Azteeg X3 expansion pins to control a relay switch

I have the Azteeg X3 controller. Does anyone have more information on what the labels on the expansion pins mean? I would like to start experimenting with some of them to control this relay board:

Also, how would I go about doing that? What files would I need to modify (I have Sprinter firmware)? Can I create g-code commands that will switch a relay during a print?

Thanks for your help!!

The expansion pins correspond to different I/O pins (I believe they have the same pin layer as an arduino mega).

Here is the board layout [files.panucatt.com]

So under exp1 D25 = digital pin #25, under exp2 A5 = analog pin 5. This in mind if you know how to control pins on an arduino then you can do the same here.

As for g-code/firmware update you may not need to do anything special, and g-code M42 should work for what you need to do. M42 works like this

M42 P S for example I use the D04 pin located in the "low power switch" section of the X3 to turn on and off my driver cooling fan.
To turn on - M42 P04 S255
To turn off - M42 P04 S0
Since this is a pwm pin if I wanted to run the fans at part speed - M42 P04 S150

Hope this helps

Thanks @ikilledkenny !

That helps a lot. So, if I wanted to turn on a pin every time I called a certain tool/extruder, can you think of an easy way to insert the M42 command into every line of the g-code file where that tool is called? I am mainly thinking about two different extruders (T0 and T1) and when I switch between them I want to switch a few realys on or off.

Thanks again,

-Randall

Hi guys would you guys know were I can find the cover shiel expension with thermo couple drawing??

Thanks