User`s manual

12 Hardware Information
PXI-3920/3910
User’s Manual
2.4.6 COM Ports
The PXI-3920/3910 provides two COM ports on the faceplate
in D-sub 9P connectors. These two serial ports are 16C550
UART compatible and support RS-232/RS-422/RS-485 by
jumper selection. Please refer to section 2.6.2 for setting the
COM ports.
Figure 2-6: COM Ports & Pin Assignments
Signal Name
PIN
RS-232 RS-422 RS-485
1 DCD# TXD422- 485DATA-
2 RXD# TXD422+ 485DATA+
3 TXD# RXD422+
4 DTR# RXD422-
5 GND
6 DSR#
7 RTS#
8 CTS#
9 RI#