i have G BOARD http://www.simplelabs.co.in/content/gboard-gsm-based-arduino-platform
it has d0 d1 d2 d3 jumper for hardware and software rx tx with arduino
i also GSM_shield library
but i cant receive response of SIM900 Lib_IM120411004_GBoard_SIM900.zip
i try to send AT using serial monitor of aduino..
AT but it cant response
so i need to change in my library or not...