SMC Networks SpacePC 1232 Series User Manual
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Serial 2
Serial 1
J6
J5
Figure 12.
J5 and J6 Connectors layout
Both can be set as RS232 but only one (J5) can be set as RS422-485.
Refer to the following tables for the serial ports pinout assignment in RS232/422/485 modes.
Table 9.
J5, J6 Serial Port Connectors in RS232 mode
Pin Signal
Function
DB25
DB9
1
DCD
Data Carrier Detect
8
1
2
DSR
Data Set Ready
6
6
3
RX
Receive Data
3
2
4
RTS
Request To Send
4
7
5
TX
Transmit data
2
3
6
CTS
Clear To Send
5
8
7
DTR
Data Terminal
Ready
20
4
8
RI
Ring Indicator
22
9
9,10
GND
Signal Ground
7
5
Table 10.
J5 Serial Port Connector in RS422-RS485 modes
RS422
RS485
Pin
Signal
Function
In/out
Signal
Function
In/out
Pin
1
-TX
Transmit data
out
-TX/-RX
Transmit/Receive data
out/in
1
2
--
Not connected
--
--
Not connected
--
2
3
+TX
Transmit Data
out
+TX/+RX
Transmit/Receive data
out/in
3
4
--
Not connected
--
--
Not connected
--
4
5
-RX
Receive Data
in
--
Not connected
--
5
6
--
Not connected
--
--
Not connected
--
6
7
+RX
Receive Data
in
--
Not connected
--
7
8
--
Not connected
--
--
Not connected
--
8
9,10
gnd
Signal ground
--
gnd
Signal ground
--
9,10
Note. If the Serial port is used in RS485 mode, the bi-directional line must be controlled
via software, using the Data Terminal Ready (DTR) signal of the serial controller.
This signal is defined by bit 0 of the UART Modem Control Register (MCR) and the bi-
directional line is controlled as follows: