Question regarding GPS sentence formats

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Question regarding GPS sentence formats

Author	Message
tmn_pilot	t tmn_pilot posted 4/28/2022 7:21:13 PM Topic Details Share Topic
t Group: Forum Members Posts: 3, Visits: 1	Hi Skydemon. I have a question regarding the format of GPS NMEA sentences used in Skydemon. If I connect my 10 years old GPS receiver to Skydemon thru Wifi "Use PilotAware", it connects instantly. However if I try to use my new GPS receiver, it will not connect. I suspect that the issue is related to the "new" NMEA identifiers, like $GPRMC in the new receiver is named $GNRMC etc. Think it is because the receiver support GNSS. Here is a log of NMEA from the new receiver: 2022-04-28 20:54:47.562 32328-32363/com.example.nmealog D/NMEA: $GNRMC,185448.00,A,5623.354200,N,00953.665973,E,0.0,,280422,0.2,W,A,V60 2022-04-28 20:54:47.563 32328-32363/com.example.nmealog D/NMEA: $GNGNS,185448.00,5623.354200,N,00953.665973,E,AAANNN,21,0.6,12.9,43.6,,,V12 2022-04-28 20:54:47.564 32328-32363/com.example.nmealog D/NMEA: $GNGGA,185448.00,5623.354200,N,00953.665973,E,1,12,0.6,12.9,M,43.6,M,,4D 2022-04-28 20:54:48.523 32328-32363/com.example.nmealog D/NMEA: $GPGSV,3,1,11,01,85,223,21,03,48,239,14,08,14,177,33,14,11,267,22,162 2022-04-28 20:54:48.527 32328-32363/com.example.nmealog D/NMEA: $GPGSV,3,2,11,17,33,307,22,19,14,319,25,21,59,130,27,22,47,081,32,165 2022-04-28 20:54:48.542 32328-32363/com.example.nmealog D/NMEA: $GPGSV,3,3,11,31,04,105,19,32,35,056,25,04,03,188,,15B 2022-04-28 20:54:48.544 32328-32363/com.example.nmealog D/NMEA: $GLGSV,2,1,07,86,16,139,22,79,14,327,15,65,30,208,13,88,47,310,16,179 2022-04-28 20:54:48.550 32328-32363/com.example.nmealog D/NMEA: $GLGSV,2,2,07,87,80,158,13,71,40,045,33,72,77,153,16,140 2022-04-28 20:54:48.554 32328-32363/com.example.nmealog D/NMEA: $GAGSV,2,1,08,03,50,156,29,05,45,067,29,08,10,194,29,09,05,035,17,77B 2022-04-28 20:54:48.559 32328-32363/com.example.nmealog D/NMEA: $GAGSV,2,2,08,13,34,295,24,15,83,206,24,21,12,292,25,01,12,340,,770 2022-04-28 20:54:48.565 32328-32363/com.example.nmealog D/NMEA: $GNGSA,A,3,01,08,14,17,19,21,22,31,32,,,,0.8,0.6,0.6,13B 2022-04-28 20:54:48.568 32328-32363/com.example.nmealog D/NMEA: $GNGSA,A,3,71,79,86,87,88,,,,,,,,0.8,0.6,0.6,233 2022-04-28 20:54:48.569 32328-32363/com.example.nmealog D/NMEA: $GNGSA,A,3,03,05,08,09,13,15,21,,,,,,0.8,0.6,0.6,339 2022-04-28 20:54:48.570 32328-32363/com.example.nmealog D/NMEA: $GNVTG,,T,,M,0.0,N,0.0,K,A3D 2022-04-28 20:54:48.571 32328-32363/com.example.nmealog D/NMEA: $GNDTM,P90,,0000.000024,S,00000.000000,E,0.969,W845E 2022-04-28 20:54:48.572 32328-32363/com.example.nmealog D/NMEA: $GNRMC,185449.00,A,5623.354200,N,00953.665970,E,0.0,,280422,0.2,W,A,V62 All sentences have correct checksum. Is there a solution to this, or do I have to keep using "old" GPS receivers? Best regards Thomas
	Reply Like 1
TouchTheSky	T TouchTheSky posted 4/29/2022 5:20:51 AM Post Details Share Post
