IBM 6400 Series, Setup Manual

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RS-422
211
Receive Data (RD) . Serial data stream to the printer.
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.
Transmit 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.
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 status and
control information to the host. Subject to protocol selection.
NOTE:
±
RD and
±
TD form signal and return paths of a differential line signal.
RS-232 Serial Interface Protocols
DTR . (DTE Ready). The printer controls the data flow by asserting or de-
asserting this hardware signal to the host. If there is enough room in the
printer buffer, the printer will send a high signal; if the buffer is full the printer
will send a low signal. DTR tells the host if it is safe to send more data (If the
host sends data during an unsafe condition, data will be lost.
Table 6. 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