[SOLVED] Sim300 command inputting problem.

[tariq7868]

Hello , i have sim300 gsm module,, i have connected its serial port to pc via simple 3-5V converter & max232 ,, the problem is that when i power on the module (with baud rate set to 115200) i get "Call ready" on HyperTerminal. The problem is when i input 'AT' i dont get 'OK' response ,,,& i have also checked on other terminal softwares such as MikroC's terminal & Advanced Serial Port Terminal,, but not getting any response...plz help me,,, Have already checked the level convertors ,whcih are alright...

Added after 25 minutes:

i have used only tx & rx pins ,, & have grounded the rts pin

 

[LAKSHMIPATHY]

Have you checked the compatibility of the GSM modem.If it is TTL compatible then MAX232 is not needed

 

[tariq7868]

Actually i was using USB 2 Serial convertor (as i had no serial in my PC) for serial comm. between my pc & GSM Modem, so it was found to be problem with this convertor, it was only transmitting data from modem to PC alright but not from PC to modem. so problem was solved by changing the USB2Serial convertor..