C-Maps data input ?

[capt_birdseye]

A colleague is wanting to use his laptop and C-Maps for navigation.
Is this possible, and how would we set-up ( Configure ) the data input from his hand held GPS to the Laptop please ?
He is ditching his very old Livecharts.
Thanks in advance !

 

[Gordonmc]

Making a PC to GPS Connection: The serial port on most portable PC’s is the male nine pin socket at the back of the computer. Only two of the nine pins are used for the GPS connection, No. 2 is for data out of the PC, N0 3 is for NMEA data in to the PC (look at a nine pin plug with your best reading glasses on and they will usually be marked in tiny letters).

These two pins are connected to the NMEA In and NMEA Out wires from your GPS (look at your GPS manual, and there will be instructions on how to find these). Larger GPS have dedicated outputs to run Yeoman plotters, electronic charts and so on, but even handheld GPS have an accessory to plug in to give you a NMEA feed. You often need to configure the GPS to send an NMEA signal down the wire you will be connecting to your PC. Have a look in the GPS manual.

The easiest way to make a lead to connect your GPS to your computer is to buy a computer cable of any type that had a female nine pin plug on the end. You can even use an old mouse or other cable, provided it has a plug which fits the back of the PC. Chop off the cable to a suitable length, identify pins two and three using the continuity tester on your electrical meter, and splice in the wires to the feed from your GPS. Some GPS will advise you to also connect a ground or earth pin from the GPS to the computer

Troubleshooting your GPS/PC Interface: You can “see” a GPS signal using your electrical meter, so you will know if you have a live plug with the correct connections. Set you electrical meter to read something under 10v DC, and check the plug connections. A GPS signal looks like “Positive volts…No volts…Positive volts…No Volts…Positive volts…No volts…..” at about half second intervals. If you have an external GPS aerial, these are usually stand alone GPS engines – all you need is to apply power, and they will give you an NMEA signal with position, handy if your expensive interface packs up.

The next way to check your GPS signal is to use the “Hyperterminal” facility on your pc. (found under Start – Programs – Communications – Hyperterminal). Create a new connection (choose an icon and a name). Make sure you select “connect using Com 1” – the nine pin plug on the back of your pc. Hyperterminal will usually automatically sense the type of signal it receives - if you have to set it manually, the format is normally 4,800 baud, 8 bits, no parity, one stop bit. When you connect, you will see string of characters which look like this:

$IIRMC,230316,A,1636.992,S,15133.741,W,0.00,0,100801,12,E*67

If you do, you have got a good NMEA signal!

 

[capt_birdseye]

Many thanks for the quick reply.
Something to try tonight.
Regards,
BWM.

 

[Oldhand]

Won't work without connecting RS232 pin 5 to the NMEA return line, will it? /forums/images/graemlins/confused.gif