autoconf`	Networking protocol	+4.0 KB	+1.8 KB	158.8 KB	69.1 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +3.8 KB / RAM +1.8 KB `subsys/net/l2/ethernet` +0.2 KB `drivers/ethernet` +0.0 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
MQTT 5.0 client (instead of 3.1.1) `cat.net.mqtt5`	Networking protocol	+3.6 KB	+0.4 KB	162.4 KB	68.2 KB	27%	`cat.net.mqtt` MQTT 3.1.1 client	Same stub with MQTT_VERSION_5_0; delta = extra cost of MQTT 5 properties and AUTH over 3.1.1. components `subsys/net/lib/mqtt` +3.5 KB `app (application code)` +0.0 KB / RAM +0.4 KB `(linker fill)` +0.0 KB	ok
net_mgmt events + connection manager `cat.net.mgmt_events`	Networking os-service	+3.2 KB	+2.5 KB	158.0 KB	69.8 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	net_mgmt event bus and the L4 connection manager (connectivity up/down events). components `subsys/net` +3.2 KB / RAM +2.4 KB `(merged strings)` +0.0 KB	ok
DNS-SD service advertisement (on mDNS) `cat.net.dns_sd`	Networking protocol	+3.2 KB	+0.0 KB	168.6 KB	73.0 KB	29%	`cat.net.mdns` mDNS responder	components `subsys/net/lib/dns` +3.0 KB / RAM +0.0 KB `(merged strings)` +0.1 KB `subsys/net` +0.0 KB `app (application code)` +0.0 KB `(linker fill)` +0.0 KB	ok
IEEE 802.1Q VLAN (2 VLANs) `cat.net.vlan`	Networking protocol	+3.1 KB	+0.5 KB	157.9 KB	67.9 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/l2/ethernet` +1.9 KB / RAM +0.4 KB `subsys/net/l2/virtual` +0.9 KB / RAM +0.0 KB `subsys/net` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `app (application code)` +0.0 KB	ok
socketpair() (AF_UNIX stream pair) `cat.net.socketpair`	Networking os-service	+2.8 KB	+0.3 KB	157.6 KB	67.7 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +2.4 KB `kernel` +0.2 KB / RAM +0.4 KB `lib/os` +0.2 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
Net config library (static IPv4 at boot) `cat.net.config`	Networking os-service	+2.6 KB	+1.4 KB	157.4 KB	68.8 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.8 KB / RAM +1.3 KB `subsys/net/lib/config` +0.6 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `toolchain libs (libc, libgcc)` +0.0 KB	ok
IGMPv2/v3 multicast join `cat.net.igmp`	Networking protocol	+2.5 KB	+0.1 KB	157.3 KB	67.4 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +2.4 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Latency monitor (latmus client) `cat.net.latmon`	Networking debug	+2.4 KB	+8.3 KB	157.2 KB	75.7 KB	30%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.1 KB `lib/os` +0.7 KB `subsys/net/lib/latmon` +0.5 KB / RAM +8.3 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
Syslog log backend over UDP `cat.net.syslog`	Networking debug	+2.4 KB	+0.9 KB	157.2 KB	68.2 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.1 KB `subsys/logging` +0.8 KB / RAM +0.9 KB `lib/os` +0.2 KB `toolchain libs (libc, libgcc)` +0.2 KB `(merged strings)` +0.2 KB	ok
Promiscuous mode API `cat.net.promisc`	Networking protocol	+2.2 KB	+1.3 KB	156.9 KB	68.7 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.3 KB / RAM +1.3 KB `subsys/net/l2/ethernet` +0.8 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `drivers/ethernet` +0.0 KB	ok
LLDP (IEEE 802.1AB) transmit `cat.net.lldp`	Networking protocol	+1.9 KB	+1.4 KB	156.7 KB	68.8 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.0 KB / RAM +1.3 KB `subsys/net/l2/ethernet` +0.9 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB `drivers/ethernet` +0.0 KB / RAM +0.0 KB	ok
Network statistics + user API `cat.net.stats`	Networking debug	+1.9 KB	+0.4 KB	156.7 KB	67.7 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.3 KB / RAM +0.2 KB `subsys/net/l2/ethernet` +0.3 KB `drivers/ethernet` +0.2 KB / RAM +0.2 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
TFTP client `cat.net.tftp`	Networking protocol	+1.8 KB	+0.5 KB	156.6 KB	67.9 KB	27%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `lib/os` +0.7 KB `subsys/net/lib/tftp` +0.6 KB `subsys/net` +0.4 KB `app (application code)` +0.1 KB / RAM +0.5 KB `(merged strings)` +0.0 KB	ok
IPv6 fragmentation and reassembly `cat.net.ipv6_frag`	Networking protocol	+1.7 KB	+0.4 KB	179.6 KB	71.1 KB	28%	`cat.net.base6` IPv6 added to net base (dual-stack base)	components `subsys/net` +1.7 KB / RAM +0.5 KB	ok
IPv4 fragmentation and reassembly `cat.net.ipv4_frag`	Networking protocol	+1.4 KB	+0.2 KB	156.2 KB	67.6 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +1.4 KB / RAM +0.2 KB `(linker fill)` +0.0 KB	ok
Prometheus metrics endpoint (on HTTP server) `cat.net.prometheus`	Networking protocol	+1.3 KB	+0.4 KB	183.7 KB	75.3 KB	29%	`cat.net.http_server` HTTP server (HTTP/1.1 + HTTP/2, one static resource)	components `subsys/net` +0.8 KB `(merged strings)` +0.3 KB `app (application code)` +0.2 KB / RAM +0.4 KB `toolchain libs (libc, libgcc)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
SNTP client (on DNS resolver) `cat.net.sntp`	Networking protocol	+1.2 KB	+0.1 KB	168.6 KB	72.8 KB	28%	`cat.net.dns` DNS resolver + getaddrinfo()	sntp_simple() resolves the server name with getaddrinfo(), which needs k_calloc; the DNS resolver variant provides the heap. components `subsys/net/lib/sntp` +0.9 KB / RAM +0.1 KB `subsys/net/lib/utils` +0.1 KB `subsys/net` +0.1 KB `app (application code)` +0.0 KB `(merged strings)` +0.0 KB	ok
SOCKS5 proxy client `cat.net.socks`	Networking protocol	+1.1 KB	+0.1 KB	155.8 KB	67.4 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net/lib/socks` +0.4 KB `subsys/net` +0.4 KB / RAM +0.1 KB `lib/os` +0.1 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
SNMP trap sending (external zephyr-snmp) `cat.net.snmp_traps`	Networking protocol	+0.7 KB	+0.0 KB	160.1 KB	65.3 KB	26%	`cat.net.snmp` SNMP v1/v2c agent (external zephyr-snmp module)	Adds a trap destination and snmp_send_trap_generic() to the external zephyr-snmp agent. components `subsys/net` +0.4 KB `modules/snmp` +0.1 KB `app (application code)` +0.0 KB `toolchain libs (libc, libgcc)` +0.0 KB `(merged strings)` +0.0 KB	ok
ICMP echo request API (ping) `cat.net.ping`	Networking protocol	+0.6 KB	+0.1 KB	155.3 KB	67.4 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	ICMPv4 echo reply is always in the stack; this adds the net_icmp echo-request API used by ping. components `subsys/net` +0.5 KB / RAM +0.0 KB `app (application code)` +0.1 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
Packet filter (npf) `cat.net.pkt_filter`	Networking security	+0.4 KB	+0.1 KB	155.2 KB	67.4 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +0.3 KB / RAM +0.0 KB `app (application code)` +0.1 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
SNMP private MIB, 3 read-only scalars (external zephyr-snmp) `cat.net.snmp_private_mib`	Networking protocol	+0.3 KB	+0.0 KB	159.7 KB	65.3 KB	26%	`cat.net.snmp` SNMP v1/v2c agent (external zephyr-snmp module)	External zephyr-snmp module. Private MIB under 1.3.6.1.4.1.32473.1 with 3 SNMP_SCALAR_CREATE_NODE_READONLY scalars, registered with snmp_set_mibs() next to MIB-2. components `app (application code)` +0.3 KB / RAM +0.0 KB `modules/snmp` +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
HTTP server dynamic resource (callback) `cat.net.http_dynamic`	Networking protocol	+0.1 KB	+0.1 KB	182.5 KB	74.9 KB	29%	`cat.net.http_server` HTTP server (HTTP/1.1 + HTTP/2, one static resource)	components `app (application code)` +0.1 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
Hostname `cat.net.hostname`	Networking os-service	+0.0 KB	+0.0 KB	154.8 KB	67.4 KB	26%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	components `subsys/net` +0.0 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Smaller net_pkt/net_buf pools (tuning) `cat.net.small_pools`	Networking os-service	+0.0 KB	-6.8 KB	154.8 KB	60.5 KB	24%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	8+8 packets and 16+16 buffers instead of the defaults 14+14 and 36+36 (128 B each). Negative RAM delta = what the default pools cost above this size. components `subsys/net` +0.0 KB / RAM -6.8 KB	ok
SNMP agent without MIB-2 interfaces group (negative delta) `cat.net.snmp_no_mib2_if`	Networking protocol	-1.4 KB	+0.0 KB	158.0 KB	65.3 KB	26%	`cat.net.snmp` SNMP v1/v2c agent (external zephyr-snmp module)	External zephyr-snmp agent with SNMP_AGENT_MIB2_INTERFACES=n; the delta is minus the cost of the ifTable group. components `modules/snmp` -1.3 KB `subsys/net` -0.1 KB `(merged strings)` -0.0 KB `(linker fill)` -0.0 KB	ok
ARP off (negative delta = ARP cost) `cat.net.arp_off`	Networking protocol	-2.7 KB	-0.2 KB	128.1 KB	60.5 KB	24%	`cat.net.ipv4` Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP)	IPv4 without ARP. Not usable on Ethernet; the delta is minus the ARP cost. components `subsys/net/l2/ethernet` -2.5 KB / RAM -0.2 KB `kernel` -0.1 KB `subsys/net` -0.1 KB `(merged strings)` -0.0 KB `(linker fill)` +0.0 KB	ok
MQTT over WebSocket (on WebSocket client) `cat.net.mqtt_ws`	Networking protocol	–	–	–	–	–	`cat.net.ws_client` WebSocket client		not available: Does not compile in Zephyr v4.4.2. subsys/net/lib/mqtt/mqtt_transport_websocket.c uses NET_ERR/NET_DBG/NET_INFO but does not include zephyr/net/net_log.h (implicit declaration errors). Fix upstream with one include line; then remove this na.
OpenThread (Thread mesh) `cat.net.openthread`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: Needs an IEEE 802.15.4 radio; Teensy 4.1 has none (an RCP over UART/SPI would be external hardware).
IEEE 802.15.4 L2 / 6LoWPAN `cat.net.ieee802154`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: No 802.15.4 radio on Teensy 4.1.
Bluetooth LE (and IPSP / BLE networking) `cat.net.bt_ipsp`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: No Bluetooth controller on Teensy 4.1 (an external HCI controller over UART would be needed).
Native Wi-Fi (wpa_supplicant, hostap) `cat.net.wifi_native`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: No on-chip Wi-Fi. Only an offloaded AT modem (cat.net.esp_at) applies.
Ethernet bridge `cat.net.bridge`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: Teensy 4.1 has one Ethernet port; a bridge needs two or more.
DSA (distributed switch architecture) `cat.net.dsa`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: No Ethernet switch chip on Teensy 4.1.
10BASE-T1S `cat.net.t1s`	Networking connectivity	–	–	–	–	–	`app` Reference app		not available: Needs a T1S MAC-PHY (for example LAN865x on SPI); the board has a DP83825 100BASE-TX PHY.
LittleFS on flash (VFS + littlefs) `cat.store.littlefs`	Storage storage	+21.5 KB	+1.6 KB	135.9 KB	39.3 KB	15%	`cat.store.flash_map` Flash map + 1 MB storage partition	components `modules/littlefs` +14.9 KB `subsys/fs` +4.2 KB / RAM +1.1 KB `(merged strings)` +1.6 KB `app (application code)` +0.5 KB / RAM +0.5 KB `lib/libc` +0.1 KB / RAM +0.0 KB	ok
SD card disk access (uSDHC + SDMMC disk) `cat.store.sdmmc_disk`	Storage driver	+14.8 KB	+1.5 KB	119.7 KB	30.2 KB	12%	`app` Reference app	uSDHC1 host driver, SD stack and the zephyr,sdmmc-disk node "SD" from teensy41.dts. Hardware: microSD card in the on-board slot components `subsys/sd` +5.2 KB / RAM +0.0 KB `drivers/sdhc` +4.3 KB / RAM +0.4 KB `modules/hal_nxp` +2.6 KB / RAM +0.0 KB `(merged strings)` +1.7 KB `subsys/disk` +0.5 KB / RAM +0.0 KB	ok
ext2 on SD card `cat.store.ext2_sd`	Storage storage	+14.2 KB	+43.8 KB	133.9 KB	74.0 KB	29%	`cat.store.sdmmc_disk` SD card disk access (uSDHC + SDMMC disk)	Hardware: microSD card in the on-board slot components `subsys/fs` +11.5 KB / RAM +43.8 KB `(merged strings)` +2.5 KB `app (application code)` +0.2 KB / RAM +0.0 KB `kernel` +0.0 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
FAT FS (ELM FatFs) on SD card `cat.store.fatfs_sd`	Storage storage	+11.5 KB	+1.0 KB	131.2 KB	31.2 KB	12%	`cat.store.sdmmc_disk` SD card disk access (uSDHC + SDMMC disk)	Hardware: microSD card in the on-board slot components `modules/fatfs` +7.9 KB / RAM +0.0 KB `subsys/fs` +2.6 KB / RAM +0.4 KB `(merged strings)` +0.8 KB `app (application code)` +0.2 KB / RAM +0.6 KB `subsys/disk` +0.0 KB	ok
Flash driver (FlexSPI NOR, read/erase/write) `cat.store.flash`	Storage driver	+9.2 KB	+9.0 KB	114.0 KB	37.7 KB	15%	`app` Reference app	MCUX FlexSPI NOR driver on the 8 MB W25Q64 that also holds the XIP code. components `drivers/flash` +4.9 KB / RAM +5.1 KB `modules/hal_nxp` +2.7 KB / RAM +2.7 KB `drivers/memc` +1.1 KB / RAM +1.0 KB `SoC (i.MX RT)` +0.1 KB / RAM +0.1 KB `app (application code)` +0.1 KB	ok
File system shell (fs ls/cat/write...) `cat.store.fs_shell`	Storage storage	+5.1 KB	+0.1 KB	141.0 KB	39.5 KB	15%	`cat.store.littlefs` LittleFS on flash (VFS + littlefs)	components `subsys/fs` +3.8 KB / RAM +0.1 KB `(merged strings)` +1.3 KB `toolchain libs (libc, libgcc)` +0.0 KB	ok
