Kontron JRexplus-DC - Manual (Page 25)

KTD-S0008-F Page 20 Serial Port Interfaces
JRexplus-DC User's Guide
8 Serial Port Interfaces
Two fully functional serial ports (COMA and COMB) provide asynchronous serial communications. COMA and
COMB support RS-232 operation modes. They are 16550 high-speed UART compatible and support 16-byte
FIFO buffers for transfer rates from 50 Baud to 115.2 kBaud. A programmable baud rate generator allows
transfer rates up to 1 MBaud.
One serial port is available as RS-232 on the JRex front panel and can be used as well as RS-422 or RS-485
interface, the second serial port COMB is available through a 10 pin header.
8.1 Connectors
COMA is available through the standard DSUB9 connector J28 (9 pins).
Header Pin Signal Name Function DSUB25
1 /DCD Data carrier detect 8
2 RXD Receive data 3
3 TXD Transmit data 2
4 /DTR Data terminal ready 20
5 GND Ground 7
6 /DSR Data set ready 6
7 /RTS Request to send 4
8 /CTS Clear to send 5
1
5
9
6
9 /RI Ring indicator 22
The same connector J28 can be used as a RS-422 or RS-485 interface. The configuration is changeable in
the BIOS Setup.
Header Pin RS-422 RS-485 Function
1 TX- TX- / RX- Transmit data - / Receive data -
2 N.C. N.C. Not connected
3 TX+ TX+ / RX+ Transmit data + / Receive data +
4 N.C. N.C. Not connected
5 GND GND Ground
6 RX+ N.C. Receive data + / Not connected
7 N.C. N.C. Not connected
8 RX- N.C. Receive data - / Not connected
1
5
9
6
9 N.C. N.C. Not connected
Attention: A RS-422/RS-485 terminating resistor is not equipped on the JRexplus-DC.