Question Better documentation for external Sub-D 15 signal

Stepcraft has very good instructions when it comes to the building of the machine. But when it comes to using external diy devices I find the official support lacking. I can only see the pinout of the D 15 connector but no additional information on the usage or limits of the connectors. Some tutorials and better documentation would be very helpful to users in extending the capabilities of the machine.

I believe that there are a lot of information in the deutsch part of the forum but it makes finding information much slower and using online translation can lead to mistakes, and I don't want to fry the stepcraft board because I made a mistake.

I guess that in the simplest application you just use the pin2 (gnd) and pin13/14 (relay1&2) but there are some connectors I have no idea what they do and why there are multiples of some pins (6 and 14 are both marked relay2)?

Any luck finding more documentation about the external connector? I am looking into making a dispensing robot, just simple on/off at the right timestamps. Do you have any suggestions about electrical connections and/or control software?

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Actually you have the possibility to control 3 relay ports from within the software.
PIN 6, 13 and 14. There is just a writing error regarding PIN 14 which is actually Relay 3.
Normally you can control those PINS by GCode like:
M03 which is starting Relay 1 (usually the Spindle),
M05 Relay 1 off
M07 Relay 3 on (Typically used for the cooling fluid)
M08 Relay 2 on (typically used for the vacuum cleaner)
M09 Relay 2 and 3 off