ZMS (Zephyr Memory Storage) `cat.store.zms`	Storage storage	+4.9 KB	+0.1 KB	119.3 KB	37.8 KB	15%	`cat.store.flash_map` Flash map + 1 MB storage partition	components `subsys/kvss` +4.1 KB / RAM +0.0 KB `(merged strings)` +0.6 KB `app (application code)` +0.1 KB / RAM +0.1 KB `drivers/flash` +0.1 KB `subsys/crc` +0.1 KB	ok
Flash shell commands `cat.store.flash_shell`	Storage storage	+4.4 KB	+8.2 KB	118.4 KB	46.0 KB	18%	`cat.store.flash` Flash driver (FlexSPI NOR, read/erase/write)	components `drivers/flash` +2.7 KB / RAM +8.3 KB `(merged strings)` +1.7 KB `subsys/shell` +0.0 KB `(linker fill)` +0.0 KB	ok
NVS key-value store `cat.store.nvs`	Storage storage	+4.0 KB	+0.1 KB	118.4 KB	37.8 KB	15%	`cat.store.flash_map` Flash map + 1 MB storage partition	components `subsys/kvss` +3.3 KB / RAM +0.0 KB `(merged strings)` +0.3 KB `drivers/flash` +0.1 KB `app (application code)` +0.1 KB / RAM +0.0 KB `subsys/crc` +0.1 KB	ok
Settings on ZMS `cat.store.settings_zms`	Storage storage	+2.9 KB	+0.2 KB	122.2 KB	38.0 KB	15%	`cat.store.zms` ZMS (Zephyr Memory Storage)	components `subsys/settings` +2.1 KB / RAM +0.1 KB `lib/hash` +0.2 KB `subsys/storage` +0.2 KB `(merged strings)` +0.1 KB `app (application code)` +0.1 KB / RAM +0.0 KB	ok
FCB (flash circular buffer) `cat.store.fcb`	Storage storage	+2.3 KB	+0.1 KB	116.7 KB	37.9 KB	15%	`cat.store.flash_map` Flash map + 1 MB storage partition	components `subsys/fs` +1.8 KB `subsys/storage` +0.2 KB `app (application code)` +0.1 KB / RAM +0.1 KB `drivers/flash` +0.1 KB `subsys/crc` +0.1 KB	ok
Settings on NVS `cat.store.settings_nvs`	Storage storage	+2.0 KB	+0.1 KB	120.4 KB	37.9 KB	15%	`cat.store.nvs` NVS key-value store	components `subsys/settings` +1.6 KB / RAM +0.1 KB `subsys/storage` +0.2 KB `app (application code)` +0.1 KB / RAM +0.0 KB `drivers/flash` +0.1 KB `(merged strings)` +0.1 KB	ok
Settings shell commands `cat.store.settings_shell`	Storage storage	+1.6 KB	+0.0 KB	122.0 KB	37.9 KB	15%	`cat.store.settings_nvs` Settings on NVS	components `subsys/settings` +0.9 KB `(merged strings)` +0.6 KB `lib/utils` +0.2 KB `subsys/shell` +0.0 KB `(linker fill)` +0.0 KB	ok
Stream flash (buffered sequential writer) `cat.store.stream_flash`	Storage storage	+1.2 KB	+0.3 KB	115.6 KB	38.0 KB	15%	`cat.store.flash_map` Flash map + 1 MB storage partition	components `subsys/storage` +0.7 KB / RAM +0.0 KB `(merged strings)` +0.3 KB `app (application code)` +0.1 KB / RAM +0.3 KB `drivers/flash` +0.1 KB `(linker fill)` +0.0 KB	ok
Flash map + 1 MB storage partition `cat.store.flash_map`	Storage storage	+0.4 KB	+0.0 KB	114.4 KB	37.7 KB	15%	`cat.store.flash` Flash driver (FlexSPI NOR, read/erase/write)	Overlay adds a 1 MB storage partition at the end of the 8 MB FlexSPI NOR (0x700000). components `subsys/storage` +0.2 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
OSCORE (uoscore) object security for CoAP `cat.sec.oscore`	Security protocol	+33.7 KB	+10.4 KB	144.2 KB	43.0 KB	17%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	OSCORE context init and CoAP <-> OSCORE conversion; delta includes zcbor and the PSA algorithms the library selects (AES-CCM, HMAC, SHA-256, ECDH/ECDSA P-256). components `modules/mbedtls` +22.5 KB / RAM +9.5 KB `modules/uoscore-uedhoc` +9.1 KB / RAM +0.0 KB `modules/zcbor` +1.1 KB `(merged strings)` +0.9 KB `app (application code)` +0.2 KB / RAM +0.8 KB	ok
mbed TLS 1.3 client (AES128-GCM, ECDHE P-256) `cat.sec.mbedtls_tls13`	Security security	+28.9 KB	+9.4 KB	171.5 KB	43.9 KB	17%	`cat.sec.mbedtls_x509` mbed TLS X.509 certificate parse + verify	components `modules/mbedtls` +28.2 KB / RAM +8.6 KB `app (application code)` +0.7 KB / RAM +0.8 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB	ok
Zephyr crypto API on mbed TLS shim (AES-CBC) `cat.sec.crypto_mbedtls_shim`	Security security	+27.6 KB	+10.6 KB	133.6 KB	39.3 KB	15%	`cat.sec.csprng` CSPRNG API (sys_csrand_get on TRNG)	components `modules/mbedtls` +24.2 KB / RAM +9.9 KB `drivers/crypto` +1.8 KB / RAM +0.5 KB `(merged strings)` +0.9 KB `subsys/random` +0.2 KB / RAM +0.0 KB `lib/libc` +0.2 KB / RAM +0.0 KB	ok
mbed TLS 1.2 client (ECDHE-ECDSA-AES128-GCM) `cat.sec.mbedtls_tls12`	Security security	+25.1 KB	+9.4 KB	167.7 KB	43.9 KB	17%	`cat.sec.mbedtls_x509` mbed TLS X.509 certificate parse + verify	TLS 1.2 client library on a caller-supplied transport (no sockets); PSA ECDH, ECDSA, AES-GCM, SHA-256. components `modules/mbedtls` +24.2 KB / RAM +8.6 KB `app (application code)` +0.7 KB / RAM +0.8 KB `(merged strings)` +0.1 KB `(linker fill)` +0.0 KB	ok
JWT with ES-256 (PSA) `cat.sec.jwt_es256`	Security library	+19.5 KB	+1.5 KB	130.0 KB	34.1 KB	13%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	JSON Web Token builder and ECDSA P-256 signing; delta includes JSON library and PSA ECDSA. components `modules/mbedtls` +17.1 KB / RAM +1.0 KB `lib/utils` +1.4 KB `subsys/jwt` +0.6 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.5 KB `(merged strings)` +0.1 KB	ok
PSA ECDSA P-256 (mbed TLS ECP) `cat.sec.psa_ecdsa_p256`	Security security	+18.5 KB	+1.0 KB	129.5 KB	33.6 KB	13%	`cat.sec.psa_sha256` PSA SHA-256	components `modules/mbedtls` +18.3 KB / RAM +1.0 KB `app (application code)` +0.2 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
JWT with RS-256 (PSA) `cat.sec.jwt_rs256`	Security library	+16.9 KB	+37.4 KB	127.4 KB	70.0 KB	27%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +14.4 KB / RAM +36.9 KB `lib/utils` +1.4 KB `subsys/jwt` +0.6 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.5 KB `(merged strings)` +0.1 KB	ok
PSA ECDH P-256 `cat.sec.psa_ecdh_p256`	Security security	+16.7 KB	+1.0 KB	127.2 KB	33.6 KB	13%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +16.5 KB / RAM +1.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
PSA Internal Trusted Storage on settings/NVS `cat.sec.psa_its`	Security security	+13.3 KB	+12.9 KB	133.6 KB	50.8 KB	20%	`cat.store.settings_nvs` Settings on NVS	Secure storage subsystem (AES-GCM transform, settings store). Delta includes the PSA Crypto core, entropy and AES-GCM, because the parent has none. components `modules/mbedtls` +9.9 KB / RAM +9.8 KB `subsys/secure_storage` +1.6 KB / RAM +0.0 KB `modules/hal_nxp` +0.8 KB `(merged strings)` +0.2 KB `subsys/random` +0.2 KB / RAM +0.0 KB	ok
ML-DSA-87 post-quantum signature (mldsa-native) `cat.sec.mldsa87`	Security security	+13.1 KB	+11.8 KB	123.6 KB	44.4 KB	17%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	Experimental TF-PSA-Crypto PQCP driver; keygen, sign, verify through mldsa-native functions (not yet in the PSA API). Static key and signature buffers (12 KB) are RAM. components `modules/mbedtls` +12.9 KB `app (application code)` +0.2 KB / RAM +11.8 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
mbed TLS X.509 certificate parse + verify `cat.sec.mbedtls_x509`	Security security	+13.1 KB	+0.9 KB	142.6 KB	34.5 KB	13%	`cat.sec.psa_ecdsa_p256` PSA ECDSA P-256 (mbed TLS ECP)	components `modules/mbedtls` +10.4 KB `(merged strings)` +2.0 KB `app (application code)` +0.6 KB / RAM +1.0 KB `(linker fill)` +0.0 KB	ok
PSA RSA-2048 PKCS#1 v1.5 verify `cat.sec.psa_rsa_verify`	Security security	+12.0 KB	+8.2 KB	123.0 KB	40.8 KB	16%	`cat.sec.psa_sha256` PSA SHA-256	components `modules/mbedtls` +11.3 KB / RAM +8.2 KB `app (application code)` +0.7 KB `(merged strings)` +0.0 KB	ok
PSA ECDH X25519 `cat.sec.psa_x25519`	Security security	+11.9 KB	+1.0 KB	122.4 KB	33.6 KB	13%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +11.7 KB / RAM +1.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
PSA AES-128-CBC `cat.sec.psa_aes_cbc`	Security security	+8.1 KB	+9.1 KB	118.6 KB	41.6 KB	16%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +7.8 KB / RAM +9.0 KB `app (application code)` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `(linker fill)` +0.0 KB	ok
PSA AES-128-GCM `cat.sec.psa_aes_gcm`	Security security	+8.0 KB	+9.1 KB	118.5 KB	41.6 KB	16%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +7.7 KB / RAM +9.0 KB `app (application code)` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
PSA AES-128-CCM `cat.sec.psa_aes_ccm`	Security security	+7.2 KB	+9.1 KB	117.7 KB	41.6 KB	16%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +7.0 KB / RAM +9.0 KB `app (application code)` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
PSA ECDSA P-256 (p256-m driver) `cat.sec.psa_ecdsa_p256m`	Security security	+6.5 KB	+1.0 KB	117.4 KB	33.6 KB	13%	`cat.sec.psa_sha256` PSA SHA-256	Same API calls as cat.sec.psa_ecdsa_p256, implemented by the small p256-m driver. components `modules/mbedtls` +6.2 KB / RAM +1.0 KB `app (application code)` +0.2 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
PSA ChaCha20-Poly1305 `cat.sec.psa_chachapoly`	Security security	+5.1 KB	+0.5 KB	115.6 KB	33.1 KB	13%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +4.8 KB / RAM +0.4 KB `app (application code)` +0.3 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random `cat.sec.psa_base`	Security security	+4.5 KB	+3.9 KB	110.5 KB	32.6 KB	13%	`cat.sec.csprng` CSPRNG API (sys_csrand_get on TRNG)	PSA Crypto API provider with no algorithm enabled; psa_crypto_init and psa_generate_random on the CSPRNG. components `modules/mbedtls` +4.0 KB / RAM +0.8 KB `subsys/random` +0.2 KB / RAM +0.0 KB `lib/libc` +0.2 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
DCP hardware crypto (AES-CBC, SHA-256) via crypto API `cat.sec.dcp`	Security driver	+4.3 KB	+0.8 KB	109.1 KB	29.5 KB	12%	`app` Reference app	NXP Data Co-Processor driver (CRYPTO_MCUX_DCP) behind the Zephyr crypto API. components `modules/hal_nxp` +2.9 KB / RAM +0.2 KB `drivers/crypto` +1.0 KB / RAM +0.6 KB `app (application code)` +0.3 KB / RAM +0.1 KB `arch (Cortex-M7)` +0.1 KB `(merged strings)` +0.0 KB	ok
PSA HMAC-SHA-256 `cat.sec.psa_hmac`	Security security	+3.2 KB	+0.4 KB	114.2 KB	33.0 KB	13%	`cat.sec.psa_sha256` PSA SHA-256	components `modules/mbedtls` +3.0 KB / RAM +0.4 KB `app (application code)` +0.2 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
PSA HKDF-SHA-256 `cat.sec.psa_hkdf`	Security security	+1.7 KB	+0.0 KB	115.9 KB	33.0 KB	13%	`cat.sec.psa_hmac` PSA HMAC-SHA-256	components `modules/mbedtls` +1.5 KB `app (application code)` +0.2 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
Entropy driver (TRNG) `cat.sec.entropy_trng`	Security driver	+1.1 KB	+0.0 KB	105.9 KB	28.7 KB	11%	`app` Reference app	components `modules/hal_nxp` +0.8 KB `drivers/entropy` +0.1 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
PSA SHA-256 `cat.sec.psa_sha256`	Security security	+0.5 KB	+0.0 KB	111.0 KB	32.6 KB	13%	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	components `modules/mbedtls` +0.4 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB	ok
CSPRNG API (sys_csrand_get on TRNG) `cat.sec.csprng`	Security security	+0.1 KB	+0.0 KB	106.0 KB	28.7 KB	11%	`cat.sec.entropy_trng` Entropy driver (TRNG)	components `app (application code)` +0.1 KB `subsys/random` +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
EDHOC (uedhoc) key exchange `cat.sec.edhoc`	Security protocol	–	–	–	–	–	`cat.sec.psa_base` PSA Crypto core (mbed TLS / TF-PSA-Crypto) + random	EDHOC initiator; delta includes zcbor, the PSA algorithms the library selects and mbed TLS X.509 (cert.c uses the legacy mbed TLS PK identifiers, so MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS is needed).	not available: uedhoc src/edhoc/cert.c uses the mbed TLS 3 PK API (MBEDTLS_PK_ECDSA, mbedtls_x509_crt sig_pk). Zephyr v4.4.2 ships mbed TLS 4 / TF-PSA-Crypto, where these identifiers are private and not reachable from x509_crt.h, even with MBEDTLS_X509_CRT_PARSE_C and MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS. The module does not compile.
Userspace (MPU-based user mode) `cat.dbg.userspace`	OS services & debug debug	+49.5 KB	+7.4 KB	154.3 KB	36.1 KB	14%	`app` Reference app	CONFIG_USERSPACE on the ARMv7-M MPU; adds syscall marshalling, the kernel object table (gperf-generated) and the privileged-stack and MPU-partition handling. No user thread yet. components `kernel` +19.2 KB / RAM +0.2 KB `drivers/serial` +4.7 KB `subsys/usb` +3.9 KB / RAM +0.0 KB `(merged strings)` +3.5 KB `drivers/gpio` +3.0 KB	ok
MCUmgr image group (DFU upload to slot1) `cat.sys.mcumgr_img`	OS services & debug os-service	+16.7 KB	+9.7 KB	127.6 KB	43.0 KB	17%	`cat.sys.mcumgr_shell` MCUmgr SMP over shell transport + OS group	Image manager, stream flash and MCUboot bootutil library; overlay adds image-0 (code, 3 MB) and image-1 (3 MB) slots. HalfKay does not swap slots, so on the real board this only stores an image. components `drivers/flash` +5.2 KB / RAM +5.1 KB `subsys/mgmt` +3.8 KB / RAM +0.6 KB `modules/hal_nxp` +2.7 KB / RAM +2.7 KB `(merged strings)` +1.2 KB `drivers/memc` +1.1 KB / RAM +1.0 KB	ok
