650 System Manual (Draft)
Version 0.4 August 20, 2008
18
Serial ports
The 650 has three external RS232 serial ports, two of which can be powered COM2 and
COM3. The serial ports are standard PC RS232 ports with a DB9 male connector. The
serial ports, in a normal configuration, are mapped to COM 1-3.
COM ports 2 and 3 can supply power to an external device when required, like the
optional J2 Customer Display. Voltage, +12, is supplied on pin 9 (RI) of the DB9
connector. The maximum current is 500ma and is over-current protected. To enable the
voltage supply for either COM ports 2 or 3 the BIOS setup must be changed. This
function can be enabled in the Advanced Settings screen under Super I/O Configuration.
COM1 also supports RS422 and 485 signaling. This can be enabled in the Advanced
Settings screen under Super I/O Configuration in the BIOS setup screen.
DB9 pin out serial ports
Pin RS232 RS422 RS485
1 DCD TXD- D-
2 RD RXD+
3 TD TXD+ D+
4 DTR RXD-
5 GND GND
6 DSR
7 RTS
8 CTS
9 RI
Serial Port