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Altera_Forum's avatar
Altera_Forum
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14 years ago

IOWR Macro to access 64-bit QDRII

32-bit Nios II is intended to access a 64-bit QDRII using IOWR and IORD macros. Can anyone tell me how should I do this? Noticed that now the access is as such:-

32-bit nios ii writes to 64-bit qdrii and 64-bit qdrii writes to 72-bit afi

Thanks,

Carid

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Just a guess: I know that there is IORD_32DIRECT(), maybe such macro for 64bits? :)

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    The Nios CPU always sees its data space as 32 bits so a 64-bits read/write operation will have to be split up into two 32-bit operations.