PIC - selecting wrong oscillator module

[DTSFA]

hi

I have a PIC16F690, I originally set config bits to HS (external oscillator),

but, this was mistake, as I am not using external crystal/oscillator,

the program still run though ?

( the config bits read back from PICKit = 0FF2 on original units programmed, confirming HS oscillator)

 

[T3STY]

maybe there's a fallback feature that runs the internal oscillator if the external one is inactive. You should read the datasheet to know more about the oscillators related to your PIC.