Troubleshooting The Rs-422; Lead Polarities - Genicom 5050 User Manual

5050/5100 User's Manual

Troubleshooting the RS-422

For the RS-422 interface to perform, the interface must be selected
from the Serial Type Menu located under the Set Up menu. The baud
rate, character frame, and Ready/Busy protocol (usually XON/XOFF)
at the printer must match those of the host.
Host Printer
TX-A RX-A
TX-B RX-B
RX-A TX-A
RX-B TX-B

Lead Polarities

The polarity indicators, -A and -B, are defined by the EIA
specifications. -A is negative with respect to -B in the mark (logic 1)
state.
Some vendors designate RS-422 polarities with a plus or minus sign
rather than -A and -B without a consensis to their meanings. If
polarities are reversed, then (readable) data will not be exchanged;
however, no damage will result.
Printer Pin
15
17
19
25
198
GEK-99044E