Forum Discussion

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

Nios ii Instruction Macros

Can anyone explain to me how macros of the nios ii instructions (addi, subi, movi, ...) are interpreted in computer system vhd file? Do their entities and definitions exist in the vhd file of the ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

The internals of the cpu are encrypted and hidden.

You can see the logic of the custom instruction decoder and mux in one of the randon windows during synthesis.

Basically all the instruction logic blocks are given the entire input info (32bit instruction word and two 32bit register values), calculate their result, and a big mux selects the correct result and 'write-back' enable.