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Altera_Forum
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11 years ago

Problem with reading DDR2 using Avalon MM template (Cyclone III)

Good afternoon, I configured the system which is reading out data from flash in DDR2 using nios. Further using Avalon MM template I read data from DDR2, and they are read with additional 00 bits. In what there can be a problem?

Data in flash: 01 00 9F 02 FF FF FF FF ...

Read data in flash (Nios): 1 0 159 2 255 255 255 255 ...

Write data in DDR2 (Nios): 1 0 159 2 255 255 255 255 ...

Read data in DDR2 (Nios): 1 0 159 2 255 255 255 255 ...

It's OK.

Read data using Avalon MM temoplate (SignalTap II)

http://www.alteraforum.com/forum/attachment.php?attachmentid=10032&stc=1

Project: https://yadi.sk/d/ijojrj8ke9inw

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    I edited a post, and it was lost...

    The system which reads flash is configured and writes in DDR2 using nios. Works well. And here using avalon mm master we read DDR2, reads with additional 00 bytes. In what there can be a problem?

    Basic data in flash 01 00 9F 02 FF FF FF FF...

    Read data from flash (nios) 1 0 159 2 255 255 255 255...

    Read data after record in DDR2 (nios) 1 0 159 2 255 255 255 255...

    Read data from DDR2 (signal tap II), using Avalon MM master

    http://www.alteraforum.com/forum/attachment.php?attachmentid=10036&stc=1
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    The system which reads flash is configured and writes in DDR2 using nios. Works well. And here using avalon mm master we read DDR2, reads with additional 00 bytes. In what there can be a problem?

    Basic data in flash 01 00 9F 02 FF FF FF FF...

    Read data from flash (nios) 1 0 159 2 255 255 255 255...

    Read data after record in DDR2 (nios) 1 0 159 2 255 255 255 255...

    It is good

    Read data from DDR2 (signal tap II), using Avalon MM master

    https://www.alteraforum.com/forum/attachment.php?attachmentid=10039