876A startup issue with PortC

[peterdeco1]

I had the same problem with a 16F819. I turned off the powerup timer & it went away.

[paul borgmeier]

PORTC = xxxxxxxx on POR or BOR (see datasheet as Skimask would say)
where x = unknown (versus a known 1 or 0)

Your simulator is probably set to let unknows be high since it has to be one or the other.