This is why I'm bald... been ripping my hair out trying
to figure out this problem.  At first, I was not waiting
for EEIF to be set and noticed that data was not getting
written to the EEPROM.  Then, I added the 3 lines to wait
on EEIF set and get an odd result -- when the routine
gets called, it works some times and other times it hangs
-- the code just freezes.  (No WDT btw).

I've checked (prior to waiting on EEIF) with the simulator
and it works there.  Also verified that it's getting the
right values for the data and location.  The way I see it,
no matter what is passed in, this routine should work,
right?  It should not hang.  And most of the routine is
from the datasheet.

I do have TMR0 interrupts occuring, but that should not
hang this routine, should it?  Yes, I do save and restore
W & STATUS in the ISR.

Anyone have clues as to what may be happening?

Cheers,
-Neil.


        ;------------------------------------------------------
        ; Write data (in EEPARAM) to EEPROM location (in W)
        ;------------------------------------------------------
SetEEData:
        bsf     STATUS,RP1      ; Bank 2
        bcf     STATUS,RP0      ; Bank 2

        movwf   EEADR
        movf    EEPARAM,W       ; Data to be stored
        movwf   EEDATA
        bsf     STATUS,RP0      ; Bank 3
        bcf     EECON1,EEPGD    ; Point to data memory
        bsf     EECON1,WREN     ; Enable writes
        bcf     INTCON,GIE      ; Disable interrupts (if enabled)
        movlw   H'55'           ; Special seq
        movwf   EECON2          ; ...
        movlw   H'AA'           ; ...
        movwf   EECON2          ; ...
        bsf     EECON1,WR       ; Start write operation
        bsf     INTCON,GIE      ; Enable interrupts (only if being used)
        bcf     EECON1,WREN     ; Disable writes

        bcf     STATUS,RP1      ; Reset to bank 0
        bcf     STATUS,RP0      ;

WaitEEWriteComplete:
        btfss   PIR2,EEIF
        goto    WaitEEWriteComplete

        return

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