A while back, [Matt] bought a few 8051 MCUs and tucked them away for a future project. He just found these fabulous little chips in a component drawer and decided it was time to figure these guys ...

The new Single-Wire On-chip Rapid Debugging (SWORD™) interface for the R8051XC2™ microcontroller core connects the 8051 to its debugging unit with just one IC debug port. The popular Joint Test Action ...