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Altera_Forum
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14 years ago

Custom Component Address Mapping

I have a custom component with a 8 bit ADDRESS bus. it is mapped in my hdl code this way : .... if (read & (address==8'h01)) readdata<=2; .... In my SOPC builder system i...
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Altera_Forum
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14 years ago

PIOs are always 32 bits. If you create a 8-bit PIO it will just use the low 8 bits of the register, and the CPU will just perform one read.

Nios 2 is a 32-bit CPU, and assumes it's data bus is 32 bits wide. When you connect 16 or 8 bit peripherals to it then some non optimal side effects can appear, due to the way the CPU accesses the data bus.