Tracing CTF format, RAM backend `cat.dbg.tracing_ctf_ram`	OS services & debug debug	+16.1 KB	+7.5 KB	120.9 KB	36.2 KB	14%	`app` Reference app	components `subsys/tracing` +14.5 KB / RAM +7.4 KB `kernel` +1.1 KB `drivers/gpio` +0.2 KB `app (application code)` +0.2 KB / RAM +0.0 KB `(linker fill)` +0.1 KB	ok
Tracing CTF format, UART backend (LPUART6) `cat.dbg.tracing_ctf_uart`	OS services & debug debug	+16.0 KB	+3.5 KB	120.9 KB	32.2 KB	13%	`app` Reference app	Hardware: USB-serial adapter on Teensy pins 0/1 components `subsys/tracing` +14.4 KB / RAM +3.4 KB `kernel` +1.1 KB `drivers/gpio` +0.2 KB `app (application code)` +0.2 KB / RAM +0.0 KB `(linker fill)` +0.1 KB	ok
SEGGER SystemView tracing over RTT `cat.dbg.systemview`	OS services & debug debug	+9.9 KB	+5.6 KB	114.1 KB	34.3 KB	13%	`abl.gpio_get_dir_cfg` GPIO get-direction/get-config API	Parent is the app without GPIO_GET_DIRECTION (same v4.4.2 gpio.h tracing macro bug as cat.dbg.tracing_user). Hardware: SWD debug probe (see cat.dbg.segger_rtt) components `modules/segger` +4.6 KB / RAM +5.5 KB `kernel` +1.2 KB `subsys/usb` +1.1 KB / RAM +0.0 KB `arch (Cortex-M7)` +0.6 KB `(merged strings)` +0.5 KB	ok
Sensing subsystem (1 phy 3D sensor) `cat.sys.sensing`	OS services & debug os-service	+8.9 KB	+14.0 KB	119.6 KB	43.0 KB	17%	`cat.sys.sensor_bmi160` BMI160 IMU on LPI2C1 (sensing parent)	The sensing subsystem allocates connections with k_malloc; a 2 KB system heap is part of the delta. Hardware: BMI160 IMU on Teensy pins 18 (SDA) / 19 (SCL) components `subsys/sensing` +5.1 KB / RAM +10.4 KB `(merged strings)` +1.5 KB `subsys/rtio` +1.3 KB / RAM +1.5 KB `lib/utils` +0.8 KB `app (application code)` +0.1 KB	ok
POSIX_API umbrella (all PSE51-type options) `cat.sys.posix_api`	OS services & debug os-service	+8.0 KB	+6.9 KB	112.8 KB	35.6 KB	14%	`app` Reference app	CONFIG_POSIX_API alone; the stubs of the three POSIX variants above call the API. components `lib/posix` +4.4 KB / RAM +5.9 KB `kernel` +1.3 KB / RAM +0.7 KB `lib/utils` +0.7 KB `lib/os` +0.6 KB `app (application code)` +0.4 KB / RAM +0.1 KB	ok
MCUmgr SMP over 2nd USB CDC-ACM + OS group `cat.sys.mcumgr_usb`	OS services & debug os-service	+6.6 KB	+6.9 KB	111.4 KB	35.6 KB	14%	`app` Reference app	SMP UART transport on a second CDC-ACM interface (zephyr,uart-mcumgr); OS group. components `subsys/mgmt` +2.5 KB / RAM +4.1 KB `modules/zcbor` +1.8 KB `lib/utils` +0.7 KB `subsys/usb` +0.5 KB / RAM +3.5 KB `drivers/console` +0.5 KB / RAM +0.3 KB	ok
MCUmgr SMP over shell transport + OS group `cat.sys.mcumgr_shell`	OS services & debug os-service	+6.1 KB	+4.7 KB	110.9 KB	33.4 KB	13%	`app` Reference app	SMP frames tunnelled in the existing USB CDC-ACM shell; OS group (echo, reset, taskstat, info). components `subsys/mgmt` +2.9 KB / RAM +4.1 KB `modules/zcbor` +1.8 KB `lib/utils` +0.7 KB `arch (Cortex-M7)` +0.2 KB `(merged strings)` +0.2 KB	ok
MCUmgr SMP shell + OS group (on LittleFS parent) `cat.sys.mcumgr_base_lfs`	OS services & debug os-service	+6.1 KB	+4.7 KB	141.9 KB	44.0 KB	17%	`cat.store.littlefs` LittleFS on flash (VFS + littlefs)	Same as cat.sys.mcumgr_shell, built on the LittleFS variant; parent of the fs group variant. components `subsys/mgmt` +2.9 KB / RAM +4.1 KB `modules/zcbor` +1.8 KB `lib/utils` +0.7 KB `arch (Cortex-M7)` +0.2 KB `(merged strings)` +0.2 KB	ok
Dictionary logging on the UART backend `cat.dbg.log_dictionary`	OS services & debug debug	+5.9 KB	+0.0 KB	111.0 KB	28.8 KB	11%	`cat.dbg.log_uart` Log UART backend on LPUART6 (text)	Binary dictionary output; strings stay on the host (log_parser.py with the build database). components `subsys/usb` +5.8 KB `(merged strings)` -4.1 KB `arch (Cortex-M7)` +1.3 KB `drivers/usb` +0.7 KB `kernel` +0.6 KB	ok
BMI160 IMU on LPI2C1 (sensing parent) `cat.sys.sensor_bmi160`	OS services & debug driver	+5.8 KB	+0.2 KB	110.6 KB	29.0 KB	11%	`app` Reference app	LPI2C1 (pins 18/19) driver, sensor API and BMI160 driver; parent of the sensing variant. Hardware: BMI160 IMU on Teensy pins 18 (SDA) / 19 (SCL) components `drivers/sensor` +2.9 KB / RAM +0.1 KB `modules/hal_nxp` +1.7 KB / RAM +0.0 KB `drivers/i2c` +0.9 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `drivers/clock_control` +0.1 KB	ok
Core dump to flash partition + shell `cat.dbg.coredump_flash`	OS services & debug debug	+5.6 KB	+0.4 KB	120.0 KB	38.1 KB	15%	`cat.store.flash_map` Flash map + 1 MB storage partition	Overlay adds a 64 KB coredump partition below the storage partition. components `subsys/debug` +2.8 KB / RAM +0.3 KB `(merged strings)` +1.7 KB `subsys/storage` +0.7 KB / RAM +0.0 KB `arch (Cortex-M7)` +0.2 KB / RAM +0.1 KB `drivers/flash` +0.1 KB	ok
FPU on (hard-float context switching) `cat.sys.fpu`	OS services & debug os-service	+5.1 KB	+1.2 KB	110.0 KB	30.0 KB	12%	`app` Reference app	The app builds without CONFIG_FPU. DSP, ML and LC3 variants need it and use this parent. components `toolchain libs (libc, libgcc)` +4.6 KB `arch (Cortex-M7)` +0.4 KB `(merged strings)` +0.1 KB `modules/hal_nxp` +0.1 KB `kernel` -0.0 KB / RAM +0.6 KB	ok
POSIX threads, mutex, condvar `cat.sys.posix_threads`	OS services & debug os-service	+3.7 KB	+1.8 KB	108.5 KB	30.5 KB	12%	`app` Reference app	In v4.4.2 pthread_cond_timedwait uses timespec_to_timeoutms(), which builds only with POSIX_TIMERS, so POSIX timers are part of the delta. components `lib/posix` +2.4 KB / RAM +1.5 KB `lib/utils` +0.7 KB `kernel` +0.3 KB / RAM +0.3 KB `app (application code)` +0.1 KB / RAM +0.0 KB `(merged strings)` +0.1 KB	ok
Stack canaries strong (-fstack-protector-strong) `cat.dbg.stack_canaries_strong`	OS services & debug debug	+3.5 KB	+0.0 KB	109.5 KB	28.7 KB	11%	`cat.sec.entropy_trng` Entropy driver (TRNG)	components `subsys/shell` +1.2 KB `kernel` +0.4 KB / RAM +0.0 KB `drivers/usb` +0.3 KB `drivers/gpio` +0.3 KB `subsys/logging` +0.2 KB	ok
MCUmgr file system group `cat.sys.mcumgr_fs`	OS services & debug os-service	+2.9 KB	+0.1 KB	144.8 KB	44.1 KB	17%	`cat.sys.mcumgr_base_lfs` MCUmgr SMP shell + OS group (on LittleFS parent)	components `subsys/mgmt` +2.0 KB / RAM +0.2 KB `subsys/fs` +0.5 KB `(merged strings)` +0.2 KB `kernel` +0.1 KB `modules/zcbor` +0.1 KB	ok
POSIX file I/O on LittleFS `cat.sys.posix_fs`	OS services & debug os-service	+2.8 KB	+0.5 KB	138.6 KB	39.9 KB	16%	`cat.store.littlefs` LittleFS on flash (VFS + littlefs)	open/read/write/lseek/fstat on the /lfs mount through ZVFS. The stub declares the prototypes, because v4.4.2 unistd.h declares them only with CONFIG_POSIX_API. components `lib/os` +1.6 KB / RAM +0.2 KB `subsys/fs` +0.3 KB `kernel` +0.3 KB / RAM +0.0 KB `lib/posix` +0.2 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.0 KB	ok
System power management (idle/suspend states) `cat.sys.pm`	OS services & debug os-service	+2.8 KB	+0.7 KB	107.6 KB	29.4 KB	11%	`app` Reference app	CONFIG_PM with the RT10xx power states from the SoC devicetree. components `subsys/pm` +1.2 KB / RAM +0.1 KB `SoC (i.MX RT)` +0.6 KB / RAM +0.6 KB `modules/hal_nxp` +0.3 KB `drivers/serial` +0.3 KB / RAM +0.0 KB `generated (ISR tables)` +0.1 KB / RAM +0.1 KB	ok
Log backend to file system (LittleFS) `cat.dbg.log_fs`	OS services & debug debug	+2.5 KB	+1.8 KB	138.4 KB	41.1 KB	16%	`cat.store.littlefs` LittleFS on flash (VFS + littlefs)	components `subsys/fs` +1.2 KB `subsys/logging` +1.0 KB / RAM +1.8 KB `(merged strings)` +0.3 KB `toolchain libs (libc, libgcc)` +0.0 KB `(linker fill)` +0.0 KB	ok
CMSIS-RTOS v2 API layer `cat.sys.cmsis_rtos_v2`	OS services & debug os-service	+2.4 KB	+5.1 KB	107.2 KB	33.8 KB	13%	`app` Reference app	CMSIS-RTOS v2 needs k_poll and at least 56 preemptive priorities; both are part of the delta. components `subsys/portability` +1.6 KB / RAM +4.8 KB `kernel` +0.4 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.0 KB `(merged strings)` +0.1 KB `drivers/usb` +0.1 KB / RAM +0.1 KB	ok
Device power management (+ runtime) `cat.sys.pm_device`	OS services & debug os-service	+2.1 KB	+0.0 KB	107.0 KB	28.7 KB	11%	`app` Reference app	components `subsys/pm` +1.4 KB / RAM +0.0 KB `subsys/shell` +0.2 KB `(merged strings)` +0.2 KB `kernel` +0.2 KB `drivers/serial` +0.1 KB	ok
POSIX clocks, nanosleep, timers `cat.sys.posix_timers`	OS services & debug os-service	+2.1 KB	+3.8 KB	110.6 KB	34.3 KB	13%	`cat.sys.posix_threads` POSIX threads, mutex, condvar	Parent has pthreads and POSIX_TIMERS (pthreads need them in v4.4.2); POSIX_CLOCK_SELECTION (clock_nanosleep) does not compile without pthreads. Delta = clock selection + the clock/timer code the stub reaches. components `lib/posix` +1.2 KB / RAM +3.8 KB `lib/os` +0.6 KB `app (application code)` +0.2 KB `kernel` +0.1 KB `(merged strings)` +0.0 KB	ok
Retained RAM + retention + boot mode `cat.sys.retention_bootmode`	OS services & debug os-service	+2.0 KB	+0.1 KB	106.9 KB	28.8 KB	11%	`app` Reference app	Overlay takes the last 4 KB of OCRAM2 as a retained-RAM region with a 256 B retention area used as zephyr,boot-mode. components `subsys/retention` +1.1 KB / RAM +0.0 KB `drivers/retained_mem` +0.3 KB / RAM +0.0 KB `(merged strings)` +0.2 KB `subsys/crc` +0.2 KB `app (application code)` +0.1 KB	ok
SEGGER RTT console + log backend `cat.dbg.segger_rtt`	OS services & debug debug	+2.0 KB	+1.2 KB	106.8 KB	29.9 KB	12%	`app` Reference app	Hardware: SWD debug probe; Teensy 4.1 does not break out SWD (the MKL02 helper uses JTAG), so RTT needs a board modification components `modules/segger` +1.5 KB / RAM +1.2 KB `subsys/logging` +0.4 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
hwinfo shell commands `cat.sys.hwinfo_shell`	OS services & debug os-service	+1.6 KB	+0.0 KB	106.7 KB	28.7 KB	11%	`cat.sys.hwinfo` hwinfo (OCOTP unique ID, SRC reset cause)	components `drivers/hwinfo` +1.0 KB `(merged strings)` +0.6 KB `(linker fill)` +0.0 KB	ok
RTIO (real-time I/O queues) `cat.sys.rtio`	OS services & debug os-service	+1.4 KB	+0.4 KB	106.3 KB	29.1 KB	11%	`app` Reference app	components `subsys/rtio` +1.0 KB / RAM +0.0 KB `app (application code)` +0.4 KB / RAM +0.4 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Input subsystem + gpio-keys (1 button) `cat.sys.input_gpio_keys`	OS services & debug os-service	+1.4 KB	+1.6 KB	106.2 KB	30.3 KB	12%	`app` Reference app	Overlay adds a gpio-keys node with one key on Teensy pin 2 (GPIO4_IO04, active low, pull-up). Hardware: Push button between Teensy pin 2 and GND components `drivers/input` +0.7 KB / RAM +0.1 KB `subsys/input` +0.3 KB / RAM +1.5 KB `(merged strings)` +0.3 KB `app (application code)` +0.1 KB / RAM +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
Thread analyzer (stack + runtime stats) `cat.dbg.thread_analyzer`	OS services & debug debug	+1.3 KB	+0.2 KB	106.1 KB	28.9 KB	11%	`app` Reference app	components `kernel` +0.6 KB / RAM +0.1 KB `subsys/debug` +0.3 KB / RAM +0.0 KB `(merged strings)` +0.3 KB `subsys/shell` +0.1 KB / RAM +0.0 KB `app (application code)` +0.0 KB / RAM +0.0 KB	ok
Hardware watchdog (WDOG1) `cat.dbg.hw_wdt`	OS services & debug driver	+1.2 KB	+0.0 KB	106.1 KB	28.7 KB	11%	`app` Reference app	components `drivers/watchdog` +0.5 KB / RAM +0.0 KB `modules/hal_nxp` +0.3 KB `(merged strings)` +0.3 KB `app (application code)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
Task watchdog (software, no HW fallback) `cat.dbg.task_wdt`	OS services & debug os-service	+1.2 KB	+0.2 KB	106.0 KB	28.9 KB	11%	`app` Reference app	components `subsys/task_wdt` +0.6 KB / RAM +0.2 KB `arch (Cortex-M7)` +0.2 KB `(merged strings)` +0.2 KB `zephyr-core` +0.1 KB `app (application code)` +0.1 KB	ok
Task watchdog with WDOG1 fallback `cat.dbg.task_wdt_hw`	OS services & debug os-service	+1.1 KB	+0.2 KB	107.2 KB	28.9 KB	11%	`cat.dbg.hw_wdt` Hardware watchdog (WDOG1)	components `subsys/task_wdt` +0.6 KB / RAM +0.2 KB `arch (Cortex-M7)` +0.2 KB `zephyr-core` +0.1 KB `(merged strings)` +0.1 KB `app (application code)` +0.1 KB	ok
MCUmgr statistics group `cat.sys.mcumgr_stat`	OS services & debug os-service	+1.1 KB	+0.0 KB	112.1 KB	33.4 KB	13%	`cat.sys.mcumgr_shell` MCUmgr SMP over shell transport + OS group	components `subsys/mgmt` +0.8 KB / RAM +0.0 KB `subsys/stats` +0.2 KB / RAM +0.0 KB `(merged strings)` +0.1 KB `modules/zcbor` +0.1 KB `(linker fill)` -0.0 KB	ok
zbus message bus (listener + subscriber) `cat.sys.zbus`	OS services & debug os-service	+1.0 KB	+0.1 KB	105.9 KB	28.8 KB	11%	`app` Reference app	components `subsys/zbus` +0.6 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `kernel` +0.0 KB `(linker fill)` +0.0 KB	ok
