Functions Of Each Connector Pin - Epson TM L90 Technical Reference Manual

A.1.2 Functions of each connector pin
Signal
Pin no. name
1 FG
2 TXD
3 RXD
4 RTS
6 DSR
7 SG
20 DTR
25 INIT
A-2 Interface And Connectors
Signal
direction Function
- Frame ground
Output Transfer data
Input Reception data
Output Memory Switch Msw 1-6 OFF: Same as DTR signal (Pin 20)
Memory Switch Msw 1-6 ON: Logical product of DTR signals of DM-D and TM
Input This signal indicates whether the host computer can receive data.
SPACE indicates that the host computer can receive data, and MARK indicates
that the host computer cannot receive data.
When DTR/DSR control is selected, the printer transmits data after confirming this
signal.(Except as transmitted using some ESC/POS commands)
When XON/XOFF control is selected, the printer does not check this signal.
Changing the memory switch 1-7 setting enables this signal to be used as a reset
signal for the printer.
The printer is reset when the signal remains MARK for 1 ms or more.
- Signal ground
Output 1) When DTR/DSR control is selected, this signal indicates whether the printer is
busy. SPACE indicates that the printer is ready to receive data, and MARK
indicates that the printer is busy. The busy condition can be changed by using
memory switch 1-3. (Refer to "Busy state" on page 4-9)
2) When XON/XOFF control is selected:
The signal indicates whether the printer is correctly connected and is ready to
receive data. SPACE indicates that the printer is ready to receive data. The
signal is always SPACE except in the following cases:
• During the period from when the power is turned on to when the printer is
ready to receive data.
• During the self test
Input Changing the memory switch 1-8 setting enables this signal to be used as a reset
signal for the printer.
The printer is reset when the signal remains SPACE for 1 ms or more.
(If both are SPACE, the printer can receive data
(SPACE).)
Rev. B