Remora - Rpi Software Stepping Using External Microcontroller via SPI

Hello,I have a new MKS v1.3 and want to prepare it for use.
I will solder the jumper as described
but the cable information is difficult for me to follow.

The wiring diagram shows the RESET wire  
from RPi GPIO25  
to Px.xI

I think this Px.x is used for RESET becasue that is it's purpose for it in SKR v1.3

@Doogie, you have used the MKS v1.3,
so please tell me where Px.x connects.

thanks TomP

EDITt:
YAY!
the MKS v1.3 came out of EStop on 2nd press of F1, sometimes on 1st press.

I have RPi gpio25 still un-attached, waiting for information.

I can home all 3 axis using HOME ALL button
( There is no machine connected, so no limit switches )

I get following errors on all 3 joints, even at very slow jog rates ( 62mm/min.)
But this is a big step fwd from the SKR v1.3.

I can see the commanded postion, and the f-error rises with each tap of the jog key,
but no reduction of f-error,  tells me no steps are being fed back...or no command sent.
I will re-eable debug prints in remora.c
tomorrow,

What is the expected status led appearance (on MKS v1.3) ?
All 5 on solid?

thanks
TomP 

Good to see you have SPI working and you are moving motors.

As for GPIO25 connection you can decide what you want and set that up as in your config.txt. I currently don't use it so leave it floating on the MKS side. But if you want to connect it, look at the config.txt for the SKR v1.4 and you'll see at the top "reset pin" defined. Please look at your board pinout, and use an available pin number and add that to your config.txt file.

I'm currently only running on a 3D printer and laser cutter so a wired E-Stop to the board has not been necessary.

no motion yet.
Axis DRO remains at 0 untill f-error limit is reached.
No steps at all.
I have to see if the command is received at MKS m
and if any feedback is sent back to Pi.
thanks, tomp

Are you new to LinuxCNC?  Asking because I am and following errors were driving me nuts considering there are no encoders so there's no feedback to create following errors. Are you using the remora-xyz LinuxCNC sample configuration files?

I would not expect those to be throwing off following errors. If no maybe consider it or maybe you'd like to look at some LinuxCNC hal and ini files I've used to see if sections fit your needs and illuminate possible changes to your setup. github.com/dlarue/Remora/tree/ender3-updates

It is handy to have the rPi rx/tx setup for debugging but I've also found that you will see Remora output on the console window you started LinuxCNC on when things go wrong.

Bari wrote:

STM32's are also hard to find right now, but that won't last forever.

I'm looking at porting this to STM32 for the future. Feel free to beat me too it

Help with a port to the STM32 would be greatly appreciated. Mbed gives some head start but there is no MODDMA version for the STM32 so the whole DMA communication will need to be coded from scratch. Can be done as this is how I started with the Arduino Due.

Porting the threads would be less involved I think.

tjtr33 wrote:

Hello,
Is there a difference between the diagram for skrv1.3 spi cable and your cable foto?
The disgram on readthedocs show a wire from what is labeled "p1.31" ( pin 4 of EXP2)
but your foto shows that socket empty., and instead a wire is connected to 3.25. ( pin 6 of EXP2)
Do I correctly see p1.31 is empty in your foto?
I am not geting the expected results and want to try correctly.
I just tried with what i see in the foto and still get bad spi ffffffff hitting F1 estop repreatedly
I then moved the 'reset' wire to the p1.31 and got same
Then I tried external 12V ps for skrv1.3
using screw terminal  '12/14' and GND, moved jumper from 5V to INT.
Result is same ( spi cable is from p1.35 on skr to reset gpio25 on rpi 3B+)
also tried with reset line from p3.25 to rpi gpio25, same ffffffff

it does not work as expected
but i DO need to resolve the diagram vs foto for later

the pin in question really is p1.31 and really is on pin2 of EXP2.
(not on pin 6 ). This is from the SKR V1.3 config.txt.

My skr v1.3 is no longer a candidate for Remora.
I have recieved an MKS v1.3 and will make an SPI cable for that.

thanks,
tomp

 

Hi tomp, 

The reset can be wired to any available pin and setup accordingly in the config.txt file (I'll need to note this in the docs). On the Raspberry Pi it is hard coded in the component though. Really strange, but it would be super helpful to have the output from the debug serial so see if the config.txt file is being de-serialised correctly.

BR
Scott