Specifications

Operation Manual 3. Interface Specification
DR300 31
Pin Assignments
RS232C Interface Signals
PIN DIRECTION SIGNAL DESCRIPTION
1 Reference FG (Frame Ground)
2 To Host TD (Transmit Data) - Data from the printer to the host
computer. Sends X-On/X-Off characters or status data
(Bi-Directional protocol).
3 To Printer RD (Receive Data) - Data to the printer from the host
computer.
4 To Host RTS (Request to Send) Used with Ready/Busy flow
control to indicate an error condition. RTS is high and
remains high unless the print head is open, (in this case,
RTS would return to the high state after the print head is
closed and the printer is placed back on-line) or an error
condition occurs during printing (e.g., ribbon out, label
out).
5 To Printer CTS (Clear to Send) - When this line is high, the printer
assumes that data is ready to be transmitted. The prin-
ter will not receive data when this line is low. If this line
is not being used, it should be tied high (to pin 4).
6 To Printer DSR (Data Set Ready) - When this line is high, the prin-
ter will be ready to receive data. This line must be high
before data is transmitted. If this line is not being used,
itshouldbetiedhigh(topin20).
7 Reference SG (Signal Ground).
20 To Host DTR (Data Terminal Ready) - This signal applies to
Ready/Busy flow control. The printer is ready to receive
data when this pin is high. It goes low when the printer
is off-line, either manually or due to an error condition,
and while printing in the Single Job Buffer mode. It will
also go low when the data in the buffer reaches the Buf-
fer Near Full level.