POSIX semaphores (unnamed + named) `cat.sys.posix_sem`	OS services & debug os-service	+1.0 KB	+0.4 KB	105.8 KB	29.1 KB	11%	`app` Reference app	components `lib/posix` +0.7 KB / RAM +0.0 KB `app (application code)` +0.1 KB / RAM +0.0 KB `kernel` +0.1 KB / RAM +0.3 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Core dump to log backend `cat.dbg.coredump_log`	OS services & debug debug	+0.9 KB	+0.2 KB	105.7 KB	28.9 KB	11%	`app` Reference app	components `subsys/debug` +0.6 KB / RAM +0.1 KB `arch (Cortex-M7)` +0.2 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `lib/utils` +0.0 KB `kernel` +0.0 KB	ok
User tracing hooks `cat.dbg.tracing_user`	OS services & debug debug	+0.9 KB	+0.1 KB	105.0 KB	28.8 KB	11%	`abl.gpio_get_dir_cfg` GPIO get-direction/get-config API	Parent is the app without GPIO_GET_DIRECTION, because in v4.4.2 gpio.h does not compile with the user tracing macros when GPIO_GET_DIRECTION=y (argument mismatch in sys_port_trace_gpio_port_get_direction_*). components `subsys/tracing` +0.2 KB `kernel` +0.2 KB `drivers/gpio` +0.2 KB `app (application code)` +0.2 KB / RAM +0.0 KB `arch (Cortex-M7)` +0.0 KB	ok
SMF state machine framework (hierarchical) `cat.sys.smf`	OS services & debug os-service	+0.8 KB	+0.0 KB	105.7 KB	28.7 KB	11%	`app` Reference app	components `lib/smf` +0.6 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.0 KB `(merged strings)` +0.1 KB	ok
Stack canaries (-fstack-protector) `cat.dbg.stack_canaries`	OS services & debug debug	+0.8 KB	+0.0 KB	106.8 KB	28.7 KB	11%	`cat.sec.entropy_trng` Entropy driver (TRNG)	The canary seed needs an entropy driver, so the parent is the TRNG variant. components `kernel` +0.2 KB / RAM +0.0 KB `subsys/shell` +0.2 KB `subsys/usb` +0.1 KB `lib/os` +0.1 KB `app (application code)` +0.1 KB	ok
libc malloc arena (default size) `cat.sys.malloc`	OS services & debug os-service	+0.8 KB	+0.0 KB	105.6 KB	28.7 KB	11%	`app` Reference app	Picolibc malloc on the common libc arena. Default arena size -1 takes all free RAM at boot, so the linker summary shows only the code. components `lib/heap` +0.5 KB `lib/libc` +0.2 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
One user-mode thread in a memory domain + syscall `cat.dbg.userspace_thread`	OS services & debug debug	+0.6 KB	+2.1 KB	154.9 KB	38.2 KB	15%	`cat.dbg.userspace` Userspace (MPU-based user mode)	k_mem_domain with one app partition, a K_USER thread with a 1 KB stack, k_object_access_grant on a semaphore and k_sem_give from user mode. components `app (application code)` +0.4 KB / RAM +1.4 KB `(linker fill)` +0.1 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `generated (ISR tables)` +0.0 KB / RAM +1.1 KB `kernel` +0.0 KB	ok
Input shell commands `cat.sys.input_shell`	OS services & debug os-service	+0.5 KB	+0.0 KB	106.8 KB	30.3 KB	12%	`cat.sys.input_gpio_keys` Input subsystem + gpio-keys (1 button)	components `subsys/input` +0.3 KB `(merged strings)` +0.1 KB `subsys/shell` +0.1 KB `(linker fill)` +0.0 KB	ok
sys_reboot `cat.sys.reboot`	OS services & debug os-service	+0.5 KB	+0.0 KB	105.3 KB	28.7 KB	11%	`app` Reference app	components `arch (Cortex-M7)` +0.2 KB `zephyr-core` +0.1 KB `(merged strings)` +0.1 KB `app (application code)` +0.0 KB `drivers/timer` +0.0 KB	ok
Second shell on LPUART6 (pins 0/1) `cat.sys.shell_uart2`	OS services & debug os-service	+0.4 KB	+3.8 KB	105.2 KB	32.5 KB	13%	`app` Reference app	Extra shell instance on the serial UART transport next to the USB CDC-ACM shell; started by a command. Hardware: USB-serial adapter on Teensy pins 0 (RX1) and 1 (TX1) components `app (application code)` +0.3 KB / RAM +3.8 KB `(merged strings)` +0.1 KB	ok
Timing functions (DWT cycle counter) `cat.sys.timing`	OS services & debug os-service	+0.4 KB	+0.0 KB	105.2 KB	28.7 KB	11%	`app` Reference app	components `arch (Cortex-M7)` +0.1 KB `subsys/timing` +0.1 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Log UART backend on LPUART6 (text) `cat.dbg.log_uart`	OS services & debug debug	+0.3 KB	+0.1 KB	105.1 KB	28.8 KB	11%	`app` Reference app	Second log backend on LPUART6 (zephyr,log-uart) next to the shell log backend. Hardware: USB-serial adapter on Teensy pins 0/1 components `subsys/logging` +0.3 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
hwinfo (OCOTP unique ID, SRC reset cause) `cat.sys.hwinfo`	OS services & debug driver	+0.2 KB	+0.0 KB	105.1 KB	28.7 KB	11%	`app` Reference app	components `drivers/hwinfo` +0.1 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `modules/hal_nxp` +0.0 KB `(linker fill)` -0.0 KB	ok
CPU load measurement `cat.dbg.cpu_load`	OS services & debug debug	+0.2 KB	+0.1 KB	105.1 KB	28.8 KB	11%	`app` Reference app	components `subsys/debug` +0.1 KB / RAM +0.0 KB `arch (Cortex-M7)` +0.0 KB `drivers/usb` +0.0 KB / RAM +0.1 KB `subsys/usb` +0.0 KB / RAM +0.0 KB `subsys/tracing` +0.0 KB	ok
System heap 8 KB (k_malloc) `cat.sys.k_malloc`	OS services & debug os-service	+0.2 KB	+8.1 KB	105.0 KB	36.8 KB	14%	`app` Reference app	components `kernel` +0.1 KB / RAM +8.1 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
Static 8 KB k_heap `cat.sys.k_heap`	OS services & debug os-service	+0.1 KB	+8.0 KB	105.0 KB	36.7 KB	14%	`app` Reference app	components `app (application code)` +0.1 KB / RAM +8.0 KB `(merged strings)` +0.0 KB	ok
libc malloc arena fixed at 16 KB `cat.sys.malloc_16k`	OS services & debug os-service	-0.0 KB	+16.0 KB	105.6 KB	44.7 KB	17%	`cat.sys.malloc` libc malloc arena (default size)	components `lib/libc` -0.0 KB / RAM +16.0 KB	ok
Stack sentinel instead of MPU stack guard `cat.dbg.stack_sentinel`	OS services & debug debug	-0.2 KB	-0.6 KB	104.7 KB	28.1 KB	11%	`app` Reference app	The sentinel excludes the MPU stack guard, so the delta is sentinel minus MPU guard (HW stack protection off). components `arch (Cortex-M7)` -0.2 KB / RAM -0.0 KB `kernel` +0.0 KB / RAM -0.2 KB `(linker fill)` -0.0 KB `app (application code)` +0.0 KB / RAM -0.1 KB `subsys/logging` +0.0 KB / RAM -0.1 KB	ok
App built as MCUboot-chainloadable image `cat.sys.mcuboot_chainload`	OS services & debug os-service	-6.2 KB	+0.0 KB	121.4 KB	43.0 KB	17%	`cat.sys.mcumgr_img` MCUmgr image group (DFU upload to slot1)	CONFIG_BOOTLOADER_MCUBOOT=y; code links into image-0 (zephyr,code-partition from the parent). Only the app side; MCUboot itself is a separate sysbuild image that this runner does not build. components `(linker fill)` -6.5 KB `boards` -0.5 KB `subsys/dfu` +0.3 KB `arch (Cortex-M7)` +0.2 KB `subsys/storage` +0.2 KB	ok
MCUboot bootloader `cat.sys.mcuboot`	OS services & debug os-service	–	–	–	–	–	`app` Reference app		not available: MCUboot is a separate sysbuild image; the runner builds only app/. On Teensy 4.1 the HalfKay loader (on the MKL02 helper MCU) writes the image at 0x60000000 and the ROM boots it from the FlexSPI boot header, so MCUboot would have to own offset 0 and the app would move to a slot; teensy_loader_cli cannot write slots. See cat.sys.mcuboot_chainload for the app-side cost.
LVGL (label + button, 16 KB pool) `cat.ui.lvgl`	Libraries, ML & UI ui	+211.9 KB	+34.6 KB	317.1 KB	63.4 KB	25%	`cat.ui.display_dummy` Display API + dummy display controller	components `modules/lvgl` +209.5 KB / RAM +31.6 KB `(merged strings)` +1.7 KB `lib/heap` +0.5 KB `app (application code)` +0.1 KB `toolchain libs (libc, libgcc)` +0.1 KB	ok
LC3 audio codec (encode + decode, 48 kHz) `cat.ml.lc3`	Libraries, ML & UI ml-dsp	+102.9 KB	+15.9 KB	212.9 KB	45.8 KB	18%	`cat.sys.fpu` FPU on (hard-float context switching)	components `modules/liblc3` +102.7 KB / RAM +0.6 KB `app (application code)` +0.2 KB / RAM +15.2 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
CMSIS-DSP (FIR, real FFT, statistics; f32) `cat.ml.cmsis_dsp`	Libraries, ML & UI ml-dsp	+81.8 KB	+3.4 KB	191.8 KB	33.3 KB	13%	`cat.sys.fpu` FPU on (hard-float context switching)	components `modules/cmsis-dsp` +81.6 KB `app (application code)` +0.1 KB / RAM +3.3 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Apache Thrift (binary protocol, memory transport) `cat.lib.thrift`	Libraries, ML & UI library	+74.1 KB	+18.7 KB	228.9 KB	86.1 KB	34%	`cat.net.base` TCP (net base = IPv4 + UDP + TCP + sockets)	Thrift C++ library with POSIX_API, libstdc++, exceptions and C++17; delta includes those prerequisites. The stub serialises a struct by hand on a TMemoryBuffer (no generated code). The module gives its include paths to the app only through thrift.cmake, which the app CMakeLists does not call, so CONFIG_COMPILER_OPT passes them through the response file study/stubs/sys/thrift_includes.rsp (paths relative to the build directory). components `toolchain libs (libc, libgcc)` +30.5 KB / RAM +0.4 KB `app (application code)` +11.3 KB / RAM +0.0 KB `subsys/net` +5.7 KB / RAM +0.1 KB `(merged strings)` +5.3 KB `subsys/shell` +3.5 KB / RAM +0.0 KB	ok
C++ exceptions `cat.lib.cpp_exceptions`	Libraries, ML & UI library	+35.1 KB	+0.2 KB	142.8 KB	28.9 KB	11%	`cat.lib.libstdcpp` Full C++ standard library (libstdc++)	components `toolchain libs (libc, libgcc)` +17.1 KB / RAM +0.1 KB `subsys/shell` +3.4 KB `(merged strings)` +3.3 KB `subsys/usb` +1.9 KB `kernel` +1.5 KB	ok
TensorFlow Lite Micro (hello_world sine model) `cat.ml.tflm`	Libraries, ML & UI ml-dsp	+26.0 KB	+5.2 KB	136.0 KB	35.2 KB	14%	`cat.sys.fpu` FPU on (hard-float context switching)	TFLM interpreter, reference FULLY_CONNECTED kernel, 2.5 KB model, 2 KB arena; includes the full C++ library that TFLM selects. components `modules/tflite-micro` +16.3 KB / RAM +0.0 KB `(merged strings)` +6.4 KB `app (application code)` +2.9 KB / RAM +2.2 KB `toolchain libs (libc, libgcc)` +0.3 KB `lib/libc` +0.1 KB / RAM +0.0 KB	ok
TensorFlow Lite Micro with CMSIS-NN kernels `cat.ml.tflm_cmsis_nn`	Libraries, ML & UI ml-dsp	+13.6 KB	+0.0 KB	149.6 KB	35.2 KB	14%	`cat.ml.tflm` TensorFlow Lite Micro (hello_world sine model)	components `modules/cmsis-nn` +12.9 KB `(merged strings)` +1.4 KB `modules/tflite-micro` -0.7 KB `(linker fill)` -0.0 KB	ok
CMSIS-NN (int8 fully connected + softmax) `cat.ml.cmsis_nn`	Libraries, ML & UI ml-dsp	+7.6 KB	+1.2 KB	117.5 KB	31.2 KB	12%	`cat.sys.fpu` FPU on (hard-float context switching)	components `modules/cmsis-nn` +7.3 KB `app (application code)` +0.3 KB / RAM +1.2 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Float printf (cbprintf + picolibc) `cat.lib.printf_float`	Libraries, ML & UI library	+6.7 KB	+0.0 KB	111.5 KB	28.7 KB	11%	`app` Reference app	components `toolchain libs (libc, libgcc)` +6.5 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
nanopb (Protocol Buffers) `cat.lib.nanopb`	Libraries, ML & UI library	+6.2 KB	+0.0 KB	111.1 KB	28.7 KB	11%	`app` Reference app	nanopb runtime (pb_common, pb_encode, pb_decode) and one 3-field message. The message code is pre-generated with protoc and nanopb_generator.py into study/stubs/sys/nanopb/, because the app CMakeLists does not call zephyr_nanopb_sources(); the regeneration command is in study.proto. components `modules/nanopb` +5.4 KB `(merged strings)` +0.6 KB `app (application code)` +0.2 KB `(linker fill)` +0.0 KB	ok
JSON library (descriptor parse/encode) `cat.lib.json`	Libraries, ML & UI library	+4.8 KB	+0.0 KB	109.7 KB	28.7 KB	11%	`app` Reference app	components `lib/utils` +4.2 KB `toolchain libs (libc, libgcc)` +0.3 KB `app (application code)` +0.2 KB `(merged strings)` +0.1 KB	ok
Full C++ standard library (libstdc++) `cat.lib.libstdcpp`	Libraries, ML & UI library	+2.8 KB	+0.0 KB	107.7 KB	28.7 KB	11%	`app` Reference app	GLIBCXX_LIBCPP instead of the minimal libc++; the stub uses vector, map, string, sort, to_string. components `app (application code)` +1.8 KB `toolchain libs (libc, libgcc)` +0.6 KB / RAM +0.0 KB `(merged strings)` +0.3 KB `lib/libc` +0.2 KB / RAM +0.0 KB `(linker fill)` -0.0 KB	ok
sys_hashmap (separate chaining) `cat.lib.hashmap`	Libraries, ML & UI library	+1.8 KB	+0.1 KB	106.6 KB	28.8 KB	11%	`app` Reference app	components `lib/hash` +0.9 KB `lib/heap` +0.5 KB `app (application code)` +0.2 KB / RAM +0.0 KB `lib/libc` +0.1 KB / RAM +0.0 KB `(merged strings)` +0.0 KB	ok
zcbor (CBOR encode/decode) `cat.lib.zcbor`	Libraries, ML & UI library	+1.6 KB	+0.0 KB	106.5 KB	28.7 KB	11%	`app` Reference app	components `modules/zcbor` +1.4 KB `app (application code)` +0.2 KB `(merged strings)` +0.0 KB `toolchain libs (libc, libgcc)` -0.0 KB `(linker fill)` +0.0 KB	ok
C++ RTTI `cat.lib.cpp_rtti`	Libraries, ML & UI library	+1.3 KB	+0.1 KB	108.9 KB	28.8 KB	11%	`cat.lib.libstdcpp` Full C++ standard library (libstdc++)	components `toolchain libs (libc, libgcc)` +0.9 KB `app (application code)` +0.3 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `arch (Cortex-M7)` +0.0 KB `lib/cpp` +0.0 KB / RAM +0.0 KB	ok
