84
Functions of each connector pin
Pin no.
Signal name
Signal direction
Function
1
FG
—
Frame ground
2
TXD
Output
Transmission data
3
RXD
Input
Reception data
4
RTS
Output
Equivalent to DTR signal (pin 20)
6
DSR
Input
This signal indicates whether the host computer can
receive data.
SPACE indicates that the host computer can receive
data. MARK indicates that the host computer
cannot receive data.
When DTR/DSR control is selected, the printer
transmits data after confirming this signal (except if
transmitted using some ESC/POS commands).
When XON/XOFF control is selected, the printer does
not check this signal.
Changing DIP switch 2-7 lets this signal be used as a
printer reset signal.
When you use this signal as the printer’s reset signal,
the printer is reset when the signal remains MARK for
a pulse width of 1 ms or more.
7
SG
—
Signal ground
20
DTR
Output
1) When DTR/DSR control is selected, this signal
indicates whether the printer is BUSY.
•
SPACE status
Indicates that the printer is ready to receive data.
•
MARK status
Indicates that the printer is BUSY. Set BUSY conditions
with DIP switch 2-1.
2) When XON/XOFF control is selected, the signal
indicates that the printer is properly connected and
ready to receive data from the host. The signal is
always SPACE, except in the following cases:
•
During the period from when power is turned on to
when the printer is ready to receive data.
•
During the self-test.
25
INT
Input
Changing DIP switch 2-8 enables this signal to be
used as a reset signal for the printer. The printer is
reset if the signal remains at SPACE for a pulse width
of 1 ms or more.