LilyGo T-Call SIM800L board location issues

kakka0903

Hello Everyone,

I really need some help troubleshooting location issues for the SIM800L. I am using the LiliyGO T-Call Sim800L and the R14.18 firmware. This is the response from the ATI command: SIM800 R14.18. My sim provider is Lebara (Netherlands) multimedia.lebara.nl is their APN.

It seems most other functions than location are working fine. I can communicate with the modem by sending AT commands. I connect to the GPRS network and can send HTTP requests and SMS messages.

At first i tried using the GSM location feature trough the Arduino TinyGSM library. That never worked, so i tried doing it myself with AT commands. The following code blocks shows my steps.

/* make bearer profile correct, activate it */
// make sure bearer profile one is correct
AT+SAPBR=3,1,Contype,GPRS
OK

// specify APN name
AT+SAPBR=3,1,APN,multimedia.lebara.nl        
OK         

// activate bearer profile 
AT+SAPBR=1,1     
OK

In many examples on the internet and in the datasheets from simcom's webpage they use double quotes for the string parameters like this:

AT+SAPBR=3,1,"Contype","GPRS"

This gives me an ERROR response instead of OK. So as you saw i do them without the double quotes which evidently seems to work fine.

After completing these commands, the indicator light on the LilyGO
board starts blinking faster (~3 per sec) indicating a gprs connection. After that i try getting the location.

/* Now for fetching the actual location  */
// set lbs server
AT+CLBSCFG=1,3,lbs-simcom.com:3002
OK

// try getting location + time
AT+CLBS=4,1                          
+CLBS: 1

OK

// try getting only location 
AT+CLBS=1,1                        
+CLBS: 1

OK

Both these commands gives me a locationcode 1 error, which indicates no location. Specified in the GSM location datasheet. Earlier i would commonly get locationcode 3 which would indicate NET error, but i think that maybe was due to incorrect bearer profile settings.

One problem might be that the LBS server from simcom is not working correctly, so i also tried another server address www.c4a.com.cn:3002. This one is from china.

/*Trying chinese LBS server */
// change lbs server setting
AT+CLBSCFG=1,3,www.c4a.com.cn:3002
OK

// trying to get location again
AT+CLBS=1,1 
+CLBS: 1

OK

// and the other one
AT+CLBS=4,1 
+CLBS: 1

OK

There is also this redundant location command, using AT+CIPGSMLOC, which does not work anymore. As expected not for me either.

/* trying redundant command */
AT+CIPGSMLOC=1,1
+CIPGSMLOC: 0,0.000000,0.000000,2021/10/23,16:38:47

OK

One last thing is that it might take some time for the network to calibrate before being able get location properly. I have tried this many times. Letting it sit connected for up to 2 hours, and trying every five minutes.

Some people have problems with power delivery to the board, but i do not think this is the case for me since i never have expected dropouts or restarts when using the board. My signal quality is also very good.

/* testing signal quality */
AT+CSQ
+CSQ: 31,0

OK

I have already reached out multiple places for help this github issue seems really similar to mine, but he is actually able to get a location. I left a comment at the bottom. I also posted in TinyGSM's gitter chat, and in the Arduino stack exchange

So yeah that is my problem. I feel like i have exhausted every option, I even tried a sim from another country. If anyone are able to help, that would be greatly appreciated.

Sukaibin

reference