base64 encode/decode `cat.lib.base64`	Libraries, ML & UI library	+0.9 KB	+0.0 KB	105.7 KB	28.7 KB	11%	`app` Reference app	components `lib/utils` +0.7 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
LVGL extra widgets (chart, slider, dropdown, textarea, keyboard) `cat.ui.lvgl_widgets`	Libraries, ML & UI ui	+0.5 KB	+0.0 KB	317.7 KB	63.4 KB	25%	`cat.ui.lvgl` LVGL (label + button, 16 KB pool)	components `modules/lvgl` +0.3 KB `app (application code)` +0.2 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB	ok
Display API + dummy display controller `cat.ui.display_dummy`	Libraries, ML & UI driver	+0.4 KB	+0.1 KB	105.3 KB	28.8 KB	11%	`app` Reference app	zephyr,dummy-dc 320x240 node as zephyr,display; stands in for a real panel driver. components `drivers/display` +0.2 KB / RAM +0.0 KB `app (application code)` +0.1 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
CRC-32/16/8 `cat.lib.crc`	Libraries, ML & UI library	+0.4 KB	+0.0 KB	105.2 KB	28.7 KB	11%	`app` Reference app	components `subsys/crc` +0.2 KB `app (application code)` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Ring buffer `cat.lib.ring_buffer`	Libraries, ML & UI library	+0.1 KB	+0.1 KB	105.0 KB	28.8 KB	11%	`app` Reference app	components `app (application code)` +0.1 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB	ok
Newlib C library instead of picolibc `cat.lib.newlib`	Libraries, ML & UI library	–	–	–	–	–	`app` Reference app		not available: Zephyr SDK 1.0.1 ships only picolibc for arm-zephyr-eabi (no newlib libc.a/libc_nano.a), so NEWLIB_LIBC_SUPPORTED is n and CONFIG_NEWLIB_LIBC does not exist in the build. Use tune.minimal_libc for a libc comparison.
Rust application support `cat.lib.rust`	Libraries, ML & UI library	–	–	–	–	–	`app` Reference app		not available: No Rust toolchain (rustc/cargo with the thumbv7em target) in the Pixi environment or the Zephyr SDK, and the zephyr-lang-rust module is not in the workspace.
Bluetooth LE host + H:4 HCI over UART `cat.drv.bt_hci_uart`	Drivers & buses connectivity	+51.5 KB	+13.1 KB	156.4 KB	41.8 KB	16%	`app` Reference app	BLE host stack (peripheral role, GAP/GATT/SMP off) with the H:4 UART HCI driver on LPUART5. The controller runs on an external chip. Stub enables BT and starts advertising. Hardware: BLE controller with HCI UART firmware (nRF52840 dongle with hci_uart, or HCI-mode module) on pins 35/34 + RTS/CTS components `subsys/bluetooth` +29.5 KB / RAM +10.3 KB `modules/mbedtls` +13.1 KB / RAM +1.3 KB `(merged strings)` +4.9 KB `drivers/bluetooth` +1.6 KB / RAM +1.5 KB `modules/hal_nxp` +0.8 KB	ok
Sensor shell (sensor get) `cat.drv.sensor_shell`	Drivers & buses debug	+19.6 KB	+6.5 KB	128.7 KB	35.4 KB	14%	`cat.drv.sensor_bme280` BME280 environment sensor on I2C	Sensor shell. It turns on float printf (CBPRINTF_FP_SUPPORT) and the RTIO sensor read path with a work queue, so the delta is large. Hardware: BME280 breakout on pins 19/18 components `drivers/sensor` +7.6 KB / RAM +4.9 KB `toolchain libs (libc, libgcc)` +6.7 KB `(merged strings)` +3.1 KB `subsys/rtio` +1.4 KB / RAM +1.5 KB `lib/utils` +0.8 KB	ok
I2S audio (SAI1, eDMA) `cat.drv.i2s_sai`	Drivers & buses driver	+13.1 KB	+8.1 KB	118.0 KB	36.8 KB	14%	`app` Reference app	I2S subsystem and the MCUX SAI driver on sai1 with eDMA. Stub configures TX and writes one block. Hardware: I2S codec or DAC (e.g. PCM5102, SGTL5000 audio shield) on pins 23 (MCLK), 21 (BCLK), 20 (LRCLK), 7 (TX), 8 (RX) components `drivers/i2s` +4.5 KB / RAM +0.5 KB `modules/hal_nxp` +3.7 KB / RAM +0.1 KB `drivers/dma` +3.0 KB / RAM +6.7 KB `(merged strings)` +1.6 KB `app (application code)` +0.2 KB / RAM +0.8 KB	ok
External CAN controller MCP2515 on SPI `cat.drv.can_mcp2515`	Drivers & buses driver	+12.9 KB	+3.5 KB	121.6 KB	32.3 KB	13%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	MCP2515 driver on LPSPI3 CS 36. Parent has SPI only; the CAN subsystem is part of the delta. Compare with cat.drv.can for the on-chip FlexCAN. Hardware: MCP2515 + TJA1050/MCP2551 module, 16 MHz crystal; CS pin 36, INT pin 9 components `drivers/can` +8.2 KB / RAM +3.5 KB `modules/hal_nxp` +3.4 KB / RAM +0.0 KB `(merged strings)` +1.2 KB `drivers/clock_control` +0.1 KB `kernel` +0.0 KB	ok
LoRa radio SX1276 on SPI (point-to-point) `cat.drv.lora_sx1276`	Drivers & buses connectivity	+10.5 KB	+1.2 KB	119.2 KB	30.0 KB	12%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	LoRa subsystem and the SX127x driver (uses the loramac-node radio driver) on LPSPI3 CS 38. Hardware: RFM95W/SX1276 module on LPSPI3, CS pin 38, RESET pin 5, DIO0 pin 6, DIO1 pin 33, antenna components `drivers/lora` +8.9 KB / RAM +0.9 KB `kernel` +1.0 KB / RAM +0.0 KB `(merged strings)` +0.5 KB `drivers/usb` +0.1 KB / RAM +0.1 KB `subsys/usb` +0.0 KB / RAM +0.0 KB	ok
CAN shell (can start/send/dump) `cat.drv.can_shell`	Drivers & buses debug	+9.6 KB	+0.7 KB	122.9 KB	31.2 KB	12%	`cat.drv.can` CAN driver (FlexCAN1)	Hardware: CAN transceiver on pins 22/23 components `drivers/can` +4.9 KB / RAM +0.5 KB `(merged strings)` +3.4 KB `kernel` +1.1 KB / RAM +0.0 KB `drivers/usb` +0.1 KB / RAM +0.1 KB `subsys/usb` +0.0 KB / RAM +0.0 KB	ok
SPI + FlexSPI NOR flash driver (SPI shell prerequisite) `cat.drv.spi_flexspi`	Drivers & buses driver	+9.0 KB	+9.0 KB	117.8 KB	37.9 KB	15%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	Flash subsystem with the FlexSPI NOR driver for the boot flash. The SPI shell lists every node on an SPI-type bus, including the FlexSPI NOR node, so it links only when the FlexSPI controller device exists. Zephyr v4.4 limitation on this board. The FlexSPI NOR and FlexSPI HAL code runs from ITCM (XIP safety), so it counts in FLASH (load image) and in RAM. components `drivers/flash` +4.9 KB / RAM +5.1 KB `modules/hal_nxp` +2.7 KB / RAM +2.7 KB `drivers/memc` +1.1 KB / RAM +1.0 KB `SoC (i.MX RT)` +0.1 KB / RAM +0.1 KB `generated (ISR tables)` +0.1 KB / RAM +0.1 KB	ok
SD card over SPI (SDHC SPI host + SDMMC disk) `cat.drv.sd_spi`	Drivers & buses driver	+8.8 KB	+0.8 KB	117.5 KB	29.6 KB	12%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	SDHC-over-SPI host driver, SD stack and disk "SD" on LPSPI3 CS 38; the on-board uSDHC1 node is disabled. Compare with cat.store.sdmmc_disk (uSDHC, native 4-bit). Hardware: microSD SPI breakout on LPSPI3, CS pin 38 (the on-board slot is wired to uSDHC1 only) components `subsys/sd` +3.8 KB / RAM +0.0 KB `drivers/sdhc` +2.7 KB / RAM +0.1 KB `(merged strings)` +1.3 KB `subsys/disk` +0.5 KB / RAM +0.0 KB `drivers/disk` +0.2 KB / RAM +0.2 KB	ok
CAN driver (FlexCAN1) `cat.drv.can`	Drivers & buses driver	+8.4 KB	+1.8 KB	113.3 KB	30.5 KB	12%	`app` Reference app	CAN subsystem and the MCUX FlexCAN driver for flexcan1 (zephyr,canbus, enabled in the board DTS). The API struct keeps all driver functions, so no stub. Hardware: CAN transceiver (e.g. SN65HVD230, 3.3 V) on pins 22 (CTX1) / 23 (CRX1) components `drivers/can` +4.4 KB / RAM +1.8 KB `modules/hal_nxp` +3.4 KB / RAM +0.0 KB `(merged strings)` +0.6 KB `drivers/clock_control` +0.1 KB `SoC (i.MX RT)` +0.0 KB	ok
UART async API (eDMA) on LPUART2 `cat.drv.uart_async`	Drivers & buses driver	+8.2 KB	+5.3 KB	113.2 KB	34.0 KB	13%	`cat.drv.uart2` Extra UART instance (LPUART2, interrupt driven)	UART_ASYNC_API with the LPUART eDMA back end (dmas from the SoC DTS) and the eDMA driver. Hardware: 3.3 V UART on pins 14/15 components `drivers/dma` +3.0 KB / RAM +4.7 KB `drivers/serial` +2.1 KB / RAM +0.5 KB `modules/hal_nxp` +1.8 KB / RAM +0.1 KB `(merged strings)` +1.0 KB `kernel` +0.1 KB	ok
GNSS receiver (generic NMEA over UART) `cat.drv.gnss_nmea`	Drivers & buses driver	+6.0 KB	+1.3 KB	110.8 KB	30.0 KB	12%	`app` Reference app	GNSS subsystem, modem pipe/chat library and the generic NMEA0183 driver on LPUART5. A data callback is the API user. Hardware: GNSS module with NMEA output (u-blox NEO-M8N, Quectel L76) on pins 35 (TX8) / 34 (RX8), 9600 Bd components `subsys/modem` +3.5 KB / RAM +0.0 KB `drivers/gnss` +1.8 KB / RAM +1.3 KB `(merged strings)` +0.3 KB `kernel` +0.2 KB `drivers/serial` +0.2 KB / RAM +0.0 KB	ok
DMA API (eDMA, memory to memory) `cat.drv.dma`	Drivers & buses driver	+5.6 KB	+4.9 KB	110.5 KB	33.6 KB	13%	`app` Reference app	DMA subsystem and the MCUX eDMA driver for edma0 (enabled in the board DTS). Zephyr has no DMA shell; a stub uses the API. The driver keeps per-channel state for all 32 channels (about 4.8 KB RAM). components `drivers/dma` +3.0 KB / RAM +4.7 KB `modules/hal_nxp` +1.8 KB / RAM +0.1 KB `(merged strings)` +0.5 KB `app (application code)` +0.3 KB / RAM +0.1 KB `drivers/clock_control` +0.0 KB	ok
LPSPI eDMA transfers (instead of CPU) `cat.drv.spi_dma`	Drivers & buses driver	+5.3 KB	+4.9 KB	114.0 KB	33.8 KB	13%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	dmas on lpspi3 (eDMA channels 2/3, mux 15/16 as on the MIMXRT1060-EVK) select the DMA variant of the LPSPI driver and the eDMA driver. Hardware: SPI device on LPSPI3 components `drivers/dma` +3.0 KB / RAM +4.7 KB `modules/hal_nxp` +1.8 KB / RAM +0.1 KB `(merged strings)` +0.6 KB `drivers/spi` -0.1 KB / RAM +0.1 KB `drivers/clock_control` +0.0 KB	ok
Stepper motion controller (GPIO step/dir) `cat.drv.stepper_step_dir`	Drivers & buses driver	+5.2 KB	+0.2 KB	110.0 KB	29.0 KB	11%	`app` Reference app	Stepper subsystem and the GPIO step/dir motion controller (work-queue timing, no counter). Hardware: step/dir driver (A4988, DRV8825, TMC2209 standalone) STEP pin 2, DIR pin 3 components `drivers/stepper` +2.2 KB / RAM +0.2 KB `drivers/counter` +1.5 KB / RAM +0.1 KB `(merged strings)` +0.8 KB `modules/hal_nxp` +0.4 KB `kernel` +0.2 KB	ok
FlexIO SPI controller (FlexIO2) `cat.drv.spi_flexio`	Drivers & buses driver	+4.6 KB	+0.2 KB	113.3 KB	29.1 KB	11%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	Second SPI bus emulated by FlexIO2 (MCUX FlexIO core + FlexIO SPI driver); parent already has the SPI subsystem. Hardware: FlexIO2 pins 6 (SDO, FLEXIO2_10), 9 (SDI, FLEXIO2_11), 32 (SCK, FLEXIO2_12), CS pin 10 components `drivers/spi` +2.1 KB / RAM +0.2 KB `modules/hal_nxp` +1.5 KB / RAM +0.0 KB `drivers/misc` +0.6 KB / RAM +0.1 KB `(merged strings)` +0.2 KB `SoC (i.MX RT)` +0.1 KB	ok
Flash shell on SPI NOR `cat.drv.spi_nor_shell`	Drivers & buses debug	+4.4 KB	+8.3 KB	114.5 KB	37.1 KB	15%	`cat.drv.spi_nor` External SPI NOR flash (second chip select)	Flash shell (about 8 KB RAM of test/IO buffers at default sizes). Its default device is chosen zephyr,flash-controller; the overlay points it at the SPI NOR, because the FlexSPI NOR driver is off in the parent. Hardware: W25Q128 on LPSPI3, CS pin 36 components `drivers/flash` +2.7 KB / RAM +8.3 KB `(merged strings)` +1.7 KB `subsys/shell` +0.0 KB	ok
Regulator shell `cat.drv.regulator_shell`	Drivers & buses debug	+4.3 KB	+0.0 KB	110.3 KB	28.7 KB	11%	`cat.drv.regulator_fixed` Regulator API (regulator-fixed with enable GPIO)	components `drivers/regulator` +2.7 KB `(merged strings)` +1.6 KB `subsys/shell` +0.0 KB `(linker fill)` +0.0 KB	ok
Stepper shell `cat.drv.stepper_shell`	Drivers & buses debug	+4.3 KB	+0.0 KB	114.3 KB	29.0 KB	11%	`cat.drv.stepper_step_dir` Stepper motion controller (GPIO step/dir)	components `drivers/stepper` +2.7 KB / RAM +0.0 KB `(merged strings)` +1.4 KB `subsys/shell` +0.2 KB `(linker fill)` -0.0 KB	ok
On-die temperature monitor (TEMPMON) sensor `cat.drv.tempmon`	Drivers & buses driver	+4.2 KB	+0.0 KB	109.0 KB	28.7 KB	11%	`app` Reference app	NXP TEMPMON driver with the sensor API. No external hardware. The driver uses float math; the app builds without FPU (CONFIG_FPU=n), so about 3.8 KB of the delta is libgcc soft-float. components `toolchain libs (libc, libgcc)` +3.7 KB `drivers/sensor` +0.4 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
LoRa shell `cat.drv.lora_shell`	Drivers & buses debug	+4.1 KB	+0.2 KB	123.3 KB	30.3 KB	12%	`cat.drv.lora_sx1276` LoRa radio SX1276 on SPI (point-to-point)	components `zephyr-core` +7.6 KB / RAM +0.3 KB `subsys/shell` -4.3 KB `(merged strings)` +0.8 KB `(linker fill)` -0.0 KB	ok
SPI driver (LPSPI3, CPU mode) `cat.drv.spi`	Drivers & buses driver	+3.9 KB	+0.1 KB	108.7 KB	28.8 KB	11%	`app` Reference app	SPI subsystem and the NXP LPSPI driver for lpspi3 (enabled in teensy41.dts), interrupt/CPU transfers. The overlay adds three GPIO chip selects for the SPI device variants. Hardware: SPI devices on pins 39 (MISO), 26 (MOSI), 27 (SCK); CS 38, 36, 37 components `drivers/spi` +3.5 KB / RAM +0.1 KB `(merged strings)` +0.3 KB `drivers/clock_control` +0.0 KB `SoC (i.MX RT)` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
