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Altera_Forum
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16 years ago

How the avalon mm slave "address alignment" works?

Hi everyone I use avalon mm slave port with conduit to interface a 16bits peripheral, but everytime when i READ the peripgheral, the data readback can not in correct address when inspected in...
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Altera_Forum
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16 years ago

Given that the nios2 cpu always does 32bit memory accesses, and that these get converted into two 16bit cycles to access a 16bit target, it might be worth making your peripheral have a 32bit interface and just ignore the high bits?

The 32bit MM bus doesn't have address lines for the bottom 2 address bits, writes use 4 byte enable lines, and (IIRC) reads are always 32bit.

It might be that the ADR0 line corresponds to value 4.