Preferred GPIO pins? For Relay Control Duet 3 Mini 5+

gumby

I am trying to control a 120v power supply to control a 12v pump from my Duet using Gcode.

I see a number of available ports but wasn't sure if there was some preferred pins to use for that task.

Here is the type of 5V relay board I am using...

alt text

The pins I see readily available on my duet, are IO5, IO6, OUT1 and OUT6.

I don't want to ask stupid questions, it seems straight forward, but I am worried I will miss some common pitfall and brick my board or something.

Is there any wisdom of which pins to use, or are they all fair game?

My board is a Duet3 5+ wifi.

Thanks in advance,
Gumby

Phaedrux

Any of the out ports would work since you're just switching a relay.

https://docs.duet3d.com/en/Duet3D_hardware/Duet_3_family/Duet_3_Mini_5+_Hardware_Overview#inputoutput

As for controlling it, that would maybe depend on what the intended use of the pumps is.

https://docs.duet3d.com/en/User_manual/Connecting_hardware/IO_GPIO

A Former User

This post is deleted!

gumby

@Herve_Smith

Thanks,

I am just trying to do my due diligence before posting. I have been on forums where everything is sprayed on there without thought.

Gumby

gumby

@Phaedrux

I am trying to do a liquid cooled hotend. I have a Thermaltake 12V pump, but all my other electronics on the Predator is 12V, so I thought the best way would be to control the pump from Gcode.

Gumby

gumby

@Phaedrux

I see the M950 command to set up a pin. Where I am getting confused is how do I know what type of flag to add to the command.

Here is what it says...

  Hnn Heater number
Fnn Fan number
Jnn Input pin number (RRF 3.01 and later only)
Pnn or Snn Output/servo pin number.
Rnn Spindle number (RRF 3.3 and later only)
Dn (Duet 3 MB6HC running RRF 3.4 or later only) SD slot number. The only value supported is 1.
En (RRF 3.5 and later only) LED strip number
C"name" Pin name(s) and optional inversion status
Qnn (optional) PWM frequency in Hz. 
Lbbb or Laaa:bbb (optional, for spindles only, RRF 3.3 and later)
Kaaa(:bbb[:ccc]) (optional, for spindles only, RRF 3.5 and later)

I just want an output pin to go to 5V when I send the command in Gcode. So I am not sure which type. Fans have speed and I don't need that... Heaters have PID or bang bang, but does that require a temp input? It's not exactly PWM, although it may be interesting to see if it could leverage PWM for the speed of the pump. It's not a spindle... gah... it's confusing...

Gumby

DIY-O-Sphere

@gumby
https://docs.duet3d.com/User_manual/Reference/Gcodes#m42-switch-io-pin

gumby

@DIY-O-Sphere

Thanks I will research it...

Gumby

gumby

@gumby

Just a quick note, I stumbled on the "pson" reference on IO4. I have not heard of this before so I dug around and found I can do exactly what I am trying to do by enabling the pson in the config file and now I have an on/off switch that is in the web interface. I can also control it via. M80 and M81 .

I am not declaring it a total victory yet, because I don't know if that snafus up something else in the process. But so far so good. Now I just have to figure out a way to incorporate it into my pre and post in my slicer when the time comes. I also want to make sure I have it working during filament changes/ hotend temps, etc.

Just thought it may help someone else as well.

Cheers,
Gumby