The manual for the PIC12F629/675 clearly indicates that the procedure
to write to the EEPROM is as follows:

; BUT, this WORKS at 5V, not at 3.3V
; write a byte in w EEROM @tmp
wreeerom:
    bank1
    clrf    EECON1
    movwf     EEDATA
    movf    tmp,w       
    movwf     EEADR
    clrwdt
    bsf     EECON1,WREN
    bcf        intcon,gie
    movlw    h'55'
    movwf    EECON2
    movlw     h'AA'
    movwf     EECON2
    bsf        EECON1,WR
    bsf        intcon,gie
    btfsc     EECON1,WR
    goto      $-1           ;5mS wait max
    bcf     EECON1,WREN
    clrf      status      ;bank 0
    return

; the following WORKS at 3.3V and 5V
; write a byte in w EEROM @tmp
wreeerom:
    bank1
    clrf    EECON1
    movwf     EEDATA
    movf    tmp,w       
    movwf     EEADR
    bcf        intcon,gie
    clrwdt
    bsf     EECON1,WREN
    movlw    h'55'
    movwf    EECON2
    movlw     h'AA'
    movwf     EECON2
    bsf        EECON1,WR
    bsf        intcon,gie
    btfsc     EECON1,WR
    goto      $-1           ;5mS wait max
    bcf     EECON1,WREN
    clrf      status      ;bank 0
    return
;
I spent many hours trying to resolve why this simple relocation of  BCF 
INTCON,GIE
allows the EEPROM to work at 3.3V as well. This is NOT an isolated case, 
I have 50
PIC12F629's and 10 PIC12F675's doing the same thing.

My interrupt is trivial:

;*********************************************************;
;  Tick interrupt
; Precisely 1.024mS with 4M Int RC Osc
;*******************************************************;
intv:
    clrwdt
    bcf        intcon,t0if
    incfsz    count,f
    nop
    bsf        flags,flg
    retfie
  

I think that the manual has one instruction out of its proper place. 
Anybody else notice
this?

--Bob
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