CAN FD mode + FlexCAN3 (CAN FD controller) `cat.drv.canfd`	Drivers & buses driver	+3.5 KB	+1.7 KB	116.8 KB	32.2 KB	13%	`cat.drv.can` CAN driver (FlexCAN1)	CAN_FD_MODE=y and a second instance, flexcan3 (nxp,flexcan-fd), as zephyr,canbus. Delta = FD code paths in the driver and core + one more controller instance. Hardware: CAN FD transceiver (e.g. TCAN337, MCP2562FD) on pins 31 (CTX3) / 30 (CRX3) components `drivers/can` +2.5 KB / RAM +1.7 KB `modules/hal_nxp` +0.8 KB `(merged strings)` +0.2 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
LED shell `cat.drv.led_shell`	Drivers & buses debug	+3.2 KB	+0.0 KB	108.7 KB	28.7 KB	11%	`cat.drv.led_gpio` LED API (gpio-leds driver)	components `drivers/led` +1.9 KB / RAM +0.0 KB `(merged strings)` +1.3 KB `subsys/shell` +0.0 KB	ok
1-Wire over UART + DS18B20 temperature sensor `cat.drv.w1_ds18b20`	Drivers & buses driver	+2.9 KB	+0.1 KB	107.8 KB	28.8 KB	11%	`app` Reference app	W1 serial master on LPUART4 (half duplex, TX/RX joined) and the DS18B20 sensor driver with the sensor API. Hardware: DS18B20 on pins 8 (TX2) and 7 (RX2) joined with a diode/open-drain buffer, 4.7 kOhm pull-up components `drivers/w1` +1.5 KB / RAM +0.0 KB `drivers/sensor` +0.9 KB / RAM +0.0 KB `(merged strings)` +0.3 KB `drivers/serial` +0.2 KB / RAM +0.0 KB `subsys/crc` +0.1 KB	ok
ADC shell `cat.drv.adc_shell`	Drivers & buses debug	+2.9 KB	+0.1 KB	109.6 KB	29.0 KB	11%	`cat.drv.adc` ADC driver (ADC1, 12-bit SAR)	Hardware: analog inputs on pins 14/15 components `drivers/adc` +2.0 KB / RAM +0.1 KB `(merged strings)` +0.9 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
SPI shell `cat.drv.spi_shell`	Drivers & buses debug	+2.8 KB	+0.8 KB	120.6 KB	38.6 KB	15%	`cat.drv.spi_flexspi` SPI + FlexSPI NOR flash driver (SPI shell prerequisite)	Hardware: SPI device on LPSPI3 components `drivers/spi` +1.9 KB / RAM +0.7 KB `(merged strings)` +0.8 KB `subsys/shell` +0.1 KB `(linker fill)` +0.0 KB	ok
SSD1306 OLED display driver (I2C) `cat.drv.display_ssd1306`	Drivers & buses driver	+2.8 KB	+0.1 KB	110.4 KB	28.9 KB	11%	`cat.drv.i2c` I2C driver (LPI2C1)	Display subsystem and the SSD1306 driver, 128x64 at 0x3c. Stub writes one block. LVGL is in the UI catalogue. Hardware: 0.96 inch SSD1306 128x64 OLED on pins 19/18, address 0x3c components `drivers/display` +2.0 KB / RAM +0.0 KB `(merged strings)` +0.7 KB `app (application code)` +0.1 KB / RAM +0.1 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
I2C driver (LPI2C1) `cat.drv.i2c`	Drivers & buses driver	+2.8 KB	+0.1 KB	107.6 KB	28.8 KB	11%	`app` Reference app	I2C subsystem and the MCUX LPI2C driver for lpi2c1 (pinctrl from the board DTS), 100 kHz. Hardware: I2C devices on pins 19 (SCL) / 18 (SDA) with 2.2-4.7 kOhm pull-ups to 3.3 V components `modules/hal_nxp` +1.7 KB / RAM +0.0 KB `drivers/i2c` +0.9 KB / RAM +0.1 KB `(merged strings)` +0.1 KB `drivers/clock_control` +0.1 KB `SoC (i.MX RT)` +0.0 KB	ok
ILI9341 TFT display driver (MIPI DBI over SPI) `cat.drv.display_ili9341`	Drivers & buses driver	+2.7 KB	+0.1 KB	111.4 KB	29.0 KB	11%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	Display subsystem, MIPI DBI SPI adapter and the ILI9341 driver, 320x240 RGB565. Stub writes one block. LVGL is in the UI catalogue. Hardware: 2.8 inch ILI9341 SPI TFT on LPSPI3, CS pin 37, D/C pin 40, RESET pin 41 components `drivers/display` +1.5 KB / RAM +0.0 KB `drivers/mipi_dbi` +0.6 KB / RAM +0.0 KB `(merged strings)` +0.4 KB `app (application code)` +0.1 KB / RAM +0.1 KB `(linker fill)` +0.0 KB	ok
Quadrature decoder (ENC1 via XBAR) `cat.drv.qdec`	Drivers & buses driver	+2.7 KB	+0.1 KB	107.5 KB	28.8 KB	11%	`app` Reference app	MCUX QDEC (ENC1) sensor driver with the XBAR1 input routing; sensor API. Hardware: quadrature encoder A/B on pins 2/3 (XBAR1_INOUT06/07) components `toolchain libs (libc, libgcc)` +1.5 KB `drivers/sensor` +0.6 KB / RAM +0.0 KB `modules/hal_nxp` +0.5 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
I2C shell (i2c scan/read/write) `cat.drv.i2c_shell`	Drivers & buses debug	+2.3 KB	+0.0 KB	110.0 KB	28.8 KB	11%	`cat.drv.i2c` I2C driver (LPI2C1)	Hardware: I2C devices on pins 19/18 components `drivers/i2c` +1.5 KB / RAM +0.0 KB `(merged strings)` +0.8 KB `subsys/shell` +0.1 KB `(linker fill)` +0.0 KB	ok
PWM driver (FlexPWM2 submodule 0) `cat.drv.pwm`	Drivers & buses driver	+2.3 KB	+0.1 KB	107.2 KB	28.8 KB	11%	`app` Reference app	PWM subsystem and the MCUX FlexPWM driver for flexpwm2_pwm0 (PWMA0 on pin 4). Hardware: PWM output on pin 4 components `modules/hal_nxp` +1.1 KB / RAM +0.0 KB `drivers/pwm` +1.0 KB / RAM +0.1 KB `(merged strings)` +0.2 KB `drivers/clock_control` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
GPIO keyboard matrix (4x4) `cat.drv.input_kbd_matrix`	Drivers & buses driver	+2.2 KB	+1.6 KB	108.4 KB	31.9 KB	12%	`cat.drv.input_gpio_keys` Input subsystem + gpio-keys (2 buttons)	GPIO keyboard-matrix driver with the input keymap scan thread, 4 rows x 4 columns. Hardware: 4x4 membrane keypad, rows on pins 4, 33, 5, 6; columns on pins 9, 10, 40, 41 components `drivers/input` +2.1 KB / RAM +1.6 KB `(merged strings)` +0.1 KB `kernel` +0.0 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
Counter driver (GPT2 + SNVS RTC counter) `cat.drv.counter`	Drivers & buses driver	+2.1 KB	+0.1 KB	106.9 KB	28.8 KB	11%	`app` Reference app	Counter subsystem. gpt2 and the SNVS RTC counter have no status "disabled" in the SoC DTS, so COUNTER=y builds both instances. components `drivers/counter` +1.5 KB / RAM +0.1 KB `modules/hal_nxp` +0.4 KB `(merged strings)` +0.2 KB `drivers/clock_control` +0.0 KB `(linker fill)` +0.0 KB	ok
UART shell (uart write/read/baudrate) `cat.drv.uart_shell`	Drivers & buses debug	+2.0 KB	+0.0 KB	107.1 KB	28.7 KB	11%	`cat.drv.uart2` Extra UART instance (LPUART2, interrupt driven)	components `drivers/serial` +1.3 KB / RAM +0.0 KB `(merged strings)` +0.7 KB `subsys/shell` +0.0 KB `(linker fill)` -0.0 KB	ok
FlexIO PWM (FlexIO1) `cat.drv.pwm_flexio`	Drivers & buses driver	+2.0 KB	+0.1 KB	109.2 KB	28.9 KB	11%	`cat.drv.pwm` PWM driver (FlexPWM2 submodule 0)	PWM channel emulated by FlexIO1 timer (MCUX FlexIO core + FlexIO PWM driver); parent already has the PWM subsystem. Hardware: PWM output on pin 2 (FLEXIO1_04) components `drivers/pwm` +0.8 KB / RAM +0.0 KB `drivers/misc` +0.5 KB / RAM +0.1 KB `modules/hal_nxp` +0.3 KB `(merged strings)` +0.2 KB `drivers/clock_control` +0.1 KB	ok
ADC driver (ADC1, 12-bit SAR) `cat.drv.adc`	Drivers & buses driver	+1.8 KB	+0.2 KB	106.7 KB	28.9 KB	11%	`app` Reference app	ADC subsystem and the MCUX 12B1MSPS SAR driver for adc1, inputs A0 (ADC1_IN7) and A1 (ADC1_IN8). Hardware: analog inputs on pins 14 (A0) / 15 (A1), 0-3.3 V components `drivers/adc` +1.2 KB / RAM +0.2 KB `modules/hal_nxp` +0.4 KB `(merged strings)` +0.2 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
LED strip shell `cat.drv.led_strip_shell`	Drivers & buses debug	+1.6 KB	+0.0 KB	111.0 KB	29.2 KB	11%	`cat.drv.led_strip_ws2812` WS2812 LED strip over SPI	components `drivers/led_strip` +0.8 KB / RAM +0.0 KB `(merged strings)` +0.6 KB `lib/utils` +0.2 KB `subsys/shell` +0.0 KB `(linker fill)` +0.0 KB	ok
Counter shell `cat.drv.counter_shell`	Drivers & buses debug	+1.6 KB	+0.0 KB	108.5 KB	28.8 KB	11%	`cat.drv.counter` Counter driver (GPT2 + SNVS RTC counter)	components `drivers/counter` +0.9 KB / RAM +0.0 KB `(merged strings)` +0.6 KB `subsys/shell` +0.0 KB `(linker fill)` -0.0 KB	ok
Counter on QuadTimer (QTMR1 channel 0) `cat.drv.counter_qtmr`	Drivers & buses driver	+1.5 KB	+0.1 KB	108.4 KB	28.8 KB	11%	`cat.drv.counter` Counter driver (GPT2 + SNVS RTC counter)	components `drivers/counter` +1.0 KB / RAM +0.0 KB `modules/hal_nxp` +0.5 KB `(merged strings)` +0.0 KB `drivers/clock_control` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
EEPROM shell `cat.drv.eeprom_shell`	Drivers & buses debug	+1.5 KB	+0.0 KB	110.3 KB	28.8 KB	11%	`cat.drv.eeprom_at24` I2C EEPROM (AT24C256)	Hardware: AT24C256 on pins 19/18 components `drivers/eeprom` +1.0 KB `(merged strings)` +0.5 KB `subsys/shell` +0.0 KB `(linker fill)` +0.0 KB	ok
BME280 environment sensor on I2C `cat.drv.sensor_bme280`	Drivers & buses driver	+1.5 KB	+0.1 KB	109.1 KB	28.9 KB	11%	`cat.drv.i2c` I2C driver (LPI2C1)	Sensor subsystem and the Bosch BME280 driver at 0x76 on lpi2c1. Hardware: BME280 breakout on pins 19/18, address 0x76 components `drivers/sensor` +1.5 KB / RAM +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
External SPI NOR flash (second chip select) `cat.drv.spi_nor`	Drivers & buses driver	+1.4 KB	+0.0 KB	110.1 KB	28.8 KB	11%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	Flash subsystem and the generic jedec,spi-nor driver (SFDP from DT size) on CS 36. The FlexSPI NOR flash driver for the boot flash is switched off, so the delta is the SPI NOR path only. Hardware: W25Q128 SPI NOR on LPSPI3, CS pin 36 components `drivers/flash` +1.4 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
PWM shell `cat.drv.pwm_shell`	Drivers & buses debug	+1.3 KB	+0.0 KB	108.5 KB	28.8 KB	11%	`cat.drv.pwm` PWM driver (FlexPWM2 submodule 0)	Hardware: PWM output on pin 4 components `drivers/pwm` +0.9 KB `(merged strings)` +0.4 KB `subsys/shell` +0.0 KB	ok
Input subsystem + gpio-keys (2 buttons) `cat.drv.input_gpio_keys`	Drivers & buses driver	+1.3 KB	+1.6 KB	106.1 KB	30.3 KB	12%	`app` Reference app	Input subsystem (thread mode) and the gpio-keys driver with two buttons and debounce. Hardware: push buttons to GND on pins 2 and 3 components `drivers/input` +0.7 KB / RAM +0.1 KB `subsys/input` +0.3 KB / RAM +1.5 KB `(merged strings)` +0.2 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
I2C EEPROM (AT24C256) `cat.drv.eeprom_at24`	Drivers & buses driver	+1.2 KB	+0.0 KB	108.8 KB	28.8 KB	11%	`cat.drv.i2c` I2C driver (LPI2C1)	EEPROM subsystem and the AT24 driver, 32 KiB device at 0x50. Hardware: 24LC256/AT24C256 on pins 19/18, address 0x50 components `drivers/eeprom` +1.0 KB / RAM +0.0 KB `(merged strings)` +0.2 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
Hardware watchdog (WDOG1) `cat.drv.wdt`	Drivers & buses driver	+1.1 KB	+0.0 KB	106.0 KB	28.7 KB	11%	`app` Reference app	Watchdog subsystem and the MCUX i.MX WDOG driver for wdog0. Once started, WDOG cannot be stopped. components `drivers/watchdog` +0.5 KB / RAM +0.0 KB `modules/hal_nxp` +0.3 KB `(merged strings)` +0.2 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
Regulator API (regulator-fixed with enable GPIO) `cat.drv.regulator_fixed`	Drivers & buses driver	+1.1 KB	+0.0 KB	105.9 KB	28.7 KB	11%	`app` Reference app	Regulator subsystem and the fixed regulator driver (load switch with enable GPIO). Hardware: load switch / LDO enable on pin 5 components `drivers/regulator` +1.0 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
Entropy driver (TRNG) `cat.drv.entropy`	Drivers & buses driver	+1.1 KB	+0.0 KB	105.9 KB	28.7 KB	11%	`app` Reference app	Entropy subsystem and the MCUX TRNG driver. Zephyr has no entropy shell; a stub reads 16 bytes. components `modules/hal_nxp` +0.8 KB `drivers/entropy` +0.1 KB / RAM +0.0 KB `app (application code)` +0.1 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
RTC shell (rtc get/set) `cat.drv.rtc_shell`	Drivers & buses debug	+1.0 KB	+0.0 KB	108.7 KB	28.8 KB	11%	`cat.drv.rtc` RTC API (rtc-counter on SNVS)	components `drivers/rtc` +0.8 KB `(merged strings)` +0.2 KB `subsys/shell` +0.0 KB `toolchain libs (libc, libgcc)` +0.0 KB `(linker fill)` -0.0 KB	ok
Counter on PIT channel 0 `cat.drv.counter_pit`	Drivers & buses driver	+1.0 KB	+0.0 KB	108.0 KB	28.8 KB	11%	`cat.drv.counter` Counter driver (GPT2 + SNVS RTC counter)	components `drivers/counter` +0.8 KB / RAM +0.0 KB `(merged strings)` +0.1 KB `modules/hal_nxp` +0.1 KB `drivers/clock_control` +0.0 KB `(linker fill)` -0.0 KB	ok
Watchdog shell `cat.drv.wdt_shell`	Drivers & buses debug	+1.0 KB	+0.0 KB	106.9 KB	28.7 KB	11%	`cat.drv.wdt` Hardware watchdog (WDOG1)	components `drivers/watchdog` +0.6 KB `(merged strings)` +0.3 KB `subsys/shell` +0.0 KB `(linker fill)` +0.0 KB	ok
I2C target (slave) mode API `cat.drv.i2c_target`	Drivers & buses driver	+0.7 KB	+0.1 KB	108.4 KB	28.9 KB	11%	`cat.drv.i2c` I2C driver (LPI2C1)	I2C_TARGET=y adds the LPI2C target-mode code paths. components `drivers/i2c` +0.4 KB / RAM +0.0 KB `modules/hal_nxp` +0.3 KB	ok
RTC API (rtc-counter on SNVS) `cat.drv.rtc`	Drivers & buses driver	+0.7 KB	+0.0 KB	107.7 KB	28.8 KB	11%	`cat.drv.counter` Counter driver (GPT2 + SNVS RTC counter)	RTC subsystem through the zephyr,rtc-counter adapter on the SNVS RTC counter. RTC_INIT_PRIORITY is raised above the counter priority (build assert). Battery-backed time needs VBAT. Hardware: optional coin cell on the VBAT pad for retention components `drivers/rtc` +0.6 KB / RAM +0.0 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
