Ok, got the jumpers in on the other ports and the board now responds to the M115 command, although the address it responds to is the old one I had set when I was using the board previously. I thought the hardware reset was supposed to reset the address back to 121. The procedure for toolboard reset is to hold both buttons down on power on, correct? Is there a requirement for how long the buttons should be pressed?
Anyways, this looks like I have some more testing to do to see if I can get the new board reconfigured now that I know its working. If it stops working if I move it back to the correct port then I know to replace the distribution board.
Thanks for the help, you got me a little further down the road...