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Altera_Forum
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16 years ago

transfer from nios to 64-bit component

Hello, I am currently working on my own slave component. I've written and tested the 32-bit input version and it worked well. Now I have 64-bit input version. I know that nios cpu handles 32-...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

The valid cases are all those where the access has the same alignment as it's width.

For a 64 bit slave, the bytenable signal is 8 bits wide and the following valid cases.

64 bit accesses (0x0 to 0x7):

1111_1111

32 bit accesses:

0000_1111 (0x0 to 0x3); 1111_0000 (0x4 to 0x7)

16 bit accesses

0000_0011; 0000_1100; 0011_0000; 1100_0000

8 bit accesses

0000_0001; ...; 1000_0000