Samsung SRP-275 Service Manual page 44

3-5-1(c) Cable Connection
PRINTER
SIDE
(25Pin)
3-5-1(d) Signal Description
Pin No. Signal name
Body Frame GND
2 TXD
3 RXD
6 DSR
7 Signal GND
20 DTR
3-5-1(e) H/W Flow Control
When DTR/DSR flow control is select, before transmitting a data, the Printer checks whether the host is
BUSY or not. If the host is BUSY, the Printer does not transmit a data to the host. If the host is not BUSY, the
Printer transmits a data to the Host. The host is the same.
3-5-1(f) S/W Flow Control
When XON/XOFF flow control is selected, the printer transmits XON(ASCII 11h) or XOFF(ASCII 13h) signal
through the TXD line. If the printer is busy, the printer transmits XOFF(ASCII 13h) to host through the TXD
line. Then the host recognize that the printer is busy. So, the host does not transmit a data to the printer. If
printer is released from busy, the printer transmits XON(ASCII 11h) to host through the TXD line. Then the
host recognize that the printer is not busy. And the host transmit a data to the printer.
Rev. 2.00
(F.G) 1
(TXD) 2
(RXD) 3
(RTS) 4
(CTS) 5
(DSR) 6
(S.G) 7
(DTR) 20
Signal direction Function
- Frame ground
Output Transmit data
Input Receive data
This signal indicates whether the host computer can receive
data. (H/W flow control)
MARK(Logic 1) : The host can not receive a data.
①
SPACE(Logic 0) : The host can receive a da
②
Input
The printer transmits a data to the host, after confirming
③
this signal.
When XON/XOFF flow control is selected, the printer
④
does not check this signal.
- Signal ground
This signal indicates whether the printer is busy.
(H/W flow control)
MARK(Logic 1) : The printer is busy.
①
SPACE(Logic 0) : The printer is not busy.
②
Output
The host transmits a data to the printer, after confirming
③
this signal.
When XON/XOFF flow control is selected, the host does
④
not check this signal.
1 (F.G)
2 (RXD)
3 (TXD)
4 (DTR)
5 (S.G)
6 (DSR)
7 (RTS)
8 (CTS)
- 44 -
SRP-275
HOST
SIDE
(9Pin)
ta.