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CN4 – USB Connector
GPS can be connected to a CPU USB port. The NovAtel module will appear as three COM ports
to the system.
Pin Name
Description
1
Vcc
USB Power Input
(Does not power NovAtel Receiver)
2 n/c
No
connect
3
D-
USB Data -
4 n/c
No
connect
5
D+
USB Data +
6 n/c
No
connect
7 GND
No
connect
8 GND
No
connect
9 Shield
Shield
10 Shield Shield
Note on using RS-422 or RS-485 Mode
When using the serial port in RS-422 or RS-485 mode, the serial transmitters are enabled and
disabled under software control. The transmitters are enabled by manipulating the Request To
Send (RTS*) signal of the first serial port controller. This signal is controlled by writing bit 1 of the
Modem Control Register (MCR) as follows:
•
If MCR bit 1 = 1, then RTS* = 0, and serial transmitters are disabled
•
If MCR bit 1 = 0, then RTS* = 1, and serial transmitters are enabled
For more information on the serial port registers, including the MCR, please refer to a standard
PC-AT hardware reference for the 16550-type UART.
