AnsweredAssumed Answered

DATA EEPROM area - problem writing byte

Question asked by WoRo on Jul 12, 2011
Latest reply on Jul 22, 2011 by brazov.ajeje
Hi experts,

in my application I am trying to write a single byte to an address in the DATA EEPROM area immediately after disabling "the DATA area write protection by writing consecutively .. MASS keys to the FLASH_DUKR register".
--> But writing will be ignored!!
 
Inserting at least one instruction after writing the MASS keys solves the problem.

Code:
...
     FLASH_DUKR = 0xAE;
     FLASH_DUKR = 0x56;
     *DATA_EEPROM_destination = char_value; 

From the Disassembler:
.......
eep.c:226        FLASH_DUKR = 0xAE;
0x8db2 0x35AE5064     MOV   _FLASH_DUKR,#0xae
eep.c:227      FLASH_DUKR = 0x56;
0x8db6 0x35565064     MOV   _FLASH_DUKR,#0x56
eep.c:231       *DATA_EEPROM_destination = char_value;
0x8dba 0x7B01         LD    A,(0x01,SP)
0x8dbc 0xF7           LD    (X),A
........

The problem does not to appear always, but I can't see any principle :o(
Any ideas???

Regards,
WoRo

BTW: can anybody help me? How can find related discussions by search function in this ****** forum???

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