Remora - Rpi Software Stepping Using External Microcontroller via SPI

I will be more than happy, to share something I know how.
meanwhile, I added your suggestion to .hal file. did not work.
  

Ok, thanks Viren.


Hmm that is odd for sure. I am only using RPI4. I dont know exactly the difference between RPI3 vs RPI4 in regards to SPI

What board are you using with your setup? I dont think it should matter, but just wondering

Also, how long is your cables?
I had to use shorter cables than I normal (3d printer boards I was using around 100-130mm) with my nucleo setup, I had to use less than 100mm cable length.

ok, just to have our bases covered
- leave the base_freq entry in hal regardless, we need that for the nucleo repo
- test with axis gui, (shouldnt be any different but lets make sure)
- try the flexi-hal RPI4 image, that one should positively work software side.
- copy the comp from your RPI 3 setup. I dont think Ive made any changes since you first installed, but just double check

Re compiled,
Re halcompiled remora.c.
All working in RPI 3B.
Changed the Dupont cables for 100 mm.
Just to check I intensely pulled MOSI cable from RPI 3B, same result as I have with RPI 4B.
Estop comes out but on jog jont 0/1 error.

So all in all I had fried my pin 19(MOSI) in RPI 4B.

Now I will have to wait for ethernet branch!

That is unfortunate to hear viren. At least you could reproduce the error...

You might have better luck changing the linuxcnc component to use RPI SPI1 instead

pinout.xyz/pinout/spi

Hello, just thought I would share this project based on Remora for STM32F103C8 (blue pill).
github.com/iforce2d/weenyPRU

Most of the component side is as for Remora, the firmware is written from scratch except for the DDS section. It uses STM32 HAL and is quite narrow in scope compared to Remora, there's no nice way to change settings and no considerations for other microcontroller targets.

The idea was to see how far I could get with a lowly blue pill, and how small and cheap a LinuxCNC build could be and still have reasonable performance. I'm building a little solder bot that fits on an A4-size paper, and it seemed silly to have a big PC twice the size of it to run the controller. I want to use a PiZeroW, first I tried software stepping but that was pretty slow, so I started searching for SPI based methods and discovered Remora. With an external PRU the ZeroW actually holds it together pretty well, at least when not also running the GUI.

Anyway, the blue pill works but made for an awfully messy wiring setup, so I designed a PCB to keep everything tidy. Some info about that here if anyone is interested: 

Hey iforce2d, lookin good. I am interested to see your PCB for this. Ive started working on a cheap RPI shield to work with the STM32 bluepill and blackpill as well.
I am interested in poking around your repo though, to see whats going on. I like the analog in.

If you are interested in working with mainline remora, Ive made a bluepill/blackpill repo. I havent made an SD card version yet, but I can cook one up if you are interested, although you seem capable enough on your own.
edit, right, removing the sd was the only way i could get it small enough for the firmware

github.com/cakeslob/Remora/tree/blackpill