MEGA + GPRS v1.2 : Detecting new SMS recieved


I use Seeduino MEGA & shield GSM/GPRS v1.2. They work fine !

I want my Mega to get new SMS notification without using AT command (+CMGR…) , because response time is to big.

I noticed that :

  • The GSM/GPRS shield has many output pins : DTR, DCD, DSR …
  • The AT command CNMI enable to select the procedure for how the receiving of new messages from the network is indicated to the TE…

So , is it possible to connect one of the ouptup pins of my shield to one input pin of my Mega in order to detect new SMS notification ?
If yes, what is the output pin to use on the shield ? What are the parameters for the AT CNMI command ?

(I read the AT commande reference guide but I did not understand how to do the job …)

Many thanks !