ROBOT.LK

Hey guys,
I have been working on DTMF decoder project recently. It's simple project. I used PORTA of 16f876 to read the values from (parallel data) the decoder IC and set some other pins of PORTC high or low. At the end it worked fine. But after sometime I noticed that pic is not responding to digit 2. I have checked the voltages. At the decoder end of the connecting wire voltage was 3.45v and it was ok. But same wire at the PIC end voltage was 0.67v. How ever I have changed the digit and completed the project. But still wondering how it happened. How there can be two voltages at the two ends of the same wire ?

P.s. I checked the wire also. And it's ok.

Having two voltages (very different) at the ends of a wire is impossible. It could be dry soldering or a high resistance somewhere. Also double check that you have setup this pin on PORT A correctly. On PICs, PORT A is mostly multiplexed with several functionalities. So better be aware on that.