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Chapter 4 RS-232 And RS-422 Serial Interfaces
Data Carrier Detect (DCD). Status signal to the printer. The ON condition is
required for the printer to receive data.
Data Terminal Ready (DTR). Control signal from the printer. Subject to
configuration.
RS-422
+RD, -RD—Serial data stream differentially received by printer.
+TD, -TD—Differentially driven serial data stream for transmitting statu s and
control information to the host. Subject to protocol selection.
NOTE: ±RD and ±TD form signal and return paths of a d iff ere nti al li ne si gna l.
Table 12. RS-422 Serial Interface Connector Pin Assignments
Input Signals Output Signals Miscellaneous
Signal Pin Signal Pin Signal Pin
- Receive Data
(-RD) 15 - Transmit Data
(-TD) 19 Chassis Ground 1
+ Receive Data
(+RD) 17 + Transmit Data
(+TD) 25 Signal Ground 7