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Altera_Forum
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11 years ago

Avalon 8 bit with Nios 32 bit possible?

It is possible to create a component (ex. UART) with avalon MM slave interface with 8 bit data width and use it with Nios II with 32 bit bus? I tried and compile fine but Nios II don't start on re...
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Altera_Forum
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11 years ago

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If you have an 8bit slave you'll get a bus width adapter added than generates 4 cycles to your slave for every access done by the nios.

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This is incorrect (perhaps old?) information.

8/16/32-bit accesses from NIOS via IORD/WR_xxDIRECT() behave like you would naturally expect against an 8-bit slave: you get 1, 2, or 4 transactions.