Dear Techies ,
i am newbies to GPRS,so can any one tell me which are the AT commands need to send reptedly in while loop and which commands need only one time? in the case of TCP server client connection and data transfer,my gsm module stop sending data while iam moving in car,it looks like socket is not closed or taking longer time?Iam using idea sim in that 2G connectivity?
Thanking you in advance
The commands remain the same, you just need to add intelligence in your software to reconnect when there is no response or loss of network. Implement timeouts for data waiting and eliminate infinite loops.
ok Thank you, for you response i added timeouts ,currently software working fine.need further testing.Another qustion is regarding embedded sim what are the changes required if we are using embedded sim,how we will store profile of operator and how we can change operator on the go?
Embedded SIM is just a SIM card with solderable pins. Nothing changes really.
ok my last question in this gprs,how to impliment secure communication, TLS,SSL in embedded side,iam using STM32 CONTROLLERS
There are commands for enabling SSL, Check my video on HTTPS communication on SIM900.
sorry Ravi,I couldnt find video on Https i could find only Http in the play list if you dont mind please send me link.
I guess i never posted it
You can use command AT+HTTPSSL=1 before executing a HTTPS request
You can use command AT+CIPSSL=1 before executing a SSL/TLS over TCP request
I think the encryption method or cipher is selected automatically.
Other commands remain same as for normal HTTP or TCP requests.
if you are doing encryption on MCU then you can look at STM32 GCP cube example code, it uses MBEDTLS
Ok,Thank you Ravi .yes iam trying to add MBEDTLS,as iam newbie to this TLS side very difficult to understand the topic,But now onward for any embedded product TLS will be mus so trying hard to learn.If you could plan a video on MBEDTLS integration to your project it will be great.Thank you