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???
02/20/09 08:44
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#162587 - bootloader v6 is affected, too
Responding to: ???'s previous message
Lorenzo Cappelletti said:
it seems to me that function "Program Security Bit, Double Clock" (see [1] on page 27) of P89V51RD2's bootloader v7 contains a bug: it never returns when called via IAP interface.


I believe version 6 of the bootloader (the one NXP currently ships its MCUs with) is affected, too. The disassembled code shows:
047Ch   MOV  A,FST
047Eh   JB   ACC.3,04BFh
0481h   JNB  SCON.1,0481h
0484h   ORL  FCF,#40h
0487h   MOV  B4h,#55h
048Ah   MOV  B5h,#AAh
048Dh   MOV  B2h,#08h
        [...]
04BFh   CLR  A
04C0h   RET
 

The line in bold shows a infinite loop if TI (SCON.1) is not set.

Do you think I should file a bug to NXP? Does anyone know how to do it?

List of 9 messages in thread
TopicAuthorDate
Function "Program Double Clock" never returns in IAP mode            01/01/70 00:00      
   You should check carefully            01/01/70 00:00      
      I feel safe            01/01/70 00:00      
   bootloader v6 is affected, too            01/01/70 00:00      
      it's the same in v4 and v5, too            01/01/70 00:00      
         TI=1 workaround            01/01/70 00:00      
            3-rd party programming and thebootloader            01/01/70 00:00      
               bootloader self-upgraded to v7            01/01/70 00:00      
   IAP ?            01/01/70 00:00      

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