Topics created by arvest

@arvest said in challenge: controlling 88 output pins:

So to summarize: you would use a separate valve controller (arduino + shift registers) to which you send the pattern for the current layer through M118 before starting the layer

I guess it would be safer and faster, when the arduino part holds the pattern data on it's own SD-card. The duet would only control the moves and send a "line number" or a next line signal to the valve controller.

I'm almost tempted to say, a good old RAMPS-controller could do the trick without UART or SPI bottleneck. Everything is onboard, except the shift registers.

Digging around in the Firmware and documentation, got me to https://duet3d.dozuki.com/Wiki/M578 and from there to using the P parameter on the G1 command. It allows you to set a pattern of bits, mapped to GPIO pins defined in the M670 command.

This I think is exactly what I am looking for, and it seems the SUPPORT_IOBITS flag is enabled for the Duet2 WIFI (i.e. DuetNG), so it should work out of the box. I'll will try it as soon as I have the opportunity.