[SOLVED] The +++ command problem

[ponnus]

Hi,
am using sim 300 at commands to connect to gprs via gsm modem. I've entered data mode by ATO command. But after sending data, I cannot switch to command mode using +++ command. I've given 2 sec delay before and after the command. Also, I haven't added 'carriage return" at the end. I just typed it as a string. ie,
send2gsm("+++");
(tat's my own function to send through gsm).
Can anyone help me? plz.....

 

[horace1]

many modems require a carriage return character \r as well as \n, try

send2gsm("+++\r\n");

however, reading the SIM300 manual

it states
To prevent the +++ escape sequence from being misinterpreted as data, it should comply to following sequence:
1. No characters entered for T1 time (0.5 seconds)
2. “+++” characters entered with no characters in between
3. No characters entered for T1 timer (0.5 seconds)
4. Switch to Command mode, otherwise go to step 1.

so if you wait a second, send +++ and wait 0.5 second it should go into command mode

 

[ponnus]

Ok.I've given more delay and it worked. thank u for ur response