Shall we start again?

[spuffock]

If a program that uses porta 6,7 output only, runs on a PIC16F886, can anyone think of a reason why it might not run on a PIC16F887?

 

[picasm]

Ok, It may be completely irrelevant, but I noticed a microchip design using an 887 had 0.1uF decoupling caps across both sets of power pins on the chip.

Perhaps that is what is needed if you have not already done so.

 

[ssylee]

Did you also check the fusebit settings on a PIC16F887 of that particular program?

 

[spuffock]

PICASM- That's just the bloody stupid thing that I'll have forgotten. I wouldn't be at all surprised-- I'll go do it now!

SSYLEE- The program in question was written to test a new board with an 887. It checked out with all the other ports used as digital outputs, but failed with a6 floating and a7 low.When it failed, the fusebits were checked first. A new board was fitted with just the processor , in order to eliminate any loading effects, and tried again. It was at this point that it was noticed that the processor supply current was pulsing to 90 milliamps, with nowhere external to go.
I supposed that the chip might be faulty, and tried 2 more (from the same batch) with the same results. I then programmed an 886, with the same program, and it worked.
SO WHAT NOW

Just tried the decoupling- no help. It was a good idea,though.

 

[Nigel Goodwin]

What's the big idea! - deleting all your posts in the previous thread!.

Lot's of people have offered you help and advice, and you've basically 'kicked them in the teeth' by deleting all your posts, making duplicate threads is also NOT allowed!.

This is not acceptable behaviour!, and any further repetition will result in your being banned!.

Moderator.