I'll have to see if the RS232 pack uses 1488/1489 or MAX (I assume the former, given the age and the fact that they are Moto ICs). Maybe that is the reason. Maybe it's time for a nice new RS232 pack, using a CMOS 65C51 that does not have the bug, and using the method in the Turbo232 to do 230Kbps on the 65C51. It works fine. Jim