SIM700 AT Command Problem and USB Driver

[angle9]

Hi

I am developing GPRS application with SIM700 module.
I got problem some of module is miss-setting, so i don't know what is its serial setting (baud rate, data, stop bit, parity)? So every time I send AT command the module always reply 0xFF.
Anybody can help me? Can we return to original setting?

And is there any link to download SIM700 USB driver?

Thanks

 

[ckshivaram]

let us know,, which operating system you are using. do you know hyperterminal.. in hyperterminal select the port to which the modem is connected, once you click ok then it has option of port settings...
there set baud rate 9600, data bits 8, number of stop bits 1, flow control none , parity none.

the power ON the modem after connecting it to system....

then type AT you should see OK on the terminal.....

anytime you want to go to default settings type command AT&F (enter key)

 

[angle9]

Hi ckshivaram
Thanks for the reply...

Sorry I will make clear the problem. All the setting actually is OK.
We develop GSM application using this SIM700. During production, we found some SIM700 module CAN NOT POWER ON in our product. But if we check using SIM700 development board, it is OK, no problem.
We already follow the requirement to turn on the module as mentioned in datasheet, IGT timing set >500 ms. Hardware design also already follow SIM700 datasheet.

Please help me..thanks

 

[ckshivaram]

One simple thing could do is to see, if can do is....... replace the modules and see if it is module problem or board problem. Next see the power connections between board and modem.