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Altera_Forum
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11 years ago

components base address and offsets

I know how to get the base address of each component in a NIOS II system "Qsys" or the "system.h" file. What I dont understand is what is the offset and how to get it. for example componen...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

IOWR_16DIRECT(BASE_ADDRESS, 2*(address),DATA); //write 16bits of 'DATA' to the component at 'BASE_ADDRESS' plus offset.

Data is 16bit so addresses on your 'address' bus are spaced 2bytes apart, hence multiply by 2 when passing to the write macro. The base address can be found in the "system.h" file in the Nios BSP.