Remora - Rpi Software Stepping Using External Microcontroller via SPI

Why not use a cheap Parallel cnc breakout you can get nice ones sub 15 dollars, then you just make a STM to DB25 board and done... this is what the GrblHal users are doing with the 32bit STM blue/red/black Pills ...easy simple solution to not reinvent the wheel.

That's kinda what I am doing.
I use a lpc chip hooked into one of those break out boards for added protection and the use of the pwm to 0-10v and relay.

I know before the virus I was able to pick those board up from Ali for around 3$

Might be an option for those IF the optos switch fast enough and you can deal with the lack of 0V for the spindle control on many versions of those. It would be nice to find a source for these that have the good parts vs the crappy slow optos. My interests in a STM32 board would include encoder feedback.

The porting of Remora to STM32 is going well and is now working with basic modules.

github.com/scottalford75/SKRV2-Mbed-OS5/...ain/OS5-SKRv2-Remora

LinuxCNC comes out of eStop and the LinuxCNC test ngc files run.

Got something strange to work out with the DMA memory to memory transfer though. Currently using a standard copy, but at least things are working. Any STM32 DMA gurus? I've encapsulated the SPI DMA slave into it's own class "RemoraSPI". Something not quite right with how I'm passing in pointers to global structures.....

Remora for STM32 is turning motors! A few things to sort out still. ADC for thermistors and getting the TMC2209's talking over UART. Only having to port the hardware drivers has meant quick progress once they are done.

So all other things are working? Encoders and pwm gens?

How to hook up encoders to a SKR V2?

Aaroncnc wrote:

So all other things are working? Encoders and pwm gens?

Hi Aaron, only software PWM at the moment. I need to look into the hardware PWM side of the STM32 to port that over. Also how to use the encoder features of the STM32 timers. Looking forward to being able to have more than one hardware encoder module.

It looks like we have only one hardware encoder open for use on the SKR2 board. Pins PE9 and PE11 on the EXP1 header can be used with Timer 1 in encoder mode.

There are also encoder capable pins assigned to E0 and E1 drivers. If one of these is not being used then it would open up another one or two. The E0-CLS and E1-CLS headers could be used.

At lease one readily available encoder interface is better than nothing..

One encoder is enough to enable rigid tapping with an encoder on the spindle. So one could have 3-4 axis for stepping on a mill and rigid tapping using the SKR2. Already beats mach3.