SHT3x humidity sensor on I2C `cat.drv.sensor_sht3x`	Drivers & buses driver	+0.6 KB	+0.0 KB	108.3 KB	28.8 KB	11%	`cat.drv.i2c` I2C driver (LPI2C1)	Sensor subsystem and the Sensirion SHT3xD driver at 0x44 on lpi2c1. Hardware: SHT31 breakout on pins 19/18, address 0x44 components `drivers/sensor` +0.5 KB / RAM +0.0 KB `subsys/crc` +0.1 KB `(merged strings)` +0.0 KB `(linker fill)` +0.0 KB / RAM +0.0 KB	ok
WS2812 LED strip over SPI `cat.drv.led_strip_ws2812`	Drivers & buses driver	+0.6 KB	+0.4 KB	109.4 KB	29.2 KB	11%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	LED strip subsystem and the WS2812-over-SPI driver, 16 LEDs (SPI MOSI generates the bit timing). Hardware: WS2812B strip data on pin 26 (LPSPI3 MOSI) via a 3.3->5 V level shifter; bus not shared in practice components `drivers/led_strip` +0.5 KB / RAM +0.4 KB `(merged strings)` +0.1 KB `kernel` +0.0 KB `(linker fill)` -0.0 KB / RAM +0.0 KB	ok
LED API (gpio-leds driver) `cat.drv.led_gpio`	Drivers & buses driver	+0.6 KB	+0.0 KB	105.4 KB	28.7 KB	11%	`app` Reference app	LED subsystem and the gpio-leds driver for the board LED (pin 13). The app drives the LED with the GPIO API instead. components `drivers/led` +0.5 KB / RAM +0.0 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
SPI asynchronous API `cat.drv.spi_async`	Drivers & buses driver	+0.5 KB	+0.3 KB	109.3 KB	29.1 KB	11%	`cat.drv.spi` SPI driver (LPSPI3, CPU mode)	components `kernel` +0.3 KB / RAM +0.0 KB `drivers/spi` +0.1 KB / RAM +0.0 KB `drivers/usb` +0.1 KB / RAM +0.1 KB `subsys/usb` +0.0 KB / RAM +0.0 KB `subsys/logging` +0.0 KB / RAM +0.0 KB	ok
Input shell (input dump) `cat.drv.input_shell`	Drivers & buses debug	+0.5 KB	+0.0 KB	106.7 KB	30.3 KB	12%	`cat.drv.input_gpio_keys` Input subsystem + gpio-keys (2 buttons)	Hardware: push buttons on pins 2 and 3 components `subsys/input` +0.3 KB `(merged strings)` +0.1 KB `subsys/shell` +0.1 KB `(linker fill)` +0.0 KB	ok
Extra UART instance (LPUART2, interrupt driven) `cat.drv.uart2`	Drivers & buses driver	+0.2 KB	+0.0 KB	105.0 KB	28.7 KB	11%	`app` Reference app	One more LPUART instance. The UART driver is already in the app (board LPUART6), so this is the cost of one instance. Hardware: 3.3 V UART on pins 14 (TX3) / 15 (RX3) components `drivers/serial` +0.2 KB / RAM +0.0 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
RS-485 with hardware DE (LPUART2 RTS) `cat.drv.rs485_hw`	Drivers & buses driver	+0.0 KB	+0.0 KB	105.1 KB	28.7 KB	11%	`cat.drv.uart2` Extra UART instance (LPUART2, interrupt driven)	nxp,rs485-mode lets the LPUART drive the transceiver DE pin from its RTS output. Only a DT/driver flag; Modbus below uses de-gpios instead. Hardware: RS-485 transceiver (e.g. MAX3485, THVD1450) on pins 14/15, DE/nRE on pin 18 (LPUART2_RTS, conflicts with LPI2C1 SDA) components `drivers/serial` +0.0 KB	ok
Bluetooth (on-chip radio) `cat.drv.bt_native`	Drivers & buses connectivity	–	–	–	–	–	`app` Reference app		not available: i.MX RT1062 has no radio. Use cat.drv.bt_hci_uart with an external controller.
Wi-Fi (on-chip radio) `cat.drv.wifi_native`	Drivers & buses connectivity	–	–	–	–	–	`app` Reference app		not available: i.MX RT1062 has no radio. An external ESP32 with ESP-AT firmware over UART (drivers/wifi/esp_at) needs the network stack; it belongs in the networking catalogue.
USB host stack + shell (USB2 host port, EHCI) `cat.usb.host`	USB classes usb-class	+25.1 KB	+73.2 KB	130.0 KB	101.9 KB	40%	`app` Reference app	Experimental USB host stack on the second controller (usbh2, nxp,uhc-ehci) with the usbh shell, which defines the host context and drives enumeration. No host class drivers. The MCUX EHCI host keeps about 40 KB of controller structures, plus about 19 KB alignment fill in RAM. Hardware: Teensy 4.1 USB host pads (5 V, D+, D-, GND) with a USB-A host cable components `modules/hal_nxp` +9.1 KB / RAM +20.0 KB `subsys/usb` +8.4 KB / RAM +7.4 KB `(merged strings)` +4.3 KB `drivers/usb` +3.0 KB / RAM +21.6 KB `lib/utils` +0.1 KB	ok
USB Mass Storage (BOT) with 32 KiB RAM disk `cat.usb.msc`	USB classes usb-class	+20.6 KB	+34.8 KB	125.3 KB	63.5 KB	25%	`cat.usb.composite` App-owned USB device context (composite base)	MSC class, SCSI layer, disk access and a zephyr,ram-disk of 64 x 512 B (32 KiB RAM). The RAM disk dominates the RAM delta. components `subsys/sd` +5.2 KB / RAM +0.0 KB `subsys/usb` +5.0 KB / RAM +2.8 KB `drivers/sdhc` +4.3 KB / RAM +0.4 KB `modules/hal_nxp` +2.6 KB / RAM +0.0 KB `(merged strings)` +2.2 KB	ok
USB device shell (usbd ...) `cat.usb.shell`	USB classes debug	+7.4 KB	+0.4 KB	112.3 KB	29.1 KB	11%	`app` Reference app	USBD shell; it defines its own device context for interactive use. components `subsys/usb` +4.6 KB / RAM +0.4 KB `(merged strings)` +2.8 KB `drivers/usb` +0.1 KB `(linker fill)` -0.0 KB	ok
USB CDC-NCM Ethernet (with IPv4, next to ENET) `cat.usb.cdc_ncm`	USB classes usb-class	+4.8 KB	+10.3 KB	135.6 KB	70.9 KB	28%	`cat.net.ipv4` Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP)	CDC-NCM virtual Ethernet interface on top of the IPv4 stack, with the composite context stub. NCM works on Linux, macOS and Windows 10+. components `subsys/usb` +3.2 KB / RAM +4.3 KB `(merged strings)` +0.7 KB `app (application code)` +0.6 KB / RAM +0.4 KB `subsys/net` +0.2 KB / RAM +1.6 KB `(linker fill)` -0.0 KB / RAM +4.0 KB	ok
USB CDC-ECM Ethernet (with IPv4, next to ENET) `cat.usb.cdc_ecm`	USB classes usb-class	+3.6 KB	+10.2 KB	134.4 KB	70.9 KB	28%	`cat.net.ipv4` Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP)	CDC-ECM virtual Ethernet interface on top of the IPv4 stack, with the composite context stub. Parent is the networking IPv4 base, so the delta is the class + second interface + context. Linux and macOS support ECM natively, Windows does not. components `subsys/usb` +2.2 KB / RAM +3.2 KB `app (application code)` +0.6 KB / RAM +0.4 KB `(merged strings)` +0.6 KB `subsys/net` +0.2 KB / RAM +1.6 KB `lib/net_buf` +0.0 KB	ok
USB Audio Class 2 (stereo 48 kHz headphones) `cat.usb.uac2`	USB classes usb-class	+3.4 KB	+1.4 KB	108.2 KB	30.1 KB	12%	`cat.usb.composite` App-owned USB device context (composite base)	UAC2 class with one isochronous OUT stream (16-bit stereo, 48 kHz), as in samples/subsys/usb/uac2_explicit_feedback. Audio buffers in a small stub slab. components `subsys/usb` +2.8 KB / RAM +0.6 KB `(merged strings)` +0.3 KB `app (application code)` +0.2 KB / RAM +0.8 KB `lib/net_buf` +0.1 KB `drivers/usb` +0.0 KB	ok
USB HID keyboard `cat.usb.hid_kbd`	USB classes usb-class	+2.4 KB	+0.4 KB	107.1 KB	29.1 KB	11%	`cat.usb.composite` App-owned USB device context (composite base)	HID class with one boot keyboard instance (64 B IN report, 1 ms polling). components `subsys/usb` +1.8 KB / RAM +0.4 KB `(merged strings)` +0.3 KB `app (application code)` +0.2 KB / RAM +0.0 KB `lib/net_buf` +0.0 KB `(linker fill)` -0.0 KB / RAM -0.0 KB	ok
USB DFU (runtime + DFU mode, RAM image) `cat.usb.dfu`	USB classes usb-class	+2.1 KB	+4.4 KB	106.9 KB	33.1 KB	13%	`cat.usb.composite` App-owned USB device context (composite base)	DFU runtime interface in the composite device plus the DFU-mode class (blocklisted in the composite; needs its own context after detach) with one 4 KiB RAM image. The flash back end (USBD_DFU_FLASH) needs MCUboot slot partitions and is not measured. components `subsys/usb` +1.9 KB / RAM +0.4 KB `app (application code)` +0.1 KB / RAM +4.0 KB `(merged strings)` +0.1 KB `(linker fill)` -0.0 KB	ok
Second CDC-ACM serial port `cat.usb.cdc_acm2`	USB classes usb-class	+0.5 KB	+2.5 KB	105.3 KB	31.2 KB	12%	`cat.usb.composite` App-owned USB device context (composite base)	Second zephyr,cdc-acm-uart instance (UART device + 2 bulk + 1 interrupt endpoint, ring buffers). The FLASH region total drops here although the object sizes grow by about 540 B (layout/alignment effect); see the per-object attribution. components `subsys/usb` +0.5 KB / RAM +3.5 KB `(merged strings)` +0.0 KB `(linker fill)` -0.0 KB / RAM -1.0 KB	ok
App-owned USB device context (composite base) `cat.usb.composite`	USB classes usb-class	-0.1 KB	+0.0 KB	104.7 KB	28.7 KB	11%	`app` Reference app	Replaces CDC_ACM_SERIAL_INITIALIZE_AT_BOOT (one fixed CDC-ACM) by an application context that registers every enabled class (stub usbd_composite.c, after samples/subsys/usb/common). Console stays on cdc_acm_uart0. Base for all USB class variants. Hardware: USB device port (micro-USB) components `subsys/usb` -0.6 KB / RAM -0.4 KB `app (application code)` +0.6 KB / RAM +0.4 KB `(merged strings)` -0.1 KB `(linker fill)` +0.0 KB	ok
USB CDC-NCM as the only network interface (ENET off) `cat.usb.cdc_ncm_only`	USB classes usb-class	-4.9 KB	-6.3 KB	125.9 KB	54.4 KB	21%	`cat.net.ipv4` Ethernet + IPv4 + UDP (ARP, ICMPv4; no TCP)	Network over USB without the Ethernet magjack. ENET MAC, MDIO and PHY nodes are disabled; NCM is the only interface. Delta against cat.net.ipv4 = NCM + context - ENET driver. Hardware: USB device port only; no Ethernet kit needed components `drivers/ethernet` -5.0 KB / RAM -15.9 KB `modules/hal_nxp` -3.4 KB / RAM -0.1 KB `subsys/usb` +3.2 KB / RAM +4.3 KB `app (application code)` +0.6 KB / RAM +0.4 KB `(merged strings)` -0.1 KB	ok
LoRaWAN (loramac-node, EU868, OTAA) `cat.ind.lorawan`	Industrial & field protocol	+29.9 KB	+4.4 KB	149.1 KB	34.5 KB	13%	`cat.drv.lora_sx1276` LoRa radio SX1276 on SPI (point-to-point)	LoRaWAN MAC from loramac-node with the software secure element (AES/CMAC), region EU868, OTAA join and confirmed uplink. The soft SE needs a 2 KiB system work queue stack (default 1 KiB); this is in the RAM delta. Hardware: RFM95W/SX1276 module as above, LoRaWAN gateway coverage components `subsys/lorawan` +36.9 KB / RAM +4.3 KB `drivers/lora` -8.9 KB / RAM -0.9 KB `(merged strings)` +1.1 KB `toolchain libs (libc, libgcc)` +0.7 KB `app (application code)` +0.1 KB / RAM +0.0 KB	ok
CANopenNode (CiA 301) stack `cat.ind.canopen`	Industrial & field industrial	+17.2 KB	+4.6 KB	130.5 KB	35.1 KB	14%	`cat.drv.can` CAN driver (FlexCAN1)	CANopenNode with the object dictionary from the Zephyr sample (study/stubs/periph/canopen/CO_OD.c), NMT, SDO server, PDO, SYNC, EMCY, heartbeat, LED state machine. No OD storage (needs SETTINGS), no program download. Hardware: CAN transceiver on pins 22/23 components `modules/canopennode` +13.6 KB / RAM +3.9 KB `app (application code)` +2.2 KB / RAM +0.6 KB `(merged strings)` +0.8 KB `drivers/can` +0.5 KB `subsys/crc` +0.0 KB	ok
ISO-TP (ISO 15765-2) transport over CAN `cat.ind.isotp`	Industrial & field industrial	+6.8 KB	+1.9 KB	120.1 KB	32.5 KB	13%	`cat.drv.can` CAN driver (FlexCAN1)	ISO-TP bind/send/recv on flexcan1, used by UDS diagnostics. Default buffer pools. Hardware: CAN transceiver on pins 22/23 components `subsys/canbus` +4.7 KB / RAM +1.3 KB `(merged strings)` +0.9 KB `drivers/can` +0.4 KB / RAM +0.0 KB `kernel` +0.4 KB / RAM +0.0 KB `app (application code)` +0.2 KB / RAM +0.4 KB	ok
Modbus RTU server (RS-485, DE GPIO) `cat.ind.modbus_rtu_server`	Industrial & field industrial	+6.3 KB	+1.1 KB	111.3 KB	29.8 KB	12%	`cat.drv.uart2` Extra UART instance (LPUART2, interrupt driven)	Modbus serial RTU server (unit 1) on LPUART2 with holding-register callbacks. Hardware: RS-485 transceiver on pins 14/15, DE pin 2, nRE pin 3 components `subsys/modbus` +5.0 KB / RAM +1.0 KB `(merged strings)` +1.1 KB `app (application code)` +0.2 KB / RAM +0.1 KB `subsys/crc` +0.0 KB `(linker fill)` -0.0 KB	ok
Modbus RTU client (RS-485, DE GPIO) `cat.ind.modbus_rtu_client`	Industrial & field industrial	+4.9 KB	+1.0 KB	110.0 KB	29.7 KB	12%	`cat.drv.uart2` Extra UART instance (LPUART2, interrupt driven)	Modbus serial RTU client on LPUART2 (zephyr,modbus-serial "modbus0") with DE/RE GPIO; read/write holding registers, input registers, coils. Hardware: RS-485 transceiver on pins 14/15, DE pin 2, nRE pin 3 components `subsys/modbus` +3.9 KB / RAM +1.0 KB `(merged strings)` +0.8 KB `app (application code)` +0.2 KB `subsys/crc` +0.0 KB	ok
SAE J1939 `cat.ind.j1939`	Industrial & field industrial	–	–	–	–	–	`cat.drv.can` CAN driver (FlexCAN1)		not available: No J1939 stack in Zephyr v4.4 or in the west modules of this workspace. Raw 29-bit CAN frames via cat.drv.can only.
Modbus TCP `cat.ind.modbus_tcp`	Industrial & field industrial	–	–	–	–	–	`cat.drv.uart2` Extra UART instance (LPUART2, interrupt driven)		not available: Modbus TCP needs the network stack; it is a raw ADU interface (MODBUS_RAW) under the networking catalogue, not a peripheral service.

