BG77 LTEM - HTTP DNS error (CME ERROR 714) after few hours

Hello,

We are facing issues related to HTTP DNS ERROR (+CME ERROR 714) with using BG77 module. It appears only few hours after boot.

Most of the time we are asking GNSS NMEA frames, but every minute we power off the GPS, do a HTTPS POST REQUEST to send GNSS data, then we power-on the GPS again and go further with NMEA messages.

This works fine, however few hours after boot every QHTTPPOST command gets a “+CME ERROR 714” (corresponding to a HTTP DNS error). Nothing is received by our server, and we never get back to the normal behaviour with HTTP 200 return code. It’s only resolved by a battery power-off/power-on of our device.

AT commands Init sequence:
RDY
APP RDY
ATE1
OK
AT+QCCID
+QCCID: 89320420000002505905
OK
AT+QGPSXTRA?
+QGPSXTRA: 1
OK
AT+QCFG=“iotopmode”,0
OK
AT+QCFG=“nwscanseq”,02
OK
AT+CREG=1
OK
AT+QICSGP=1,1,“bicsapn”,"","",0
OK
AT+QHTTPCFG=“sslctxid”,1
OK
AT+QSSLCFG=“sslversion”,1,3
OK
AT+QSSLCFG=“ciphersuite”,1,0xFFFF
OK
AT+QSSLCFG=“seclevel”,1,0
OK
AT+QHTTPCFG=“requestheader”,1
OK
AT+QHTTPURL=21,20
CONNECT
OK
AT+QGPSCFG=“priority”,1
OK
AT+COPS?
+COPS: 1
OK
AT+COPS=4,0,“Orange F”,8
OK
AT+CEDRXS=2,5,“0100”
OK
AT+QGPSCFG=“nmeasrc”,1
OK
AT+QGPS=1
OK
AT+QGPSCFG=“priority”,0
OK

GNSS usual behaviour every 3 seconds:
AT+QGPSGNMEA=“GGA”
+QGPSGNMEA: $GPGGA,182259.00,— XXX ----1,06,0.9,57.1,M,47.6,M,56
OK
AT+QGPSGNMEA=“RMC”
+QGPSGNMEA: $GPRMC,182259.00,— XXX —,E,0.0,220721,2.0,W,A,V
76
OK

Every minute for LTEM HTTPS POST request:
AT+QGPSEND
OK
AT+CREG?
+CREG: 1,5
OK
AT+QCSQ
+QCSQ: “eMTC”,-71,-97,110,-13
OK
AT+QIACT=1
OK
AT+QIACT?
+QIACT: 1,1,1,“100.65.75.46”
OK
AT+QIDNSCFG=1,“8.8.8.8”,“8.8.4.4”
OK
AT+QHTTPPOST=379,20,20
CONNECT
OK
+QHTTPPOST: 0,200,39
AT+QHTTPREAD=80
CONNECT
{“status”:“ok”,“tms”:1626978302.47648}
OK
+QHTTPREAD: 0
AT+QIDEACT=1
OK
AT+QGPSCFG=“nmeasrc”,1
OK
AT+QGPS=1
OK

When the issue appears during sending request sequence:
AT+QGPSEND
OK
AT+CREG?
+CREG: 1,5
OK
AT+QCSQ
+QCSQ: “eMTC”,-72,-96,127,-14
OK
AT+QIACT=1
OK
AT+QIACT?
+QIACT: 1,1,1,“100.65.75.46”
OK
AT+QIDNSCFG=1,“8.8.8.8”,“8.8.4.4”
OK
AT+QHTTPPOST=379,20,20
+CME ERROR: 714
AT+QIDEACT=1
OK
AT+QGPSCFG=“nmeasrc”,1
OK
AT+QGPS=1
OK

BG77 firmware version : BG77LAR02A04_01.002.01.002

Thanks for your help

based on your AT , you have use one roaming sim card , with roaming sim card , the BG95 will search network every 2 mins , i guess the root cause come from the procedure of network search ,

image

for the detail analysis , we need qXDM log to do more action .

pls try one local sim card first , If the problem persists,pls rech to support@quectel.com

Fixed with updating BG77 firmware to BG77LAR02A04_01.002.01.005 release