AVR-Chat

At 07:15 PM 6/7/2005, Dave Hylands wrote:
> > I'm pretty sure this table is right.
>
>And what I often do is write a little C program which I compile on my
>PC that I use to generate source code for tables like this (or CRC
>lookups etc).
>
>I typically include the C program #if 0'd out in my source file that
>uses it as a way of documenting how the table was actually created.

A good idea!

>If you don't want to use 256 bytes for the lookup table, you could
>also do a pair of (or a single) 16 byte lookup table which flipped 4
>bits. Now you have a pretty wide execution time/space tradeoff and you
>can picks what's appropriate for your project.

I don't really need it, I was just musing about it.
We have rotate and swap instructions, but not "flip" (or whatever 
you'd call it.)