Owner's Manual

Signal level
Mark (1) -3 V to -27 V
Space (0) +3 V to +27 V
Handshaking
Handshaking by DTR signal or X-on/X-off. The DTR signal changes
to mark-meaning the printer is not ready to receive data-when
the number of bytes free in the input buffer goes down to 256. The
signal changes to space-meaning that the printer is now ready-
when the number of bytes in the input buffer rises to 528.
Error handling
A * character is printed if a parity error is detected. All other errors
are ignored.
Connector
D-sub 25-pin connector
In this table, the direction of signals is given relative to the printer.
Pin
Signal
number Signal direction
Direction
2
TXD
out
Transmits data for X-on/X-off
20 DTR
out
Indicates whether or not the printer is ready
to receive data. "Mark" level indicates
printer is not ready to receive data.
3
RXD
in
Receives data
11
REV
out
Same as DTR
(=2nd RTS)
7
SG
-----
Signal (logic) ground level
1 CG
-----
Printer chassis ground
Technical Specifications 8-15