Processor Technology 3P+S, I/O
Processor Technology 3P+S, I/O rev A S-100 card 1976
(From the manual) 1.2.1 3P+S Description The 3P+S Input/Output Module is designed to meet all the I/O needs of most 8800 system users. For example, one teletype and two TV typewriters with keyboards can operate simultaneously with the 8800 through only one 3P+S. Similarly, one RS-232—C modem. a tele- type, and one TV typewriter plus another parallel data device can all be interfaced with one 3P+s at the same time. One parallel port is available to set up control conditions for both parallel and serial ports, as well as to set the serial I/O baud rate under program control. The baud rate can be set from 35 to 9600 Baud. Another parallel port allows polling the input data available flags and external device ready flags. This port also permits checking the serial I/O error flags. Full handshaking with both input and output peripherals can be implemented.