Help PIC16C65 -MCLR

Aaaargh! Rush job and my brother has suddenly stopped writing firmware and is beating his head against a PIC16C65 problem <angst>
"The reset line (-MCLR) is being held partly down by the CPU so the CPU never runs".
Does anyone know why this is? Or maybe someone could point me at a PICky newsgroup where I can get an answer?
I already had to dash over there with my programmer this morning when his went tits up at exactly the wrong moment, besides, it would be kind of impressive if lil'ol'me sorted out something before he did.
best regards
Robin G Hewitt
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AFAIK the PIC never drives the MCLR line - it is an input ! Normal practice is to tie to VCC with a wire or resistor. I suppose if you use a large enough resistor you might have trouble with leakage (or slow rise time on power on).
Dave

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On Mon, 2 Feb 2004 12:24:34 -0000, the renowned "Dave Garnett"

Or bro has fried that particular chip.
Best regards, Spehro Pefhany
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Hi Spehro Pefhany
Good point, he tried them both but I just ordered a spare :o)
best regards
Robin G Hewitt
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If bro has MCLR connected to VCC, and tries to program it, he will apply VPP (12 v ?) to the vcc terminal and anything connected to it - which may be bad news for the device and/or the programmer ...
Dave

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VPP
bad
Hi Dave
He's programming with an EMP 11 programmer, the PIC is out of the board and it verifies okay. The reset circuit is a resistor, a diode, a capacitor and a switch, looks good to me. I'm sure he'll figure it out, I was just trying to save some time.
best regards
Robin G Hewitt
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