What's the best way to use the Pi Debug Probe with this library?

[Zelzahn]

Greetings, I'm coming from Rust so Go + Embedded is still a bit new for me. I have a Raspberry Pi Pico linked up with a Pi Debug Probe. Currently, I do tinygo build -target=pico main.go, followed with probe-rs run --chip RP2040 main.elf.

Is there any way to make tinygo flash call the probe-rs command via any config file? Or is there any other tooling better integrated?

[kenbell]

I haven't played with it for a couple years, but with a suitable version of openocd you should be able to do things like:
tinygo gdb -target=pico main.go

Last time i played with it, you needed a custom / non-released version of openocd - but it looks like the 0.12.0 release should have everything needed: https://openocd.org/openocd-0120-released.html

[dufguix]

Why do you use probe-rs ?
I am curious.

[aykevl]

Usually tinygo flash -target=pico will work out of the box. I think you can also use prope-rs run but I haven't tried it.

(I think probe-rs is a really clean debug probe tool, I might investigate using it for TinyGo instead of OpenOCD at some point).

[lgamma]

Hi there, I'm moving the first steps with TinyGo in order to evaluate performance and development effort for a new project based on RP2040 (or maybe 2350). Looks very easy to manage source code and tool-chain.

What is pedantic, in my opinion, especially on first usage is compiling as UF2, press BOOT/RUN and flash the image to the target.

I'm used to compile directly to a binary image (evt. HEX format) then upload via SWD and have an UART monitor always connected to the PC instead of going through the USB device.

According to the documentation, it is possible to specify a .bin extension to the -o option in order to generate a binary image.

So I just got the basic blinky example to compile then upload with two simple bash scripts.

Build script:

#!/bin/bash

TARGET=pico
IMAGE=hello-pico.bin

tinygo build \
-target=$TARGET \
-serial=none \
-scheduler=none \
-panic=trap \
-o=$IMAGE \
-size=full

Upload script:

#!/bin/bash

SERIAL=E6616407E35E482F # RASPBERRY PI debug probe (original)

TARGET=rp2040
IMAGE=hello-pico.bin

edbg \
-b \
-s $SERIAL \
-t $TARGET \
-x 100 \
-c 16000 \
-epv \
-f $IMAGE -o 0x0

Loading generated .bin with a simple EDBG (CLI tool) the target device remains mute even after successful programming and verification.

Here the full output for reference:

(.venv) luca@desktop2:~/tinygo/hello-pico$ ./build.sh 
   code  rodata    data     bss |   flash     ram | package
------------------------------- | --------------- | -------
      0       6       0       2 |       6       2 | (padding)
    372       0       0       7 |     372       7 | (unknown)
    240       0       0       0 |     240       0 | /usr/local/lib/tinygo/targets
    866       0       0       0 |     866       0 | C compiler-rt-builtins
      0     168       0       0 |     168       0 | C interrupt vector
     14       0       0       0 |      14       0 | C picolibc
      0       0       0    4096 |       0    4096 | C stack
     20       0       0       0 |      20       0 | device/arm
     18       0       0       0 |      18       0 | device/rp
    316       0       0      41 |     316      41 | machine
     44       0       0       0 |      44       0 | main
    664       0       0      38 |     664      38 | runtime
    180       0       0       0 |     180       0 | runtime/volatile
     28       0       0       0 |      28       0 | sync/atomic
------------------------------- | --------------- | -------
   2762     174       0    4184 |    2936    4184 | total

(.venv) luca@desktop2:~/tinygo/hello-pico$ ./upload.sh 
Debugger: Raspberry Pi Debug Probe (CMSIS-DAP) E6616407E35E482F 2.0.0 (S, 2)
Using CMSIS-DAP v2
Clock frequency: 16.0 MHz
Resetting... done.
Target: RP2040 (Rev B2)
Flash size: 2 MB
Erasing......... done.
Programming... done.
Verification.... done.

Loading the bin image to Hex Editor (VS Code extension), this file appears as 12 consecutives UF2 header blocks of 512 bytes.

May be the .bin export broken for "pico" target?

[aykevl]

You can use SWD instead if you prefer, by connecting a debug probe and adding a flag like -programmer=cmsis-dap or -programmer=stlink to TinyGo. It will use the specified programmer with OpenOCD instead.