How to turn off MCLR (16F819) ?

sorasit46 · Joined: 07 May 2007 Posts: 69

(Header ) #FUSES NOMCLR

I want MCLR pin (A5) can act as a regular digital input.
When low logic input, The chip will run unreliable, and will shut off on unexpectedly.

Please help.
Best regard

temtronic · Posted: Mon Apr 23, 2018 8:19 pm

You really need to show us your program, That PIC should support the fuse 'nomclr', however something else could be causing the problem you're having, like the WDT being enabled...shorted pins, ??

Jay

Ttelmah · Joined: 11 Mar 2010 Posts: 19546

Also, you have to be very careful when using the MCLR as a conventional input. It does not have any protection diode built in, and if the signal glitches above the supply (even quite a small amount), this can trigger the start of a programming cycle, and reset the chip. It is best to have your own external protection diode on the pin.