Greetings All,

I have tried to implement EEPROM writes on 16F84 at 3.2768 Mhz using =
Charles Manning's Assembler, KIT 81 and PICALL. WDT disabled, Power up =
timer enabled. GIE and TMR0 enabled at initialization

Once the subroutine below has been called all subsequent reads to any =
EEPROM location returns the '9' (used as the write test data).  However, =
if it is put thru a power down/up cycle then subsequent reads return =
values as expected. ie the '9' is in the right place and everything else =
as it should be.

If I rem out the 6 lines as shown '*', all subsequent reads are normal.

Anyone any idea where I am going wrong.

Justin

RamToEeprom ;*************************************************
                        movlw    EEFaceTens     ;Address where data =
written
                        movwf    EEADR,f           ;move it to the =
address reg
                        movlw 9                         ;just some test =
data
                        movwf EEData,f              ;move it the Data =
reg=20
ShiftNextRamByte                                  ;Sub will later move 5 =
bytes
                        bcf GIE                          ;Disable all =
interrupts
                        btfsc GIE                       ;was it =
successful
                        goto ShiftNextRamByte   ;no, try and set it =
again
                        bsf RP0                         ;switch to bank =
1
                        bsf WREN                     ;Enable EEprom =
writes
                        bcf EEIF                        ;clear the write =
success flag=20

*                       movlw 55h,w                   ;55 cause manual =
says so
*                      movwf EECON2,f            ;write it to the =
control reg
*                      movlw 0AAh,w                ;AA cause manual says =
so
*                      movwf EECON2,f            ;write it to the =
control reg

                      bsf WR                           ;this initiates =
the write
                      bsf GIE                           ;re-enable =
interrupts
                      nop                                ;just in case =
it needs some time
*WaitForWrite   btfsc EEIF                      ;has the write finished
*                      goto WaitForWrite           ;no, then wait some =
more
                      bcf EEIF                         ;clear the flag=20
                      bcf WREN                      ;clear WREN when not =
writing
                      bcf RP0                          ;switch back to =
bank 0
=20
                      return
;RamToEeprom End Sub

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