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Ken McDonald
- 28th December 2004, 16:46
Hi everyone,

I am very new to PIC microcontrollers. My friend introduced them to me. My experience is with hardware design, not programming, but I'm trying to learn.


I am working with a PIC16F877. When power is applied, all of the outputs flash on and off during power up. Is there a way to power the 877 up with the outputs set to low? Setting them to inputs during power up will not work because the the outputs are connected to other gates.

Any help or information on this would be very helpful.

Thanks,

Ken McDonald

Ken McDonald
- 28th December 2004, 17:06
Oh brother.....

After taking a look at the circuit with a scope, I have discovered that its the gates connected to the outputs that come up high during power up. I don't know why I didn't scope first and then post the problem. I assumed that the 877 was causing the problem during power up. Sorry.

Ken McDonald