Interfacing a Cell Phone modem to a computer

                                               INTERFACING SIM300 VIA COMPUTER

This is an interesting topic. In this tutorial we will find out how to connect a cell phone module to a computer.

First you will need a SIM300 module. You can get it from a leading electronics store for around 800 to 1000 rupees. You will need HyperTerminal; I am saying this because if you have windows 7 or higher version, HyperTerminal will not readily available. All you need to do is get the whole HyperTerminal folder from a Windows XP PC. Or you can search for HyperTerminal on the internet. Just get the HyperTerminal application file and the .dll file. That is enough you don’t need anything now.

Now configure the HyperTerminal. As soon as you open the HyperTerminal it will ask you to set up a new connection. Give a connection name, set the baud rate as 9600 (the baud rate for the SIM300 will be given in the manual, it is mostly 9600). One start bit, one stop bit, flow control through hardware. Leave all the settings as it is. You are ready to connect the SIM300 module.

Now just get a RS232 9pin serial connector to connect the SIM300 module to the computer. If you are using a laptop you won’t be having a serial connection so you will have to use a USB to RS232 serial connector named DB9 by BAFO. Now just connect both the module and the computer.

COMMANDS TO BE GIVEN VIA HYPERTERMINAL

To make a call

1.       AT (press Enter). You will get the response as OK.

2.       ATD<phone number>;

This will call the desired phone number.

3.        ATH(To hang up the call)

To Pick up a call

1.       When you want to pick up a an incoming call give ATA (press enter)

To send an SMS

1.       AT(Press Enter)

2.       AT+CMFG=1(Press Enter)

3.       AT+CMGS=”<phone number>”

4.       >Type the message(Press ctrl+z)