Identifying GPIO pins and assigning to cnc shield v3

Okay, so I’m making good progress on Grbl-Esp32, with help have successfully compiled and run code on a Wemos R1 D32 with attached cnc shield v3.

However, I am totally in the dark as to which gpio pin referenced in the Machine.h file corresponds to the pin on the shield.
The cpumap.h file no longer contains the info.
I KNOW, because I have seen the code that GPIO pin 17 corresponds to the Z+ endstop pin on the right hand side of the board, but there are no indications as to:

  1. which pin is which on the shield and
  2. what pins, by number, are suitable for assigning say a relay to, or utilising the A axis as a clone of Y.

Hope someone can clear this up as I cannot find any clear resource on the web.

many thanks.

Do you have a link to information on the board you bought?

There is usually a pin map available for esp32 modules, and then you can “buzz out” at least most of the connections from the module to places on the board with a multimeter set to continuity mode.

Hi Michael, here is a link to the Wemos and the shield is a Protoneer cnc shield v3

Many thanks,

Link to the shield while you are at it?

Apologies Michael.
The board in the link is the same as the one I bought but I suspect a Chinese copy.

many thanks.

Well, solectroshop doesn’t seem to host the pinout, but with a search I found this: Wemos® D1 R32 w/ ESP32 UNO R3 pinout

The corresponding arduino pinout for comparison:

Here is the arduino pin assignment as routed on the shield:


Those taken together should show you how to work out mapping pins to assignments.

Many thanks Michael.

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