Printronix L5520 - Manual (Page 223)

RS-422 Serial Interface
223
RS-422 Serial Interface Signals
The RS-422 serial interface signals are defined below:
• Received Data (RxD) - Serial data stream from the host to the
printer.
• Transmitted Data (TxD) - Serial data stream from the printer to
the host. Subject to protocol selection.
• Request To Send (RTS) - Control signal from the printer to
request permission to send data to the host. 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.
When CTS is enabled, DSR and CTS must both be asserted
for the printer to transmit flow control characters to the host.
• Data Set Ready (DSR) / Clock B - Status signal to the printer
indicating the host is in a ready condition. DSR is ignored
unless CTS is enabled.
• Data Terminal Ready (DTR) - Control signal from the printer to
the host. When enabled, the host activates the data channel.
Subject to configuration.
• Clock Signal B - External timing for signals on data channel B.