Raymarine Marine GPS System - Manual (Page 178)

RayTech Navigator User’s Guide
A-14
To wire an RS-232 device to provide input to an NMEA device:
1. Connect the RS-232 Device’s Tx lead to the NMEA
Device’s Rx+ lead.
2. Connect the RS-232 Device’s SGnd lead to the NMEA
Device’s Rx- lead.
To wire an RS-232 device to receive input from an NMEA device:
1. Connect the RS-232 Device’s Rx lead to the NMEA
Device’s Tx+ lead.
2. Connect the RS-232 Device’s SGnd lead to the NMEA
Device’s Tx- lead.
To wire an RS-232 device to provide input to and receive input from
an NMEA device:
1. Connect the RS-232 Device’s Tx lead to the NMEA
Device’s Rx+ lead.
2. Connect the RS-232 Device’s Rx lead to the NMEA
Device’s Tx+ lead.
3. Connect the RS-232 Device’s SGnd lead to the NMEA
Device’s Tx- and Rx- leads.
There are some infrequent cases where binding the NMEA device’s
Tx- and Rx- leads together may cause difficulties. If you do encounter
problems, you’ll need to use an RS-232-to-NMEA converter between
the two devices. A converter is typically required very rarely (in less
than 1% of applications; however, the modern Furuno radar systems,
for example, do require them), but is still a good place to begin trouble-
shooting if problems arise with the RS-232/NMEA interconnection.