DUEX GPIO configuration

npretor · 31 Dec 2020, 22:32

I'm currently running a Duet and Duex5, and trying to control some external pumps and solenoids. I would like to trigger the solenoid using a gpio, but I have read the documentation and it's as clear as mud to me. I don't need high current, just a simple on and off for switching a MOSFET through gcode. I have no hotends and no fans, i'm using the Duet+Duex for controlling fluid dispensing on the E3D toolchanger.

So far I have tested:

Turning on and off existing fans I/Os with:
M106 P7 S1.0. ; Turns on Fan7(according the PCB label)
I have also set the fan voltage jumper to both 5V and 12V with no detectable voltage
M307 P27 I-1. ;Disable fan 7? Not sure
M42 P27 S1.0 ;Turn on what was Fan7 output to high?

I also tried using the Duex GPIO pins which is my preferred method, but I honestly find the pin documentation sheet to be unreadable:
https://duet3d.dozuki.com/Wiki/Duet_2_Pinout_table.
What am I missing? Is there an example I can go off of that someone else had done for triggering something similar?

Board: Duet WiFi 1.02 or later + DueX5
Firmware: RepRapFirmware for Duet 2 WiFi/Ethernet 2.05.1 (2020-02-09b1)
Duet WiFi Server Version: 1.23

whosrdaddy · 1 Jan 2021, 20:56

@npretor said in DUEX GPIO configuration:

M307 P27 I-1. ;Disable fan 7? Not sure
M42 P27 S1.0 ;Turn on what was Fan7 output to high?

If you want to use M42, you must first unmap the fan port.
This is done by command M106 P7 I-1, P7 refers to Fan #7 on the duex board.
Now you can use M42 P27 S255 to set the pin High or M42 P27 S0 to set the pin low.
P27 is the logical pin number for Fan #7 as shown in the documentation
Be aware that the Duet board switches V- of the port, V+ is set to the Fan voltage jumper selection

npretor · 2 Jan 2021, 01:01

Ok thank you, appreciate the reply. I'll give it a shot!