Hi Shahzad,

In fact normally the answers are hidden within the data sheet.

The chip OEMs normally provide everything in the data sheet (as they think) required necessarily by an application designer.

From your previous postings, it looks like you only want to replace your "fingers" with the out puts from micro so to dial a number from a keypad inputs.......

That's not a wise approach, it is under-utilization of both the micro power and yours too.

(I once wanted to give an ascii stream to a software from key board like that. I tried to control the keys from the micro, and then I had to curse myself when I learned the Scan Codes and then replaced the keyboard with the micro attached to the PC. So instead of replacing my fingers on keyboard I replaced the keyboard with the micro.)

So the bottom line is that if you try real hard to contemplate the data sheet you will find a way even without an application note. Though I myself find it too hard to move a step without a downloaded AN.

But when it came to building an autodialer with MT8880CE I had to understand the data sheet, as little or no help was available. Data sheet was good enough to make it.

Anyway, the wise idea would be as already outlined by Ijaz Ahmad above.

If you choose 8880, I can be of directional help for you.

Babar