This is pretty similar to hardware made by Radical Software and Accolade for professional development back in the day. Also the EA dev hardware was similar but

This is pretty similar to hardware made by Radical Software and Accolade for professional development back in the day. Also the EA dev hardware was similar but more advanced since it contained additional hardware for capturing the bus like a logic analyzer might. For the Accolade version it was very similar to this design. I worked on the debugger and it was a lot of fun. At the time we used the Lattice C compiler and I supported C source level debugging including watches that could use a C like parser.