Working with HEF

[mpgmike]

I am working with a PIC16F1619 that uses High Endurance Flash instead of the conventional EEPROM. I have pored over the data sheet as well as AN1673, a MicroChip Application Note specifically on the PIC16F1XXX processors and the HEF (AN1673 includes a .c and .h file with everything coded in C). Anyways, here's what I got so far:

Cyls        var     byte
Start:
GOSUB Write_HEF
GOSUB Read_HEF


Write_HEF:
ASM
    BANKSEL PMADRH
    MOVF    0Fh,W
    MOVWF   PMADRH                          ;PMADRH = $0F, 1st HEF Address is 0F80h
    MOVF    80h,W
    MOVWF   PMADRL                          ;PMADRL = $80
    BCF     PMCON1,CFGS
    BSF     PMCON1,WREN
    BSF     PMCON1,LWLO
    MOVIW   _Cyls
    MOVWF   PMDATL
    
ENDASM
    GOSUB UnlockHef
@   BCF     PMCON1,LWLO
    GOSUB UnlockHef
@   BCF     PMCON1,WREN   
RETURN


Read_HEF:
ASM
    BANKSEL PMADRL                          ; Select Bank for PMCON registers 
    MOVLW   0x80h                           ; 
    MOVWF   PMADRL                          ; Store LSB of address 
    MOVLW   0x0F                            ;
    MOVWF   PMADRH                          ; Store MSB of address
    BCF     PMCON1,CFGS                     ; Do not select Configuration Space
    BSF     PMCON1,RD                       ; Initiate read
    NOP
    NOP
    MOVF    PMDATL,W                        ; Get LSB of word
    MOVWF   _Cyls                           ; Store in user location 
    MOVF    PMDATH,W                        ; Get MSB of word
    MOVWF   _b0                             ; Store in user location
ENDASM
RETURN


UnlockHEF:
asm
    BANKSEL PMCON2
    MOVLW   55h
    MOVWF   PMCON2
    MOVLW   AAh
    MOVWF   PMCON2
    BSF     PMCON1,WR                       ; set WR bit
    NOP
    NOP
endasm
RETURN

What am I missing?

[richard]

Cyls        var     byte
Start:
GOSUB Write_HEF
GOSUB Read_HEF


Write_HEF:
ASM
    BANKSEL PMADRH
    MOVLW    1Fh
    MOVWF   PMADRH                          ;PMADRH = $1F, 1st HEF Address is 1F80h
    MOVLW   80h
    MOVWF   PMADRL                          ;PMADRL = $80
    BCF     PMCON1,CFGS
    BSF     PMCON1,WREN
    BSF     PMCON1,LWLO
    ????  MOVIW   _Cyls  see below
    MOVWF   PMDATL
    
ENDASM
    GOSUB UnlockHef
@   BCF     PMCON1,LWLO
    GOSUB UnlockHef
@   BCF     PMCON1,WREN   
RETURN

What am I missing?

start here I think
1st HEF Address is 0x1F80h not 0x0f80


MOVIW _Cyls
this won't work that's an indirect load of wreg but a fsr has not been loaded or selected

BANKSEL _Cyls
movf _Cyls,w  
BANKSEL PMDATL
movwf PMDATL
clrf      PMDATH  ? ;  a write is 1 word

does writecode not work for these chips ?

[mpgmike]

Richard, that is obvious when you work with Assembly a bit more regularly than I do. Thank you. I'm on a business trip right now, but should be able to try it later this week.

[richard]

have a look at this

saves 1 to 32 vars to hef

[mpgmike]

Many thanks. I'm back from a week long business trip and am getting back in the groove of things.