AT+CGPSINFOCFG=10,31 in the documentation responds with four GPGSV lines, one GPGGA and one GPVTG, but 31 would be the first five bits flipped on, so why only three different NMEA sentences?
66082 gave me PQXFI and another sentence which were one bit less than what I was aiming for. I'm going to try and shift the bits over by one to see what change I get.
1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144
132164 is the new number to try.
I'm also confused with the AT+CGPSNMEA and AT+CGPSINFOCFG commands which aside from the time component in the latter, appear to do the same thing according to the documentation. Unfortunately the documentation says an AT+CGPSDEL command should be sent during every shutdown. This means every time I have to reboot the module it has to do a GPS cold start which takes more than ten minutes. I adjusted my code to allow for a hot shutdown of the script when I just need to alter some of the code. The AT+CGPSNMEA documentation says a reboot needs to happen for any changes there so some of this time can't be recovered. I'm using this as a bit of a notepad to jot down my thoughts as I try and figure this out.
Okay, I'm getting somewhere.
I set AT+CGPSNMEA and AT+CGPSINFOCFG to 132164. For whatever reason I'm no longer getting a positional fix using AT+CGPSINFO, but the buffer is filling with at least some of what I'm looking for.
Likewise, GLGSV lists the number of GLONASS satellites in view and it looks like it has the same format. This data shows there were 16 GPS satellites in range and 9 GLONASS satellites in range. So I've received the data corresponding to bits 2 and 6, but am still missing 10 and 17. I suppose I could just call this good enough, but I want to learn how this works. Why am I no longer able to get a coordinate fix with CGPSINFO? Why can't I get the NMEA sentences for the other bits?
There's another change that I've noticed and I don't know if it correlates with anything. There's an LED below the PWR LED and it's labeled NET. It used to be off until the code turned the SIM7600 module on. Likewise it would turn off when the program sent the shutdown sequence. Now it's just on all of the time. Even if I shut everything down and inplug the pi, the second I plug it back in both LED's turn on. I'm wondering if there's a way to reset the HAT to the factory default.
66082 gave me PQXFI and another sentence which were one bit less than what I was aiming for. I'm going to try and shift the bits over by one to see what change I get.
1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144
132164 is the new number to try.
I'm also confused with the AT+CGPSNMEA and AT+CGPSINFOCFG commands which aside from the time component in the latter, appear to do the same thing according to the documentation. Unfortunately the documentation says an AT+CGPSDEL command should be sent during every shutdown. This means every time I have to reboot the module it has to do a GPS cold start which takes more than ten minutes. I adjusted my code to allow for a hot shutdown of the script when I just need to alter some of the code. The AT+CGPSNMEA documentation says a reboot needs to happen for any changes there so some of this time can't be recovered. I'm using this as a bit of a notepad to jot down my thoughts as I try and figure this out.
Okay, I'm getting somewhere.
I set AT+CGPSNMEA and AT+CGPSINFOCFG to 132164. For whatever reason I'm no longer getting a positional fix using AT+CGPSINFO, but the buffer is filling with at least some of what I'm looking for.
GPGSV lists the GPS satellites in view. I found some NMEA documentation here which helps me to decode it. The first number is the total number of sentences being sent with the second number corresponding to the index number of that particular sentence. The third number is some of what I've been looking for - the number of GPS satellites in view.$GPGSV,4,1,16,...
$GPGSV,4,2,16,...
$GPGSV,4,3,16...
$GPGSV,4,4,16,...
$GLGSV,3,1,09,...
$GLGSV,3,2,09,...
$GLGSV,3,3,09,...
Likewise, GLGSV lists the number of GLONASS satellites in view and it looks like it has the same format. This data shows there were 16 GPS satellites in range and 9 GLONASS satellites in range. So I've received the data corresponding to bits 2 and 6, but am still missing 10 and 17. I suppose I could just call this good enough, but I want to learn how this works. Why am I no longer able to get a coordinate fix with CGPSINFO? Why can't I get the NMEA sentences for the other bits?
There's another change that I've noticed and I don't know if it correlates with anything. There's an LED below the PWR LED and it's labeled NET. It used to be off until the code turned the SIM7600 module on. Likewise it would turn off when the program sent the shutdown sequence. Now it's just on all of the time. Even if I shut everything down and inplug the pi, the second I plug it back in both LED's turn on. I'm wondering if there's a way to reset the HAT to the factory default.
Statistics: Posted by MadDokK — Sat Feb 24, 2024 6:22 pm