Shift reg with blackpill

[body32003]

Hello
First of thank you for the awesome work
I'm still using grbl mega 5x
Secondly I'm looking into building a blackpill cnc board that uses 74hc595 shift reg to expand the outputs and step dir pulses
Can it be done

[terjeio]

Can it be done

Yes, should be doable. However, If for a one-off project then IMO it is not worth it unless it is a coding excercise.

FYI I made a patch to output XY position to audio DACs via I2S DMA as an experiment, this without any changes to driver.c. I2S DMA could be used for step/dir output in a similar way as how it is done for the ESP32, and the experimental code might help you to get started.

[body32003]

Yeah I noticed that bearing's esp 32 uses i2s while Picocnc uses spi
I'll try that for blackpill
And who know maybe I'll be able to make a replicable thing that's easy enough for ppl to use
Maybe a shield of some sort for the blackpill to mount a ramps 1.4

[terjeio]

Picocnc uses spi

FYI it uses PIO programs to generate and output the pulse and direction signals with programmable length and delay, not plain SPI.