+D0T-C0M Posted March 24, 2005 Share Posted March 24, 2005 (edited) I was just wondering if the new explorist 400,500, and 600 were NEMA compatible because they won't have a serial port (only USB) and I believe NEMA is a serial protocol. I don't have a serial port on my laptop and I was actually using my Sportrak in NEMA mode through a USB to serial adapter so that I can track on my laptop in realtime. So I guess I'm asking, Will the new explorist be able to use the USB port to transmit the NEMA protocol? EDIT changed NEMA to NMEA Edited March 25, 2005 by D0T-C0M Quote Link to comment
Dale_Lynn Posted March 24, 2005 Share Posted March 24, 2005 (edited) Do you really mean NMEA mode? I would think if PC has USB ports , and GPS is designed for USB connection, MNEA protocol is a non-issue..... This site shouldl give you more information on what NMEA is all about... http://www.gpsinformation.org/dale/nmea.htm I actually have NEMA mode turned off on my Magelllen Meridian and dont see any difference in "communications".... Dale Edited March 24, 2005 by Dale_Lynn Quote Link to comment
+Renegade Knight Posted March 24, 2005 Share Posted March 24, 2005 It's a serial protocal. If it can send it via USB and the USB can be convirted to Serial it could work. But I don't know if the Explorist supports it at all. Quote Link to comment
+Stunod Posted March 24, 2005 Share Posted March 24, 2005 How do the USB Garmins work? Anyone know? I would assume you would need software running on the PC to convert the USB signal to NEMA protocol. Quote Link to comment
+Stunod Posted March 24, 2005 Share Posted March 24, 2005 Do you really mean NMEA mode? I would think if PC has USB ports , and GPS is designed for USB connection, MNEA protocol is a non-issue..... This site shouldl give you more information on what NMEA is all about... http://www.gpsinformation.org/dale/nmea.htm I actually have NEMA mode turned off on my Magelllen Meridian and dont see any difference in "communications".... Dale The NEMA mode is used to send current position information to other devices, not for up/downloading waypoint or tracks. So, if you want to connect your GPS to a laptop and track live on mapping software, you will need a NEMA connection. Quote Link to comment
Dale_Lynn Posted March 24, 2005 Share Posted March 24, 2005 (edited) The NEMA mode is used to send current position information to other devices, not for up/downloading waypoint or tracks. So, if you want to connect your GPS to a laptop and track live on mapping software, you will need a NEMA connection. I kind of came to the same conclusion after reading more about NMEA and thinking the processes through after my inital post. Dale Edited March 24, 2005 by Dale_Lynn Quote Link to comment
+Jamie Z Posted March 24, 2005 Share Posted March 24, 2005 How do the USB Garmins work? Anyone know? I understand the Garmin units have both. You can plug USB into the unit, but it also has a connection for a serial cable. I'm not 100% sure, but I have read that somewhere on the forums. Jamie Quote Link to comment
reidster Posted March 24, 2005 Share Posted March 24, 2005 How do the USB Garmins work? Anyone know? I understand the Garmin units have both. You can plug USB into the unit, but it also has a connection for a serial cable. After reading the manuals (I don't own a Garmin and never will - see below), the newer color units have a USB serial I/O port. The older, non-"C", units just have an RS232 interface. Note: The RS232 units list NMEA 0183 protocol as an option. The newer ones list their interface as only "Garmin Proprietary"! Also they only mention using the port for use with their mapping programs. Unless others reverse-engineer their protocol (and proprietary usually means you legally can't), it seems many third-party applications will no longer work. Quote Link to comment
+Cornix Posted March 24, 2005 Share Posted March 24, 2005 How do the USB Garmins work? Anyone know? The high end models (60 C/CS, 76 C/CS) have both USB and serial ports and support NMEA. The new Vista C and Legend C only have USB. Garmin GPS goes (more) proprietarySimon St. Laurent Garmin's most recent outdoor GPS units sport a USB port instead of the strange proprietary connector they used to have. That sounds great, except that Garmin's gone more proprietary on the protocol they use to send location data over that connection, abandoning NMEA in favor of Garmin's own protocol - exclusively. ... Source: O'Reilly Weblogs However there seems to be a solution: You can try Franson GpsGate 1.10. It solves this problem. It creates a number of virtual serial ports old GPS applications can connect to, and convert the Garmin protocol to NMEA. You can in fact connect any number of GPS applications to the GPS at the same time. http://franson.biz/gpsgate/guide.asp?section=Garmin_Usb_Gps Cornix Quote Link to comment
