[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

word mismatch



Hi,

  I have a question about a very strange bug. I have 2 PowerPc boards connected by a PCI bus. One has a Tundra Qspan2 bridge (the add-on), the other has a IBM CPC700 bridge (the monarch).

  From the monarch board, I write to the RAM of the add-on card. More than 1 Mb are written to the RAM. I use a loop : 4 32 bits words are written and then these 4 words are read just to check. There is no problem.

  But, when I check all the add-on card's RAM once again from the monach board, there is a mismatch on only one word. No need to say that nothing writes at it's adress during the second check.

  Does anyone has a idea ?
 

from monarch board (image base is 0x80000000, translated base is 0x00100000)

8001ffe0:  94 21 ff f8 7c 08 02 a6 90 01 00 0c 80 04 00 00   *.!..|...........*
8001fff0:  2c 80 ff ff 7c 69 1b 78 00 01 00 00 41 86 00 2c   *,...|i.x....A..,*
80020000:  3d 60 00 13 80 04 00 00 7c 80 48 00 40 86 00 10   *=`......|.H.@...*

from add-on card :

0011ffe0:  94 21 ff f8 7c 08 02 a6 90 01 00 0c 80 04 00 00   *.!..|...........*
0011fff0:  2c 80 ff ff 7c 69 1b 78 7c a3 2b 78 41 86 00 2c   *,...|i.x|.+xA..,*
00120000:  3d 60 00 13 80 04 00 00 7c 80 48 00 40 86 00 10   *=`......|.H.@...*
 

Thank you

Best regards,
Mathieu Berland