add error message on invalid register

tweak comments

remove assembler from future work

remove unused fibo files

remove reference to incorrect J type encoding

It turns out I was actually using the same encoding as RARs after all.
Also, as described in the relevant issue on the RARs repo, it was the
correct style all along.

get fibo test case working

assemble lw and sw

assemble branches

assemble jalr

implement label resolution

got J types working, I think?

Either I am very confused, or RARS has at least one problem with it's J
type encoding, which means that riscv.awk disagrees with it (which also
breaks the relevant test cases). I have reported the issue upstream
here: https://github.com/TheThirdOne/rars/issues/89

assemble I, R, and shift types

start sketching out the assembler

add link to public inbox

add license

expand README

update README, add demo

implement dimp directive

implement lw and sw

add conditional branch instructions