– 50 –
APPENDIX
20 mA current loop (option)Pin no. Signal name I/O Function
direction
9 TTY TXDR — Indicates the ground side of the data
signal of 20 mA loop current.
10 TTY TXD OUT Transmitted data of 20 mA current
loop.
17 TTY TXDR — Indicates the ground side of the data
signal of 20 mA loop current.
18 TTY RXDR — Indicates the ground side of the data
signal of 20 mA loop current.
19 TTY RXD IN Received data of 20 mA current loop.
23 TTY RXDR — Indicates the ground side of the data
signal at 20mA loop current.
24 TTY TXD OUT Transmission data of 20 mA current
loop.
25 TTY RXD IN Reception data of 20 mA current loop.
RS-422A (option)Pin no. Signal name I/O Function
direction
9 SD (+) OUT Transmitted data
10 SD (–) OUT Transmitted data
17 RD (+) IN Received data
18 RD (–) IN Received data
19 CS (+) IN When the host computer is set to standby
for data transmission, this signal
changes to “SPACE”.
(In this instance, the printer does not
check the signal.)
23 CS (–) IN When the host computer is set to standby
for data transmission, this signal
changes to “SPACE”.
(In this instance, the printer does not
check the signal.)
24 RS (+) OUT Data transmission request signal. When
the printer is ready to receive data, this
signal changes to “SPACE”.
25 RS (–) OUT Data transmission request signal. When
the printer is ready to receive data, this
signal changes to “SPACE”.
APPENDIX