> Subject: [PIC] 16F877 works only when pulldown to ground with resistor
>
> Hi,
> Do any kind soul have any ideal why my 16F877 work only when I pulldown all
un-used port to ground?
> I used a 10k resistors to do that. Both VDD & VSS are connected and Pin 1 to
reset. Chip running at 4Mhz.

I thought someone else would have mentioned it, but if you have Low Voltage
programming turned on, then RB3 has to be held low for the chip to operate. If
it is not low then you are in program mode.

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