Perhaps if you post the make and model of the treadmill somebody can dig an explanation for you.

 

Perhaps if you post the make and model of the treadmill somebody can dig an explanation for you.

Unfortunately I had a ToorX treadmill that had damaged Control Board first then Motor Control Board, then I replaced the Motor Board with the one you see in the photos...is a clone of Sole F63 Board or Z700-A82 treadmill etc... The comunication with the upper Control Board (which I dont have and want to replace with an arduino board) comunicates with the "many pin port" that I show in the draw of the second photo with the 12 pins port