Reducing PX4 flash usage on CUAV X7 Pro (cuav_x7pro_default) while keeping CAN tools

PX4 Autopilot
1

I’m building PX4 for a CUAV X7+ (target: cuav_x7pro_default) and I’m hitting a flash overflow at link time:

  • .text will not fit in region FLASH

  • FLASH used: ~1,989,072 B / 1,920 KB (overflow ~22,992 bytes)

Goal: I want a working NSH shell and specifically to use candump and cansend on the flight controller (SocketCAN / CAN utils). I don’t need Ethernet or other unused peripherals/features.

Questions:

  1. What are the recommended PX4 features/modules to disable to reduce flash size on this target, while keeping CAN (FDCAN) + candump/cansend working?

  2. In NuttX menuconfig, I see STM32H7_HAVE_ETHERNET=y / ethernet-related options. Where is the correct place to disable ethernet (or does PX4 board support force it on)?

  3. Any known “big hitters” for flash on H7 targets (e.g., uXRCE-DDS, navigator features, flight mode manager tasks, logging, etc.) that are safe to disable for a minimal CAN-testing build?

Info:

  • NuttX config file exists at: build/cuav_x7pro_default/NuttX/nuttx/.config

  • CAN utilities are enabled: CONFIG_CANUTILS_CANDUMP=y, CONFIG_CANUTILS_CANSEND=y

  • Using STM32H7 FDCAN1

If anyone has a minimal working config or a list of BOARD_* / CONFIG_* items to turn off for this target, I’d really appreciate it.

Thanks,
Kirubakkar Ravichandran