12F675 / MCLR use

[Acetronics2]

Never trust the state of any I/O on Power-Up - regardless of what the Datasheet says.

Always preset your I/O's within your program to what you want them to be as one of the first things you do when initialising the PIC.

Hi, Mel

You do know the only one I trust in, is you, Mel ... ( Violins [ON] , Crooner [ON], Rose Petals drop [ON], Champagne [ON] ... )

I just think you missed my two I/O Config lines ... ( Was late, eh ...)

I must tell it ALSO affects GPIO.4 ... so, I have to try adding a little PAUSE after those CONFIG Lines, I smell a Power on little issue ... That make BUTTON read a low level when power up ...

OR May be a " HIGH GPIO.0 " Command before the first BUTTON Command to ensure the High Level ...

Testing a HIGH level for Button1 pressed is to also an idea ( some capacitive effects on GPIO.0 ??? ... despite it has no load but a Pullup resistor !) ...

But, that's not something " normal " ...

Alain

[Acetronics2]

As I smelled ...

Adding a little PAUSE 50 ( 40 is not enough ! ) just past the I/O config Lines solved the issue ...

HIGH GPIO.0 didn't work ...

Alain ( bug killer ...)