Board List

The repo defines three PROVES Flight Controller boards under boards/bronco_space/. All three use the RP2350A SoC on its Cortex-M33 core. Select one with BOARD= in settings.ini. See Specifying Board Configuration.

Boards

Board	`BOARD=` string	Vendor (`board.yml`)	LoRa driver	Flash (`.yaml`, KB)
v5c	`proves_flight_control_board_v5c/rp2350a/m33`	Bronco Space	`CONFIG_LORA_SX127X`	4096
v5d	`proves_flight_control_board_v5d/rp2350a/m33`	Bronco Space	`CONFIG_LORA_SX127X`	16384
v5e (default)	`proves_flight_control_board_v5e/rp2350a/m33`	The Spacecraft Company LLC	`CONFIG_LORA_SX126X`	16384

v5e is the default because settings.ini sets BOARD=proves_flight_control_board_v5e/rp2350a/m33.

The shared v5 base

proves_flight_control_board_v5/ is not a board. It has no board.yml, so Zephyr cannot build it. It holds the shared files:

proves_flight_control_board_v5.dtsi and proves_flight_control_board_v5-pinctrl.dtsi. Each variant .dts includes the dtsi.
Kconfig.defconfig. Each variant Kconfig.* file sources it.

The base defines the flash partitions. MCUboot runs in swap-using-offset mode (bootloader/sysbuild.conf), so it swaps between two slots: slot0_partition and slot1_partition.

Partition	Label	Offset	Use
`boot_partition`	`mcuboot`	`0x000000`	MCUboot
`slot0_partition`	`current`	`0x100000`	Primary slot. The application runs from here (`zephyr,code-partition`).
`slot1_partition`	`golden`	`0x200000`	Secondary slot. `FlashWorker` writes uploaded images here and MCUboot swaps them in. After a swap it holds the previous image, so it is not a fixed golden image.
`slot2_partition`	`test`	`0x300000`	Defined but unused.
`storage_partition`	`storage_partition`	`0x400000`	Application file system

What differs between variants

Each variant .dts starts from the base and overrides a few nodes.

	v5c	v5d	v5e
Watchdog LED (`led0`)	GPIO 24	GPIO 23 (base)	GPIO 23 (base)
LoRa radio	SX1276 (base)	SX1276 (base)	SX1262 (`E22-400M30S`)
LoRa DIO pins	GPIO 13, 12	GPIO 14, 13 (base)	DIO1 on GPIO 14, BUSY on GPIO 13
MCP23017 GPIO expander	`i2c1` (base)	`i2c1` (base)	`i2c0`, reset on GPIO 20
S-band RX/TX enable	not defined	not defined	MCP23017 pins 4 and 7
USB product string	`PROVES Flight Control Board v5c`	`PROVES Flight Control Board v5d`	`PROVES Flight Control Board v5e`

v5d adds no overrides. It is the base as written.

v5e also sets these LoRa properties: reset on GPIO 6, TX enable on GPIO 21, RX enable on GPIO 22, a 1.8 V TCXO on DIO3, and rx-boosted. It removes the rf2-io2 and rf2-io3 inputs, because they use MCP23017 pins 4 and 7.

These files are the same for all three variants:

board.cmake: registers the openocd runner (CMSIS-DAP by default, override with RPI_PICO_DEBUG_ADAPTER), the jlink runner (RP2350_M33_0), and the uf2 runner (RP2350).
support/openocd.cfg: defines the set_adapter_speed_if_not_set helper that board.cmake calls.

Flashing

The Makefile makes these files at the repo root:

File	Made by	Contents
`mcuboot.uf2`	`make build-mcuboot`	MCUboot bootloader, UF2 format
`mcuboot.elf`	`make build-mcuboot`	MCUboot bootloader, for SWD
`bootable.uf2`	`make build`	Signed application (`build-artifacts/zephyr.signed.bin`) as UF2, placed at `0x10100000` (`slot0_partition`)
`bootable.signed.hex`	`make build`	Signed application, for SWD

flowchart LR
    A[make build-mcuboot] --> B[mcuboot.uf2]
    C[make build] --> D[bootable.uf2]
    B -- "first time only" --> E[(Board in UF2 mode)]
    D -- "every code change" --> E

Warning

make build-mcuboot always builds MCUboot for v5e. tools/bin/build-with-proves passes -b proves_flight_control_board_v5e/rp2350a/m33 and does not read settings.ini.

UF2 over USB

Put the board into UF2 bootloader mode. It mounts as a USB drive with a name like RP2350. If the board already runs F Prime, send ReferenceDeployment.bootloaderTrigger.TRIGGER_BOOTLOADER from the GDS. The BootloaderTrigger component reboots the board into USB boot mode.
Find the drive path.
```
# macOS
ls -lah /Volumes

# Linux
findmnt
```
On Windows, find the drive letter and the drive name, for example /d/RP2350.
First time only (new board, or a board coming back from CircuitPython): build and copy MCUboot.
```
# In proves-core-reference
make build-mcuboot
cp mcuboot.uf2 [path-to-your-board]
```

Build the application, put the board back into UF2 mode, and copy the image.

# In proves-core-reference
make build
cp bootable.uf2 [path-to-your-board]

Repeat step 4 after every code change.

Note

Copy bootable.uf2, not build-artifacts/zephyr.uf2. MCUboot only boots images signed with its key. The build signs with keys/proves.pem (CONFIG_MCUBOOT_SIGNATURE_KEY_FILE in prj.conf), and bootable.uf2 is made from the signed binary.

Warning

If you flash a bootloader built on another computer, copy that computer's keys/proves.pem too. Otherwise the images you build will not boot.

SWD with a debug probe

The Makefile can flash over SWD with OpenOCD and a CMSIS-DAP probe. The first run clones and builds the Raspberry Pi OpenOCD fork into tools/openocd.

# In proves-core-reference
make debug-install mcuboot.elf
make debug-install bootable.signed.hex

Flash MCUboot first. bootable.signed.hex only covers slot0_partition. The CI flash step uses the same order.

make debug starts OpenOCD against the probe without flashing.