Hi all,

Amongst all the other things on my plate right now, I'd like to make a
small library to do Bit Angle Modulation on some of my projects. I
made one years ago in assembly, but now I'd like to do it in XC8.

For reference, there are some great posts on BAM on the PicBasic forums her=
e:

http://www.picbasic.co.uk/forum/showthread.php?p=3D45597
http://www.picbasic.co.uk/forum/showthread.php?t=3D10564

Because the PIC will be doing many things, I am considering using a
high priority interrupt for the BAM, but keeping my high priority ISR
as small as possible (which is probably a good idea regardless). To
accomplish this, I want to create the 8 "slices" that I will output in
my main line, so that all the BAM ISR has to do is take that variable
and put it on the port.

My question is, what would be the best way to handle this in C? When I
did it in assembly I used a rotate (rotate right if I remember
correctly), then read the carry bit. But then I was also doing it at
the moment of outputting, so there was no intermediate stored
variable.

My current thought is to define a typedef that lets me access the
individual bits, then a bunch of if/else statements that check the bit
of the source value, and if it's a 1 set the bit of the corresponding
"slice" variable. This would result in a lot of if statements though,
so I'm wondering if there's a slicker way to do this.

I'm trying to avoid dropping into ASM to do this for a few reasons.

Any thoughts?

Thanks!

Josh
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