Combined stacks

Real devices use several services together. These builds put typical sets on top of the reference app. Services share code (sockets, TCP, the heap, mbedTLS), so the measured cost is usually below the sum of the separate catalogue deltas. measured sum of separate deltas.

FLASH added to the reference app

RAM added to the reference app

Combination	FLASH added	Sum of parts	RAM added	Sum of parts	Total FLASH / RAM	Blocks	Status
SNMP over USB: USB CDC-NCM + TCP/IP + SNMP with private MIB `combo.usb_ncm_snmp`	+62.9 KB	+63.0 KB	+35.7 KB	+35.7 KB	167.7 KB / 64.4 KB	net.ipv4 usb.cdc_ncm_only net.ipv4_sockets net.base net.snmp net.snmp_traps net.snmp_private_mib	ok
Ethernet + DHCP + SNMP with traps and private MIB `combo.eth_snmp`	+72.5 KB	+72.5 KB	+43.5 KB	+43.5 KB	177.3 KB / 72.2 KB	net.ipv4 net.ipv4_sockets net.base net.dhcpv4 net.snmp net.snmp_traps net.snmp_private_mib	ok
IoT node: Ethernet + DHCP + DNS + SNTP + MQTT `combo.iot_mqtt`	+72.6 KB	+72.4 KB	+45.9 KB	+45.9 KB	177.5 KB / 74.7 KB	net.ipv4 net.ipv4_sockets net.base net.dhcpv4 net.dns net.sntp net.mqtt	ok
Secure IoT node: IoT node + TLS + MQTT over TLS `combo.iot_mqtt_tls`	+143.4 KB	+148.1 KB	+86.4 KB	+86.7 KB	248.3 KB / 115.1 KB	net.ipv4 net.ipv4_sockets net.base net.dhcpv4 net.dns net.sntp net.mqtt net.tls net.mqtt_tls	ok
Web device: Ethernet + DHCP + mDNS + HTTP server + JSON REST `combo.web_device`	+93.0 KB	+97.7 KB	+52.0 KB	+53.4 KB	197.8 KB / 80.7 KB	net.ipv4 net.ipv4_sockets net.base net.dhcpv4 net.hostname net.mdns net.http_server net.http_dynamic net.http_rest	ok
Managed connected device: DHCP + DNS + SNTP + mDNS + MQTT/TLS + HTTP REST + SNMP `combo.full_device`	+188.0 KB	+209.3 KB	+97.1 KB	+103.4 KB	292.9 KB / 125.8 KB	net.ipv4 net.ipv4_sockets net.base net.dhcpv4 net.dns net.sntp net.hostname net.mdns net.mqtt net.tls net.mqtt_tls net.http_server net.http_dynamic net.http_rest net.snmp net.snmp_traps net.snmp_private_mib	ok
Managed connected device, lean: full device + small net buffer pools + minimal shell `combo.full_device_lean`	+172.5 KB	+192.8 KB	+89.4 KB	+95.7 KB	277.3 KB / 118.1 KB	net.ipv4 net.ipv4_sockets net.base net.dhcpv4 net.dns net.sntp net.hostname net.mdns net.mqtt net.tls net.mqtt_tls net.http_server net.http_dynamic net.http_rest net.snmp net.snmp_traps net.snmp_private_mib net.small_pools tune.shell_minimal	ok

SNMP

Zephyr has no SNMP agent of its own. These builds use the external module simpleiot/zephyr-snmp v0.1.0 (BSD-3-Clause, a port of the lwIP agent; SNMP v1 and v2c over IPv4; no SNMPv3). v1 and v2c send the community string in clear text: use them only on a trusted management network.

Variant	FLASH Δ	RAM Δ	Measured against	Notes	Status
SNMP v1/v2c agent (external zephyr-snmp module) `cat.net.snmp`	+17.0 KB	+3.4 KB	`cat.net.ipv4_sockets`	External out-of-tree module simpleiot/zephyr-snmp v0.1.0 (BSD-3, lwIP-derived), not in Zephyr. Agent on UDP 161 via the socket service, with the default MIB-2 system, interfaces and snmp groups, and one install_snmp_handler() callback on a private OID. Parent is the UDP-only socket stack (no TCP); the delta includes the socket service.	ok
SNMP trap sending (external zephyr-snmp) `cat.net.snmp_traps`	+0.7 KB	+0.0 KB	`cat.net.snmp`	Adds a trap destination and snmp_send_trap_generic() to the external zephyr-snmp agent.	ok
SNMP private MIB, 3 read-only scalars (external zephyr-snmp) `cat.net.snmp_private_mib`	+0.3 KB	+0.0 KB	`cat.net.snmp`	External zephyr-snmp module. Private MIB under 1.3.6.1.4.1.32473.1 with 3 SNMP_SCALAR_CREATE_NODE_READONLY scalars, registered with snmp_set_mibs() next to MIB-2.	ok
SNMP agent over USB CDC-NCM (ENET off, external zephyr-snmp) `cat.net.usb_ncm_snmp`	+28.6 KB	+4.6 KB	`cat.usb.cdc_ncm_only`	External zephyr-snmp module (not in-tree) on the USB CDC-NCM network interface, with the Ethernet MAC off. Same conf and stub as cat.net.snmp. Delta = SNMP agent + BSD sockets + socket service on the NCM IPv4/UDP stack.	ok
SNMP agent without MIB-2 interfaces group (negative delta) `cat.net.snmp_no_mib2_if`	-1.4 KB	+0.0 KB	`cat.net.snmp`	External zephyr-snmp agent with SNMP_AGENT_MIB2_INTERFACES=n; the delta is minus the cost of the ifTable group.	ok
SNMP over USB: USB CDC-NCM + TCP/IP + SNMP with private MIB `combo.usb_ncm_snmp`	+62.9 KB	+35.7 KB	`app`	Ethernet over the USB cable (ENET off), IPv4 + UDP + TCP + sockets, static IP, SNMP agent with traps and a private MIB.	ok
Ethernet + DHCP + SNMP with traps and private MIB `combo.eth_snmp`	+72.5 KB	+43.5 KB	`app`		ok

Not available on this board

Services that Zephyr has but that cannot run on a Teensy 4.1 without extra hardware, or that Zephyr does not provide.

MQTT over WebSocket (on WebSocket client) (cat.net.mqtt_ws): Does not compile in Zephyr v4.4.2. subsys/net/lib/mqtt/mqtt_transport_websocket.c uses NET_ERR/NET_DBG/NET_INFO but does not include zephyr/net/net_log.h (implicit declaration errors). Fix upstream with one include line; then remove this na.
OpenThread (Thread mesh) (cat.net.openthread): Needs an IEEE 802.15.4 radio; Teensy 4.1 has none (an RCP over UART/SPI would be external hardware).
IEEE 802.15.4 L2 / 6LoWPAN (cat.net.ieee802154): No 802.15.4 radio on Teensy 4.1.
Bluetooth LE (and IPSP / BLE networking) (cat.net.bt_ipsp): No Bluetooth controller on Teensy 4.1 (an external HCI controller over UART would be needed).
Native Wi-Fi (wpa_supplicant, hostap) (cat.net.wifi_native): No on-chip Wi-Fi. Only an offloaded AT modem (cat.net.esp_at) applies.
Ethernet bridge (cat.net.bridge): Teensy 4.1 has one Ethernet port; a bridge needs two or more.
DSA (distributed switch architecture) (cat.net.dsa): No Ethernet switch chip on Teensy 4.1.
10BASE-T1S (cat.net.t1s): Needs a T1S MAC-PHY (for example LAN865x on SPI); the board has a DP83825 100BASE-TX PHY.
MCUboot bootloader (cat.sys.mcuboot): MCUboot is a separate sysbuild image; the runner builds only app/. On Teensy 4.1 the HalfKay loader (on the MKL02 helper MCU) writes the image at 0x60000000 and the ROM boots it from the FlexSPI boot header, so MCUboot would have to own offset 0 and the app would move to a slot; teensy_loader_cli cannot write slots. See cat.sys.mcuboot_chainload for the app-side cost.
EDHOC (uedhoc) key exchange (cat.sec.edhoc): uedhoc src/edhoc/cert.c uses the mbed TLS 3 PK API (MBEDTLS_PK_ECDSA, mbedtls_x509_crt sig_pk). Zephyr v4.4.2 ships mbed TLS 4 / TF-PSA-Crypto, where these identifiers are private and not reachable from x509_crt.h, even with MBEDTLS_X509_CRT_PARSE_C and MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS. The module does not compile.
Newlib C library instead of picolibc (cat.lib.newlib): Zephyr SDK 1.0.1 ships only picolibc for arm-zephyr-eabi (no newlib libc.a/libc_nano.a), so NEWLIB_LIBC_SUPPORTED is n and CONFIG_NEWLIB_LIBC does not exist in the build. Use tune.minimal_libc for a libc comparison.
Rust application support (cat.lib.rust): No Rust toolchain (rustc/cargo with the thumbv7em target) in the Pixi environment or the Zephyr SDK, and the zephyr-lang-rust module is not in the workspace.
SAE J1939 (cat.ind.j1939): No J1939 stack in Zephyr v4.4 or in the west modules of this workspace. Raw 29-bit CAN frames via cat.drv.can only.
Modbus TCP (cat.ind.modbus_tcp): Modbus TCP needs the network stack; it is a raw ADU interface (MODBUS_RAW) under the networking catalogue, not a peripheral service.
Bluetooth (on-chip radio) (cat.drv.bt_native): i.MX RT1062 has no radio. Use cat.drv.bt_hci_uart with an external controller.
Wi-Fi (on-chip radio) (cat.drv.wifi_native): i.MX RT1062 has no radio. An external ESP32 with ESP-AT firmware over UART (drivers/wifi/esp_at) needs the network stack; it belongs in the networking catalogue.

Method and limits

Leave one out (abl.*): the reference app minus one module; module cost = reference app − variant.
Catalogue (cat.*): a parent build plus one service; cost = variant − parent.
Library callers. The linker removes unused functions (--gc-sections). Library services therefore get a small shell command that calls their main API. It is linked but never run.
FLASH = bytes of all loaded sections in zephyr.elf (code, constants, initial values of data). The linker’s own “FLASH used” line also counts a 1–3 KB reservation that moves in steps, so the study does not use it.
RAM region. The teensy41 board puts all static RAM in the 256 KB OCRAM region by default. DTCM, ITCM and OCRAM2 (768 KB together) stay unused unless the application places data there, so percentages refer to the 256 KB region.
RAM = static RAM from the linker summary (data, bss, stacks, buffer pools, heaps) at Kconfig defaults. It is not run-time heap use, and the defaults are not minimums: smaller network buffer pools alone save about 7 KB.
Costs do not add up exactly. They depend on the parent and on what is already present. The combined-stack section shows the size of this effect.
Every Kconfig line is checked. A requested value that does not reach the final .config marks the build as inexact. A symbol that does not exist in the tree causes a warning.
Component attribution comes from zephyr.map. Zephyr’s own rom_report needs a Python package that this workspace does not install.

Reproduce

Workspace: the reference app with a west workspace for Zephyr v4.4.2 and the extra modules. The Python tools come from Anaconda main through Pixi.

pixi run --frozen python study/run.py --jobs 4 — build every variant that is new or changed (resumable)
pixi run --frozen python study/delta.py [REGEX] — text table of sizes and deltas
pixi run -e report python study/report.py — this page and the 4K PNG plots

Variant definitions: study/variants/*.yaml. Rules and fields: study/README.md.

PNG plots for slides (3840×2160)

Generated 2026-10-25 by study/report.py from 305 builds. Zephyr v4.4.2 · Zephyr SDK 1.0.1 (GCC 14.3) · board teensy41 · picolibc · -Os.