In your erase code, poll the WR bit for a write complete.  The eeprom write takes sometimes a few Msec to complete.

I would add this after you set the WR bit to start the write,

BTFSC EECON,WR     ;check the wr bit for a complete write

GOTO $-1                     ; if not complete poll again

The Pic will automatically set the bit to 0 after a successfully write.

Jamie

-----Original Message-----
From: tallevi21 [mailto:k...@rogers.com]
Sent: Sunday, August 03, 2003 12:01 AM
To: p...@yahoogroups.com
Subject: [piclist] Erasing EEPROM through Code

I am having a problem wiping the first 16 bytes of the EEPROM through
my code. I ran it through the simulator, it WORKS fine. But when I
burn it to the PIC, it only erases the FIRST location of eeprom and
that is all. So basically the proper registers are loaded with data,
and there is a loop to write each location of the eeprom with FF,
have I missed something here? Any ideas would be appreciated, thank
you.

PREPARE:
            CLRF EEADR      ;Clear EE address counter
            MOVLW 010h      ;Move 10h (16) to W
            MOVWF EEADRLEN  ;Move 10h (16) to counter
            MOVLW 0FFh      ;Move FFh to W
            MOVWF EEDATA      ;Move FFh to EEDATA     

BEGINWRITE:
            CALL ERASE   
              INCF EEADR, F                                   
                DECFSZ EEADRLEN
            GOTO BEGINWRITE
            RETURN

ERASE:
            BSF STATUS, RP0  ;Bank 1
            BCF INTCON, 7 ;Disable Interupts
            BSF EECON1, 2 ;Enable Write
            MOVLW 55h
            MOVWF EECON2     ;55h MUST be written to EECON2
            MOVLW 0xAA      ;to start write sequence
            MOVWF EECON2     ;Write AAh
            BSF EECON1, 1   ;Set WR bit begin write
            BSF INTCON, 7  ;Enable INT's
            BCF STATUS, RP0  ;Bank 0
            RETURN