Hello - I looked at the wrong line in the dtab file earlier. The primary TMSCP address (where the TQK50 adaptor should go) is 174500. I accidentally gave the address of the first MSCP ('ra') earlier. So if you have both a TK50 and a TK25 the boards should be set like this TK25 172520 TK50 174500 Sorry for any confusion I caused. Steven