MCLR pin

Cantafford said:

So basically driving this pin to 0 will erase the program from my pic.

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Ian Rogers said:

Not quite..... Driving MCLR low just resets the PC to 0... ( Program counter ) If MCLR is enabled you need to keep it high to run a program and breifly short it to ground to reset the pic...

If it is disabled, then the pin is used as a input ( sometimes an output as well )..

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Cantafford said:

And if it's disabled how can I erase the program from the pic?
Or I can just download a hex file on it and it will overwrite the previous one?

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jpanhalt said:

Is this what you mean regarding using MCLR as an output: https://www.electro-tech-online.com/threads/using-mclr-as-an-output.35349/

Or is it a more legitimate output on some newer PIC's?

John

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Nigel Goodwin said:

Same as you always do, by entering programming mode and erasing the PIC - although it's rare to do this without programming it as well, as the first part of programming is wiping of the existing memory.

Disabling MCLR only applies when the PIC is running, so you need to enter programming mode before the PIC can start running - if you don't enter programming mode fast enough, then it won't enter programming mode at all. However, as a user this isn't your problem, it's only a concern for the writer of the programming software (which is how I'm aware of it).

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