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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...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

yea my data bus is 8 bits wide!! is this problem independent of the size of the variable we assign IORD to ? for example whether we use:

""unsigned char a=IORD(componenet_base,0x10)""

or

""int a=IORD(component_base,0x10)""

the cpu does 4 read actions? (assuming the cumponent's data bus width is 8) ?

another questions : my compent has an 8 bit address bus. how is my 8 bit address mapped into the 32 bit Nios address bus ? the 32 bit address is truncated to an 8 bit address bus?