Remora - Rpi Software Stepping Using External Microcontroller via SPI

Hey there

After having successfully used a NVEM flashed Remora via Ethernet for a while, I want to use an old 3d printer board (SKR E3 Mini v2.0) via SPI for my Plasma. It took me a while but eventually i got it to respond correctly via UART, and am currently sitting at

Starting the SERVO thread
Registering interrupt for interrupt number = 28
        power on Timer 2

## Entering IDLE state

Problem is that I struggle to make any communication via SPI. I think I triple checked every wire. As the SKR Mini Configuration in the repo seems to be for a version 1.2 of the board i modified the pins both in the firmware and config.txt, taking care of not using anything that may conflict with other function. But so far no nothing. 

Is there any way to approach debug/test anything further to narrow down why the comms doesn't seem to work?

Thanks a lot,
Alessandro

You should post complete serial console output. It will make diagnosis easier.
You should start LinuxCNC from terminal. And terminal window what msg you get when you press estop button in lcnc gui. Is it spi_payload = 0 or something else?
Did you compiled and installed remora-spi lcnc component from same repository?

Not really sure whats going on now as I run into segfaults. I havent changed a thing on linuxcnc side, i just changed the config.txt on the SD Card

line 977: 2610 Segmentation fault $EMCDISPLAY -ini "$INIFILE" $EMCDISPLAYARGS $EXTRA_ARGS

Before that I haven't seen anything in the terminal or anywhere, thats why I'm a bit puzzled. Yes I compiled it from main branch, using OS6 Version for the Firmware and likewise for the hal component.

Is there a way to just test it with the halcmd? I tried loading the remora component, but struggle beyond. Show pins shows no active session.

Both the debug file and the regular logfile are basically empty with no specifics concerning the error.

Thanks!

So in the meanwhile, without working UI I tried to test comms with halcmd.

Does
4 bit IN TRUE remora.SPI-enable
4 bit IN TRUE remora.SPI-reset
4 bit OUT TRUE remora.SPI-status

actually mean there was some comms? UART doesnt show anything though.

It seems remora is working ok. There must be issue with GUI. Try using axis gui first. UART just shows startup msgs on remora.

So Axis starts, and remora.SPI-status is true too. Resetting the MCU actually throws SPI Errors. I think that looks fine. Unfortunately I can't toggle the emergency switch.

I looked at the PRU-reset pin and its on FALSE. is that how it should be? Am I missing something obvious?

I'm just using the standard HAL configuration from the doc:

Thanks, Alessandro

I made some progress, SPI wasnt likely working properly before, as I had chosen PB9 for the pru-reset. Turns out PB9's timer is already occupied so no PWM. I change to PB15 which is usable for PWM and now i'm getting a 

When trying to unlock the e-Stop.

I just realised I still had SPI_clk_div set to 16, after setting it back to 32 or 64, the errors are gone, but i'm at square one again, no error on e-stop deactivate.

the fact that you get a bad spi payload is good, keep it at 32 probably

This may sound forward of me, but how long is your cable?

About 8cm-ish. pretty standard dupont wires for breadboards