232SPS2-3903 Manual
Appendix B: Serial Port Connections
B-3
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5104
* When using XON/XOFF control, this connection may not be
required.
** Some systems may require this connection.
* When using XON/XOFF control, this connection may not be
required.
** Some systems may require this connection.
TABLE B-1
DB-25 Serial Port Connections (S to P)
Serial Port
(DTE)
DB-25S Pin #
Signal Name
Direction
232SPS2
(DCE)
DB-25P Pin#
2 Transmit
Data -----------> 2
3 Receive
Data <----------- 3
4 Request
to
Send
4
5
Clear to Send
<-----------
5**
6
Data Set Ready
<-----------
6**
7 Signal
Ground
7
8 Carrier
Detect <----------- 8**
20
Data Terminal Ready ----------->
20
22 Ring
Indicator
NC
TABLE B-2
DB-9 Serial Port Connections (S to P)
Serial Port
(DTE)
DB-9S Pin#
Signal Name
Direction
232SPS2
(DCE)
DB-25P Pin#
1
Data Carrier Detect <-----------
8**
2 Receive
Data <----------- 3
3 Transmit
Data
-----------> 2
4 Data
Terminal
Ready
-----------> 20
5 Signal
Ground
7
6
Data Set Ready
<-----------
6**
7 Request
to
Send
4
8 Clear
to
Send
<----------- 5**
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Appendix B: Serial Port Connections
232SPS2-3903 Manual
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5104
PARALLEL TO SERIAL MODE, HARDWARE HANDSHAKING
The serial port of the 232SPS2 module is wired as a DCE
device. For proper operation the following connections must be
present:
1. Transmit Data (TD) from the printer (DTE) must be
connected to Pin #2 on the 232SPS2 module.
2. Data Set Ready (DSR) from the printer must be
connected to Pin #6 on the 232SPS2 module.
3. Signal Ground (SG) from the printer must be
connected to Pin #7 on the 232SPS2 module.
If port powering the 232SPS2, these connections are
recommended:
4. Request to Send (RTS) from the host must be
connected to Pin #4 on the 232SPS2 module.
5. Data Terminal Ready (DTR) from the host must be
connected to Pin #20 on the 232SPS2 module.
Some printers may require one or more of the following connections:
6. Clear To Send (CTS) from the printer should be
connected to Pin #5 on the 232SPS2 module.
7. Data Carrier Detect (DCD) from the printer should
be connected to Pin #8 on the 232SPS2 module.
NOTE: IBM PC’s (or compatible) serial ports and serial printers are
both DTE devices. Therefore, a null modem cable (like a serial
printer cable!) must be used when connecting a PC’s serial port to
a printer. A null modem cable or serial printer cable should not be
used to connect to the 232SPS2 (unless your device is a DCE --
such as a modem).
PARALLEL TO SERIAL MODE, SOFTWARE HANDSHAKING
For proper operation the following connections must be present:
1. Transmit Data (TD) from the printer (DTE) must be
connected to Pin #2 on the 232SPS2 module.
2. Receive (RD) from the printer must be connected to
Pin #3 on the 232SPS2 module.
3. Signal Ground (SG) from the printer must be
connected to Pin #7 on the 232SPS2 module.
If port powering the 232SPS2, these connections are
recommended:
4. Request to Send (RTS) from the host must be
connected to Pin #4 on the 232SPS2 module.
5. Data Terminal Ready (DTR) from the host must be
connected to Pin #20 on the 232SPS2 module.
