rjw57/pico-playground

Raspberry Pi Pico playground

Building

$ mkdir build
$ pushd build
$ PICO_SDK_PATH=$HOME/projects/pico/pico-sdk cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=1 ..
$ popd
$ cmake --build build --parallel

Hardware

Connect the output of SYNC and VIDEO to the output by means of two resistors. The ideal resistor for SYNC is 575 ohms and for VIDEO is 246 ohms. Using 560 and 220 should be OK. The output should be connected to ground via a 75 ohm resistor.

Picoprobe

Configuration for udev allowing members of the dialout group to connect to a picoprobe is provided in the udev directory. To enable:

$ sudo cp udev/99-picoprobe.rules /etc/udev/rules.d/
$ sudo udevadm control --reload-rules &&  sudo udevadm trigger

One should then be able to start openocd as an ordinary user after building and installing it as per the pico getting started guide:

openocd -f interface/cmsis-dap.cfg -c "adapter speed 5000" -f target/rp2040.cfg -s tcl

If using a RP2040-GEEK, use the appropriate connector cable to connect the SWD port of the RP2040-GEEK to the SWD pins of the pico. Connect the UART cable according to the following table:

RP2040-GEEK	Pico pin
GP5	1 (GP0)
GND	3
GP4	2 (GP1)

The serial console can be connected to via, e.g. minicom:

minicom -b 115200 -o -D /dev/ttyACM0

Start the debugger via:

gdb -ix gdbinit ./build/playground/playground.elf

The bld and mri commands are provided in the gdbinit file to rapidly re-build and load and/or reset the pico.