RS 232 interface

STOP BITS 0 1 Stop Bit 1.2 Stop Bits 1 Stop Bit if Word Length -8 Bits and Parity• 1Y, Stop Bits it Word Length - 5 Bits and No Panty WORD LENGTH 0 0 0 0 0 0 0 0 0 1 0101 0110 0111 1 0 0 0 1001 010 1011 BAUD RATE GENERATOR 18x EXTERNAL CLOCK 50 BAUD 75 109.92 134.5/3 150 300 600 1200 1800 2400 3800 BIT 65 LENGTH 008 0I7 106 115 RECEIVER CLOCK SOURCE 0 External Receiver Clock 1 = Baud Rate Generator This allows for 9-bit transmission 18 data bits plus parity) HARDWARE RESET PROGRAM RESET Signals at TTL level are sufficient to operate the modem and LSO5 buffers are therefore used. Complete address decoding of the 6551 is ensured by IC2and IC3so that only four locations in the memory are required, and these should be available on virtually any computer. 7-56 DATA WORD RS232 interface 0 0 CONTROL REGISTER This circuit is intended as an interface between the Elektor modem (Elektor, October 1984) and a computer. The software for each individual computer must, of course, be written sep...