Epson TM-U925 Manual page 24

3) Interface connector terminal assignments and signal functions are described in Table 2.1.1.
Pin number Signal name
1 FG
2 TXD
3 RXD
4 RTS
6 DSR
7 SG
20 DTR
EPSON
Table 2.1.1 TM-U925 Printer Status and Signals
Signal direction
--
Frame ground
Output
Transmit data
Input
Receive data
Output
DIP SW 1-6 OFF: Same as DTR signal (Pin 20)
DIP SW 1-6 ON:
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 when transmitting data by
GS ENQ, DLE ENQ, and GS a).
When XON/XOFF control is selected, the printer does not
check this signal.
Changing the DIP switch setting enables this signal to be used
as a reset signal for the printer (refer to Section 3.3.3).
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 DIP SW 2-5 as follows (refer to Section 3.3.3):
1. During the period from when the
power is turned on (including
resetting using the interface) to
when the printer is ready to
receive data.
2. During the self-test.
3. When the cover is open.
4. During paper feeding using the
PAPER FEED button.
5. When the printer stops printing
due to a paper-end.
6. When an error has occurred.
7. When the receive buffer
becomes full.(*)
TITLE
TM-U925
Specification
(STANDARD)
Function
Logical product of DTR signals of DM-D
and TM (If both are SPACE, the printer can
receive data (SPACE).)
Printer status
SHEET
REVISION
A
DIP SW 2-5 status
ON OFF
BUSY BUSY
BUSY BUSY
-- BUSY
-- BUSY
-- BUSY
-- BUSY
BUSY
NO.
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