I have a strange behavior that happens sometimes (it’s random). The normal behavior is to receive the PPS signal and 180-200ms later to receive the NMEA data stream, that works fine, but sometimes this scheme is not respected and I receive the PPS signal, after 1 second I receive another PPS signal and 180ms later I receive the 2 frames of serial data. This is a problem when trying to use GPS as a time source. Is it an already known issue and is it fixable?
GPS model L80-M39 (L80GR01A10S) @ 57600 bauds (8N1), with PPS signal trough RING pin.
Normal behavior
03/13 11:22:56.994 PPS
03/13 11:22:57.182 $GPZDA,142257.000,13,03,2023,53
03/13 11:22:57.194 $GPGSA,A,3,21,31,27,28,10,08,32,04,01,03,1.13,0.78,0.8204
03/13 11:22:57.202 $GPGLL,2049.5323,S,06014.5963,W,142257.000,A,A50
03/13 11:22:57.208 $GPTXT,01,01,02,ANTSTATUS=OK3B
03/13 11:22:57.994 PPS
03/13 11:22:58.172 $GPZDA,142258.000,13,03,2023,5C
03/13 11:22:58.183 $GPGSA,A,3,21,31,27,28,10,08,32,04,01,03,1.13,0.78,0.8204
03/13 11:22:58.192 $GPGLL,2049.5323,S,06014.5963,W,142258.000,A,A5F
03/13 11:22:58.198 $GPTXT,01,01,02,ANTSTATUS=OK3B
Structure error
03/13 11:23:05.993 PPS
03/13 11:23:06.993 PPS
03/13 11:23:07.172 $GPZDA,142306.000,13,03,2023,56
03/13 11:23:07.183 $GPGSA,A,3,21,31,27,28,10,08,32,04,01,03,1.13,0.78,0.8204
03/13 11:23:07.192 $GPGLL,2049.5323,S,06014.5963,W,142306.000,A,A55
03/13 11:23:07.197 $GPTXT,01,01,02,ANTSTATUS=OK3B
03/13 11:23:07.203 $GPZDA,142307.000,13,03,2023,57
03/13 11:23:07.214 $GPGSA,A,3,21,31,27,28,10,08,32,04,01,03,1.13,0.78,0.8204
03/13 11:23:07.223 $GPGLL,2049.5323,S,06014.5963,W,142307.000,A,A54
03/13 11:23:07.229 $GPTXT,01,01,02,ANTSTATUS=OK3B
03/13 11:23:07.993 PPS
03/13 11:23:08.993 PPS
03/13 11:23:09.172 $GPZDA,142308.000,13,03,2023,58
03/13 11:23:09.183 $GPGSA,A,3,21,31,27,28,10,08,32,04,01,03,1.13,0.78,0.8204
03/13 11:23:09.192 $GPGLL,2049.5323,S,06014.5963,W,142308.000,A,A5B
03/13 11:23:09.197 $GPTXT,01,01,02,ANTSTATUS=OK3B
03/13 11:23:09.203 $GPZDA,142309.000,13,03,2023,59
03/13 11:23:09.214 $GPGSA,A,3,21,31,27,28,10,08,32,04,01,03,1.13,0.78,0.8204
03/13 11:23:09.223 $GPGLL,2049.5323,S,06014.5963,W,142309.000,A,A5A
03/13 11:23:09.229 $GPTXT,01,01,02,ANTSTATUS=OK3B
Thanks in advance !