On 8/11/24 20:53, John Larkin wrote:
I want to use an Raspberry Pi 400 (the keyboard thing) as the
dev/debug system for an RP2040 based product.
https://www.amazon.com/Raspberry-Computer-Keyboard-Layout-Kabel/dp/B08QCQVWH2
It has a 40-pin connector on the back. Various sources say that pins 1
3 and 5 are either GPIO ports 8 9 and 7 or maybe 2 3 and 4.
Sometimes the pins are labeled WPI and BCM. Wot's that?
https://www.amazon.com/Coolwell-Waveshare-Raspberry-Adapter-Expansion/dp/B08RZCR7S8
I can fix most mistakes there in software, just by reassigning port
names. But two pins are critical, the SWDIO and SWCLK debug lines out
to a Pi Pico or to the 2040 chip.
I suspect that on the Pi 400 pin 18 is GPIO5 = SWDIO and pin 22 is
GPIO6 = SWCLK.
Is that right? Does that actually work?
yes I believe that is correct, looks like the PI400 uses the wiringpi
numbering instead of that actual raspberrypi GPIO numbers
https://pinout.xyz/pinout/wiringpi
anyway afaict the debugger just bitbangs the SWD and can be build to use
any available GPIO
I also note that some people also connect the UART tx/rx between the
Pi400 and a Pico for debugging. Should I do that too? Does it help
software development?
definitely, it's an easy way to control and messages back and forth when running something that's realtime and can't just be stopped to check
things with a debugger
--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)