AVR-Chat

At 12:10 PM 7/04/2006, you wrote:
>         Would you please post the routine you used to write to the EEPROM?

All your precautions will come to nothing unless you
remember to turn off interrupts whilst writing to the
EEPROM. It will work most of the time / sometimes but
you are likely to get write errors if an interrupt happens
during the write cycle.
Here is my EEPROM write routine in assembler (sorry don't do C :-) )

;Put 1 byte in temp to address pointed by Z.
put_ieep_byte:
         sbic    EECR,EEWE               ;Wait for completion of previous write
         rjmp    put_ieep_byte
         cli
         out     EEARH,zh                ;Set up address (in Z ) in 
address register
         out     EEARL,zl
         out     EEDR,temp               ;Write data (temp) to data register
         sbi     EECR,EEMWE              ;Write logical one to EEMWE
         sbi     EECR,EEWE               ;Start eeprom write by setting EEWE
         sei
         ret

Regards

John Samperi

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