> Its been a while since I've had to code into page 1.  If you have an ISR
> being triggered by TMR0, such that it is always going into it, what
happens
> when you enter it from page1, make calls from the ISR into page0 then
return
> back to page1.

Nothing unusual as long as the interrupt routine saves PCLATH, does
whatever it wants with it, then restores it before returning.  There is
nothing magic about interrupt code.  The processor has no notion of being
"in" an interrupts.  All code is the same.

> Does the stack contain the fact that you started in page1, so will it
return
> ok back there or do I (should I) disable interupts when I am running
stuff
> in page1

The full 13 bit return address is always pushed onto the stack, just like
the manual clearly states.

> How deep is the stack for calls/returns?  This is on an 877 device

This is getting silly.  RTFM.


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