Woodie@MIT-MULTICS.ARPA (Paul E. Woodie) (10/07/85)
Although I have not checked it out, I assume that the overlays for the MEX (and perhaps a few other ) modem program(s) for the O1 have the assembly code for implementing a "break" using the uart chip in the O1. These overlays can be found in the simtel20 archives: micro:<cpm.mex>. --Paul Woodie