I am thankful to everyone for answering my questions.

Now, I need help in interfacing mobile with computer through serial port using visual basic. The signal obtained from RS232 will be passed to IC MAX232. I found some code in VB for serial port, but doesnt seem to work.

The cable used for connection has 9 pins from one side and 4 pins from the other end. I was told that, I have to make some connections internally, by joining some pins, which I will be doing. But, how should the 4 pins from the end be connected??? Can anyone plz send me the Complete information and the proper code in VB for serial port communication, please???

I have searched a lot on internet and tried with lot of codes, but they dont give proper output. First of all, I want to do a simple test of the cable, by obtaining the requied voltage for MAX232, plz tell me.

Thanx a lot.......

 

An easy way to test your hardware is to use hyperterminal to analyze the incoming/outgoing data, along with an LED and a resistor to verify the connections.

Connect an LED/resistor across the output side of your hardware, then by just pressing 'RETURN' in hyperterminal you should see the LED light up each time you press 'RETRUN'.

Good luck.

 

I presume when you say "mobile" you are referring to a GSM Phone??
Does this cable you have, connect directly to a PC? If it is specifically a UART cable then there is no need for the MAX232 chip at all!!!!