Hi ,
I’m using TCP client sample code provided in the open AT for Q2686 module,
Its ran well on the evaluation board then I put the module and sim to my own designed board ,
After putting there its not registering to the network, its keep on polling at the poll_creg_callback function . I checked the sim connection, Gnd antenna connection, all are correct and as per the reference board.
I’m using airtel service provider.
When a GSM device (any GSM device - not just SiWi) transmits, it draws a huge peak of current - so, obviously, this is where any deficiencies in your power supply arrangements are going to show up!
This is why your board could start, and communicate with the board - neither of which takes much current - but then failed to register.