I'm working with a PIC18F4525 and hoping to use the INTOSC @ 8Mhz with
the PLL bumping it up to 32Mhz.

It doesn't seem to work as it should...

First of all it seems like every time I try to use an INTOSC it's an
evening of struggle to get it to be stable. I wind up using the same
settings I did to begin with, but that's another story.

I have INTOSC running at 8Mhz just fine, but if I add a

bsf		OSCTUNE,PLLEN

One of three things happens with no apparent pattern

1. (Most of the time) Nothing changes, the LED continues to blink at
the same rate
2. The LED doesn't blink at all
3. The LED blinks 4x _slower_

According to the data sheet the requirements for PLL is that the OSC
configuration bits are set to use the INTRC with or without the clock
out, and the INTOSC has to be running at either 8Mhz or 4Mhz. I have
fulfilled these two requirements.

So here's all the relevant code...

	movlw	b'01110000'
	movwf	OSCCON
	bsf		OSCTUNE,PLLEN

I've also tried it in C with the same result:

  OSCCON = 0b01110000;
  OSCTUNEbits.PLLEN = 0b1;

I've tried setting the PLLEN bit after a delay, but that doesn't seem
to help either.

I see nothing in the data sheets or errata to suggest that I am doing
something wrong, but it just doesn't work correctly.

Thanks for any tips, perhaps I just shouldn't be trying to use INTOSC
for these speeds?

~Jake B

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