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Altera_Forum
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15 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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15 years ago

with

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unsigned char a=IORD(componenet_base,0x10)

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The CPU will do one 32-bit read access to the component's register 0x10, which the switch fabric will change into 4 8-bit read accesses at registers 0x40,0x41,0x42 and 0x43 (notice the register number shift).

It's a lot easier to do a 32-bit data bus, even if you only use the low 8-bits. It will save you a lot of trouble.