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Problem with L293D and PIC 16F877A

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superadamwo

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Hi,
I've got a "firefighting" robot project I've been working on that was working great for the past month or two. I'm using an L293D to drive two motors, which are controlled by outputs from the PIC chip. Yesterday the motors stopped working and I'm having trouble figuring out how to fix them. The problem I think I've identified is that the voltage relative to ground on Pin 1 of the L293D is 0.7 when it should be the ~6v I'm giving to the board. However, when I disconnect the two PIC inputs on that side of the chip, the voltage goes back up to 6v. The voltage output to the motor on that side is 1v on both pins. Like I said, all of this worked a few days ago, so I'm looking for reasons why it could have stopped working since then. I tried replacing the L293D chip but the same problem is still happening. I attached the schematic I'm using for the motors.
Sorry if I left anything out or sound like an idiot, this is a high school project so I'm not an expert or anything
Thanks for the help.

*title is wrong, it's a 16F877A (fixed by moderator)
 

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hi,
Its possible that you have blown the PIC output pins, do you have another programmed PIC you can try.?

Also ensure that the 0V line for the PIC and LM293D is a good connection.
 
I do, but I've measured the voltage on the output pins and they are giving a full 5v. I'll be sure to try that when I get a chance though.
As far as I can tell, the grounds on each board are properly connected to each other.
 
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