Hi,

I want to use the digitalRead() function to read pins of which I'm sending HIGH/LOW signals to.

I want to know which numbers the 18 pins on the right hand side of the board are?

I've attached an image of the RUMBA board that I'm using.

I'm using Marlin firmware.

Do I need to re-assign/re-name pins in pins.h or define new ones?

Many thanks

That's not a RUMBA board. That looks like a standard RAMPS 1.4 board that happens to be white. You can find the pin numbers here.