I just picked up for a song, an old but working Magellan NAV 5200DX GPS unit; built like a tank, but no longer supported. I have the manual but no NMEA data cables. I know the four wire colours in the proprietary-plug NMEA data cable that connect to the next piece of gear (VHF, PC, chart plotter, or whatever) - blue is NMEA + (data out), and red is data ground. Black (+) and white (-) connect to a Differential Beacon Receiver (DBR) for more accurate position data; probably unobtainable even on eBay. And likely not of significant benefit. I would like to connect to a VHF, and possibly a PC in the future.
What I don't have, and no info is available in any manual or from extensive Google searches,

is the pin out for the two (identical) six pin Data port sockets at the back of the unit. I'm wondering if anyone has one of these cables, would you mind identifying which of each of the four wires goes to which pin of the plug?
The ports on the unit accept a six pin proprietary plug and the ports look like this, looking at the back of the unit:
.....x*..( )..x
..x...............x
.......x.....x
the x is a socket, the asterisk represents a raised marker at one socket - for pin 1?, and there is a crescent cut out at the top, which I've shown as () - between that socket and the one next to it; the dots are just spacers. I believe two of the pins are unused.
I like the data displayed on this unit, even though it is
very old - the first nav screen for instance shows COG and SOG, cross track error, and bearing and distance to waypoint. I feel that using this GPS, with all its capabilities and features,
together with paper charts, I will learn more about piloting and navigation than a chart plotter could ever teach me.
So that's my plea: if you have a NAV 5200DX, or just know the answer, could you please tell me the NMEA data cable pin out? All assistance greatly appreciated