LoNet - GSM/GPRS/GPS Breakout sim808


Sorry for my bad english.

I want to use a-gps with this module. But don’t know how. I try to search commands for that but only found settings for other simcom products. I try them also but get errors.

Products wiki page told that it also supports A-GPS, but can someone says how ?

Second when i use AT+CGPSINF=0 in serialmonitor or in my code i don’t get all the answers. Does it means that i have to increase size of buffer from HardwareSerial.cpp. I use Arduino uno rev3. with this board.

If you have the beginning of the the answer to the AT command you just sent and then it stops : Yes probably that the buffer size is too small. I use a char gprsBuffer[256] to get that info. Probably too much, but it works.

If you don’t have any answer at all…than the problem is not the buffer.

have you managed to get a good gps position with the device ? I get a location, but it’s like a 100km away from where I am ! I don’t know if it’s a bug in the device or just that my GPS signal is too small.


Yes i have get exact position with this device.

i need to test bigger buffer.

Anyone has answer to that A-GPS question ?


can i get help to exact position with this device. i can get the latitude & longitude but it far away my location. by the way can u explain what is buffer size. i have read in forum, in comment tell about buffer size. so i also want what buffer size need to used, cause i use Intel Galileo gen 2 board. please can help me. Sorry for my bad English.

I’ve managed to get the location right with the “AT+CGPSINF=2” at command

The coordinates that the device gives you are good, but they are not the right format.

You have to first pass the location that it gives you through this site :

it will slightly change the data.

Then you pass the “new” data from the first site to this site :
fcc.gov/encyclopedia/degrees … al-degrees

After that you’re good to go on google map and type you’re location to see if it fits ! It seems very precise !

Now it would be very nice to have the tools to write embedded program for the sim808 chip !
GPS fonctionne !.jpg