Re: MISC-d Digest V99 #70
In message <199907121635.LAA05465@rgate2.ricochet.net>, Jeff Fox
<theFox@UltraTechnology.com> writes
[snipped]
>But consider branching.
>
>Word vs byte branching: We have word based branching only on the 5-bit
>instruction machines while ShBoom II with 8-bit opcodes opted for byte
>based branching so that you can branch to an arbitrary opcode. However
>extra cycles are added to branching. This is how I would understand
>the memory to work and this is what I heard. If someone knows more
>they are welcome to say so.
ShBoom II (PSC1000) can only branch to (32bit) cell boundaries, and not
to arbitrary byte opcodes. The branch instruction includes the branch
as a literal, and can be 1 2 3 or 4 bytes long, depending on its
position in the instruction group.
Cheers
--
Keith Wootten
