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Altera_Forum's avatar
Altera_Forum
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13 years ago

SD card ip core: read block error with SDHC

Hello all, my Project is as below:

IP CORE SD CONTROLLER with SPI mode,

work with 2G SD card but not with card >= 4G;

The initialisation flow is all good, no problem.

The problem is:

With a card HC(4G), when I tell it to read a block beginning at 40 00 00h, it reads at 80 00 00 00h (512 times bigger);

but with a card non HC(2G), there is no such problem.

the API using is "sd_read_data_block( sd_card_info_struct* sd_card, char* data_buffer, alt_u32 read_address )"

Can someone help me with this? It drives me crazy:cry:

THX very much!

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    Problem solved, the difference between the addr of sdhc and sdsc is 9bits (512 times), because sdhc requires more space for the addr.

    so before reading a block, we should determine either it is hc or sc.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    Hi lylli007,

    I am having trouble when trying to read or writing data to a SanDisk Ultra 2GB class4 which is also an SDHC. Can you explain how you solve the addressing issue?

    Thanks.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    Hello lylli.

    Can i get the source for detecting the SDHC card. University IP will detect only 2GB cards..I have struck from 1 month .It will be a great help.