RS-232 and RS-422 Serial Interface Signals
RS-232 and RS-422 Serial Interface Signals
The
RS-232
Received Data (RD). Serial data stream to the printer.
Transmitted Data (TD). Serial data stream from the printer for transmitting status and control information to the host. Subject to protocol selection.
Request To Send (RTS). Control signal from the printer. Subject to configuration.
Clear To Send (CTS). Status signal to the printer indicating the host is ready to receive data/status signals from the printer.
Data Set Ready (DSR). Status signal to the printer indicating the host is in a ready condition.
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,
+TD,
NOTE: ±RD and ±TD form signal and return paths of a differential line signal.
RS-232 and RS-422 Serial Interface Protocol
XON/XOFF. The printer transmits an XON character (hex 11) when entering the online mode or when the buffer is almost empty. The printer transmits an XOFF character (hex 13) when entering the offline mode or when the buffer is almost full.
RS-232 and RS-422 Serial Interface Error Handling
NOTE: All serial errors are treated as faults that require operator intervention.
Parity Error Handling. Parity error checking is a configuration option selected from the control panel.
With odd or even parity checking selected, a character with a parity error is replaced with a question mark (?) character.
When parity checking is not selected (“NONE” on the control panel), parity errors are ignored and the characters are printed as received.
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