For long-term voyaging, I intend to use laptop based chartplotting for route planning, electronic charts and so on in addition to both a simple plotter and paper charts where necessary. To this end, I bought yesterday a Holux GR-213 USB GPS antenna. It's a SIRF III chipset with WAAS option that outputs NMEA 183 strings, and it loaded readily onto my Dell Inspirion 8200, a late 2003 laptop that runs XP SP2, and is not only "surplus to my needs", but carries two batteries, giving it about seven hours of runtime.
The Holux auto-configured itself to "virtual" port COM 4, and its rudimentary "GPS Viewer" utility acquired surprisingly rapidly and accurately. I was walking around the backyard (the lat/lon of which I know) and it works fine.
I had hoped to test SeaClear II with the free American ENC charts for Lake Ontario, but SeaClear "can not open COM 4", and no amount of fiddling seems to help. Suspecting it needed a nine-pin serial port connector, I loaded a utility called Prolific USB-to-Serial Port Emulator, which reassigned the GPS to COM 2. Again, Seaclear couldn't "see" the NMEA information.
First off, SeaClear II only works with RASTER charts in the BSB format. It does not work with ENC charts at all.
I am at an intermediate to advanced level of skills with Windows, and I tried various fixes with port settings under Device Manager, with no luck. I can get the GPS to work and to supply lat/lon...but not to SeaClear.
I seek three bits of advice, therefore:
1) Would a USB-to-serial port dongle or connector work here, and if so, what brand or type has the proper pin set-up (1, 5, 9 or something...)
There is no USB-to-Serial adapter that allows you to use a USB-device on a RS-232 serial port AFAIK
... There is very little market or demand for such a device and one has not been made commercially AFAIK
2) Does anyone know a patch or fix or technique to get SeaClear to read the output from any USB GPS or just this one? There is no Holux "USB to serial emulator" utility to my knowledge.
There might be a software driver that will allow you to emulate a serial port for the USB device's output, but I don't know of any such software. You might try looking here
for the software you require.
3) I don't have to use SeaClear, as this is simply at the testing stage of PC chartplotting. Is there a free navigation package that can run free downloadable charts and will recognize USB GPS NMEA input? It doesn't have to be good in terms of design, but I want to go out in the old boat before haulout and see how practical this is.
Your help is appreciated. I know SeaClear is popular, free and, while quirky, displays well and has rich features. I also know it's completely unsupported by its programmer, so I'm not going that route.
There are no free chartplotting packages that support ENC charts AFAIK
. There are quite a few that support the older BSB format charts.