T Group: Forum Members Posts: 151, Visits: 4K	+x tmn_pilot - 4/28/2022 7:21:13 PM Hi Skydemon. I have a question regarding the format of GPS NMEA sentences used in Skydemon. If I connect my 10 years old GPS receiver to Skydemon thru Wifi "Use PilotAware", it connects instantly. However if I try to use my new GPS receiver, it will not connect. I suspect that the issue is related to the "new" NMEA identifiers, like $GPRMC in the new receiver is named $GNRMC etc. Think it is because the receiver support GNSS. Here is a log of NMEA from the new receiver: 2022-04-28 20:54:47.562 32328-32363/com.example.nmealog D/NMEA: $GNRMC,185448.00,A,5623.354200,N,00953.665973,E,0.0,,280422,0.2,W,A,V60 2022-04-28 20:54:47.563 32328-32363/com.example.nmealog D/NMEA: $GNGNS,185448.00,5623.354200,N,00953.665973,E,AAANNN,21,0.6,12.9,43.6,,,V12 2022-04-28 20:54:47.564 32328-32363/com.example.nmealog D/NMEA: $GNGGA,185448.00,5623.354200,N,00953.665973,E,1,12,0.6,12.9,M,43.6,M,,4D 2022-04-28 20:54:48.523 32328-32363/com.example.nmealog D/NMEA: $GPGSV,3,1,11,01,85,223,21,03,48,239,14,08,14,177,33,14,11,267,22,162 2022-04-28 20:54:48.527 32328-32363/com.example.nmealog D/NMEA: $GPGSV,3,2,11,17,33,307,22,19,14,319,25,21,59,130,27,22,47,081,32,165 2022-04-28 20:54:48.542 32328-32363/com.example.nmealog D/NMEA: $GPGSV,3,3,11,31,04,105,19,32,35,056,25,04,03,188,,15B 2022-04-28 20:54:48.544 32328-32363/com.example.nmealog D/NMEA: $GLGSV,2,1,07,86,16,139,22,79,14,327,15,65,30,208,13,88,47,310,16,179 2022-04-28 20:54:48.550 32328-32363/com.example.nmealog D/NMEA: $GLGSV,2,2,07,87,80,158,13,71,40,045,33,72,77,153,16,140 2022-04-28 20:54:48.554 32328-32363/com.example.nmealog D/NMEA: $GAGSV,2,1,08,03,50,156,29,05,45,067,29,08,10,194,29,09,05,035,17,77B 2022-04-28 20:54:48.559 32328-32363/com.example.nmealog D/NMEA: $GAGSV,2,2,08,13,34,295,24,15,83,206,24,21,12,292,25,01,12,340,,770 2022-04-28 20:54:48.565 32328-32363/com.example.nmealog D/NMEA: $GNGSA,A,3,01,08,14,17,19,21,22,31,32,,,,0.8,0.6,0.6,13B 2022-04-28 20:54:48.568 32328-32363/com.example.nmealog D/NMEA: $GNGSA,A,3,71,79,86,87,88,,,,,,,,0.8,0.6,0.6,233 2022-04-28 20:54:48.569 32328-32363/com.example.nmealog D/NMEA: $GNGSA,A,3,03,05,08,09,13,15,21,,,,,,0.8,0.6,0.6,339 2022-04-28 20:54:48.570 32328-32363/com.example.nmealog D/NMEA: $GNVTG,,T,,M,0.0,N,0.0,K,A3D 2022-04-28 20:54:48.571 32328-32363/com.example.nmealog D/NMEA: $GNDTM,P90,,0000.000024,S,00000.000000,E,0.969,W845E 2022-04-28 20:54:48.572 32328-32363/com.example.nmealog D/NMEA: $GNRMC,185449.00,A,5623.354200,N,00953.665970,E,0.0,,280422,0.2,W,A,V62 All sentences have correct checksum. Is there a solution to this, or do I have to keep using "old" GPS receivers? Best regards Thomas Just a quick thought: some GPS can be configured so that even in case of GNSS $GPRMC is sent. The configuration parameter is called "Talker ID" which needs to be set to "GPS".
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Tim Dawson	Tim Dawson posted 5/3/2022 10:17:35 AM Post Details Share Post
Group: Forum Members Posts: 7.8K, Visits: 8.4K	The GPS sentence decoding in SkyDemon is designed for older (traditional) GPS receivers. Modern phones, tablets etc do this decoding themselves and pass them to SkyDemon through Location Services.
	Reply Like 1
tmn_pilot	t tmn_pilot posted 5/5/2022 6:19:59 PM Post Details Share Post
t Group: Forum Members Posts: 3, Visits: 1	+x Tim Dawson - 5/3/2022 10:17:35 AM The GPS sentence decoding in SkyDemon is designed for older (traditional) GPS receivers. Modern phones, tablets etc do this decoding themselves and pass them to SkyDemon through Location Services. Hi Tim Thx for clarifying. I'll look for a compatible GPS receiver for now. Any chance you'll update the GPS decoding in the future? Best regards Thomas
	Reply Like 1
Tim Dawson	Tim Dawson posted 5/6/2022 9:43:51 AM Post Details Share Post
Group: Forum Members Posts: 7.8K, Visits: 8.4K	I can't foresee a situation where we'd get much demand for it, but if we do, then we would do the work.
	Reply Like 2