User`s manual

Functional Description 43
cPCI-3920
Universal Serial Ports
Two PC-compatible serial RS-232, 9-pin D-Sub ports are avail-
able and fully compatible with the 16C550 controller. These port
includes a complete set of handshaking and modem control sig-
nals. Data transfer rates up to 115.2 kB/s are supported.
The COM3 interface is routed to the connector CN1.
COM3 DB-9 Serial Port Connector (CN1)
Table 3-11: COM3 Serial Port Connector Pin Definition
The COM4 interface is routed to the connector CN6-2. The COM4
interface supports RS-232/422/485/485+.
COM4 DB-9 Serial Port Connector (CN6-2)
Table 3-12: COM4 Serial Port Connector Pin Definition
Pin # RS-232
1 DCD, Data carrier detect
2 RXD, Receive data
3 TXD, Transmit data
4 DTR, Data terminal ready
5 GND, Ground
6 DSR, Data set ready
7 RTS, Request to send
8 CTS, Clear to send
9 RI, Ring indicator
Pin # RS-232 RS422/485+ RS485
1 DCD, Data carrier detect TXD- Data-
2 RXD, Receive data TXD+ Data+
3 TXD, Transmit data RXD+ --
4 DTR, Data terminal ready RXD --
5 IsoGND, Isolated ground GND GND
6 DSR, Data set ready -- --
7 RTS, Request to send -- --
8 CTS, Clear to send -- --
9 RI, Ring indicator -- --