Finding some examples

[Bart_]

Dear community,

This might sound a bit weird, but I'm 16 years of age and very interested in electronics. I've been programming for about 6 years (mainly Java) and now I want to try something different.

I was playing around a bit with Multisim and was trying to make the DTMF keypad make leds burn, but I could not manage to find out how to make difference in frequency.

I know, I am new and I should be following a complete course or graduation first but I think it's fun to do, so I hope someone could be able to point be into the right direction.

Kind regards, Bart

[Tien_P]

Hi Bart,

To understand how the keypad works have a look at this diagram:

http://www.8051projects.net/keypad-interfacing/introduction.php

This keypab component available is available in the Multisim and you can find it in the Advanced Peripherals group. 

To use the keypad, you have to use other components decode which button to a user pressed.  There is an example circuit installed with Multisim, select File>>Open Samples>>MCU>>8051>>Calculator.   In this case, we are using an 8051 MCU to determine which button the user pressed then output the results.

To generate different frequencies, there are custom component that you can buy such as UM91214 that will do what you want but this component is not available in the Multisim database.