No GPS data or errors from EC25-A

Raspberry Pi Network HATs 3G/4G&LTE Base HAT
1

EC25-A module with LTE Main & Diversity & GNSS Triple Port u.FL Antenna (SixFab S78 part number).

Indoor or outdoor I get the same NMEA sentences with no valid data:

$GPVTG,,T,,M,,N,,K,N*2C                                                         
$GPGSA,A,1,,,,,,,,,,,,,,,*1E                                                    
$GPGGA,,,,,,0,,,,,,,,*66                                                        
$GPRMC,,V,,,,,,,,,,N*53                                                         
$GPVTG,,T,,M,,N,,K,N*2C                                                         
$GPGSA,A,1,,,,,,,,,,,,,,,*1E                                                    
$GPGGA,,,,,,0,,,,,,,,*66                                                        
$GPRMC,,V,,,,,,,,,,N*53

Any idea as to what to check? Could the EC25 module be bad (cellular modem works – I did buy it used on ebay)?

Thanks

2

Hi @williamkeeling,

About your issue, please confirm the following information:

  • Good sky view or anything in the way? Do you keep the Pi clock close to the correct time?
  • Please confirm you have connect the GPS antenna, and place it in the outside environment.
  • The following GNSS manual for your reference. Please check the values returned using AT command by following the reference. Thank you.
3

Both inside and outside (nothing between sat and antenna) no GPS data. Clock kept in sync by ntpd. Yes GPS antenna in place and outside case and outdoors – still no GPS data.

4

Which HAT and interface(ttyUSB?) do you use?
You can also check out the tutorial here.

5

Raspberry Pi 3G/4G & LTE Base HAT. /dev/ttyUSB2 to turn on GPS (AT+QGPS=1) and /dev/ttyUSB1 to receive the data. I get replies on USB1 but no GPS data (see above).

6

Here we are not able to find the source of the error, You may check the Firmware of the module and for better support, you may contact the module OEM support forum.

7

tried a new EC25-A module and now I get $GPGSV messages but still no position fixes

$GPGSV,4,1,13,03,57,272,29,04,38,320,26,22,54,226,16,26,61,064,17*7E            
$GPGSV,4,2,13,31,26,049,28,01,04,226,,02,,,,06,,,*7B                            
$GPGSV,4,3,13,07,,,,08,,,,10,33,168,,12,03,203,*7C                              
$GPGSV,4,4,13,13,45,330,*48                                                     
$GPVTG,,T,,M,,N,,K,N*2C                                                         
$GPGSA,A,1,,,,,,,,,,,,,,,*1E                                                    
$GPGGA,,,,,,0,,,,,,,,*66                                                        
$GPRMC,,V,,,,,,,,,,N*53                                                         
$GPGSV,4,1,13,03,57,272,29,04,38,320,26,22,54,226,16,26,61,064,17*7E            
$GPGSV,4,2,13,31,26,049,28,01,04,226,,02,,,,06,,,*7B                            
$GPGSV,4,3,13,07,,,,08,,,,10,33,168,,12,03,203,*7C                              
$GPGSV,4,4,13,13,45,330,*48                                                     
$GPVTG,,T,,M,,N,,K,N*2C                                                         
$GPGSA,A,1,,,,,,,,,,,,,,,*1E                                                    
$GPGGA,,,,,,0,,,,,,,,*66                                                        
$GPRMC,,V,,,,,,,,,,N*53
8

never mind just after that post position fixes started coming thru :slight_smile:

got a few of these on /dev/ttyUSB2 – any idea what it means

+QGPSURC: "xtradataexpire",0,"1980/01/05,19:00:00"

9

Looks like user error both EC25-A modules work given enough time (takes about 1 minute to start see satellites and another minute or 2 to get position fixes).

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