Hi, I'm a newbie CNC'er using my 2418 Chinese machine and I'm trying to

Hi, I’m a newbie CNC’er using my 2418 Chinese machine and I’m trying to get the probing / levelling feature to work for pcb etching. I’m uncertain of the connection required on the bespoke Arduino board, can anyone advise .Hopefully the picture is shown below of the board…other connections are hidden by the stepper motor driver boards. Many thanks. Paul

Could not find the pinout for your Board, but if it is based on arduino A5 would be the probe pin.