rickertk Posted March 24, 2005 Share Posted March 24, 2005 How do the USB Garmins work? Anyone know? I understand the Garmin units have both. You can plug USB into the unit, but it also has a connection for a serial cable. After reading the manuals (I don't own a Garmin and never will - see below), the newer color units have a USB serial I/O port. The older, non-"C", units just have an RS232 interface. Note: The RS232 units list NMEA 0183 protocol as an option. The newer ones list their interface as only "Garmin Proprietary"! Also they only mention using the port for use with their mapping programs. Unless others reverse-engineer their protocol (and proprietary usually means you legally can't), it seems many third-party applications will no longer work. I have a etrex VistaC. If you're working within Windows, many external pieces of software can be used - I've used ExpertGPS and Topofusion with no problem. Garmin has released an interface guide to their USB driver, so the authors of these and other pieces of software (which I haven't used myself) have been able to make them compatible with the newer Garmins. The DeLorme software won't talk to the USB GPSr's directly (I'm working with Topo USA 4.0), but if you're willing to use another piece of software or two to do file conversion along the way, you can get routes and tracks backwards and forwards between the two. Live tracking is another matter - one perhaps better addressed by the above mentioned GPSgate. IMO, this is pretty much just DeLorme refusing to work with the Garmin USB driver. (They may have good reasons or not for doing so, but that's another matter). On the Mac, you will run into problems, given the lack of drivers (not to mention map-loading software). I've been using the Dec. 2004 beta of gpsbabel on OSX 10.3.8 from the command line with no problems to communicate with the VistaC over usb. Macs and GPS's are a whole other thread, though. NMEA is a serial protocol. A manufacturer might be able to support NMEA-formatted data strings over USB, but there is no way that you can take a piece of software that expect to talk over a serial port and have it talk over USB without either updating the software or inserting something in between. Since there are no standards for GPSr USB interfaces, the manufacturers have to create their own, thus guaranteeing that third party software will either need to incorporate code specific to the device, or be incompatible. Once you've guaranteed device specific code, there's no reason not to have the protocol over the USB be proprietary as long as you supply drivers and driver interface specifications. Keith Quote Link to comment
robertlipe Posted March 24, 2005 Share Posted March 24, 2005 In conversations with Thales on this before they're released, I've been unable to get this answered. (OTOH, since GPSBabel doesn't do realtime NMEA tracking and I don't carry a laptop while caching, I don't really care. :-) 60C and 76C have both USB and EIA232 serial. VistaC, Quest, Street*, C3xx, VistaC, and LegendC are USB only. None of them stream NMEA over USB; they use Garmin's proprietary positioning protocol as I said before. RK, it would need more than a physical electrical translation. A device like you're describing would actually need to be a USB host and it would have to know the details of the protocol. It's not a job for a $15 serial/usb adapater. reidster, you don't have to reverse engineer it; Garmin does produce a document describing it. (Of course, if its as accurate as most garmin protocol doc, prepare to attach it to a protocol analyzer and watch what Mapsource does anyway using the "spec" as a hint, but not the final word...) There is a way to do NMEA over USB that basically involves blasting NMEA sentences right on a bulk or isoch pipe where they can be trivially read by programs. Then programs will still need to be modified to deal with the new physical layer, but not a new protocol layer as Garmin chose to require. I've suggested this to Thales, but I don't know how it'll turn out. Between the two companies, I know which one I'm trusting to provide an "obvious" protocol implementation with documentation that'll actually match it. But depending on your NMEA needs (i.e. if you need REAL nmea conformance to connect to your autopilot or you're using some program that hasn't been updated to speak whatever USB variants are in question) it could still tilt the scales toward a unit with plain old serial. I would hope that a Mapsend-like substance with USB tracking will appear about the same times the units themselves do, but I don't have any scoop on that, either. Quote Link to comment
+D0T-C0M Posted March 25, 2005 Author Share Posted March 25, 2005 (edited) Thanks for all the replies. I had read somewhere that only garmin had proprietary protocol to work over a usb connection. I was wondering if the explorist had a similar option as well. I will no doubt keep my sportrak if it can't for those times I go on vacation and use my laptop to track in realtime. Edited March 25, 2005 by D0T-C0M Quote Link to comment
robertlipe Posted March 25, 2005 Share Posted March 25, 2005 If you're expecting to use whatever software you have on your laptop today, that's a wise move. Much of the software is likely to learn about the new units after they get in the hands of the developers and the installed base justifies the development time. It's not a speedy process. Quote Link to comment
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