Hi Sergio,

That's pretty similar to what I've sketched out in many parts. I
haven't tried mine as I'm waiting on PCBs. I do have a few questions
though:

> // from what I've read, there is no advantage to storing
> // chan_buff[][7] as BAM_buff[0] so using left shifts in the
> // following code just makes things much more complicated for
> // no added benefit

I don't understand this comment. Do you mean using left shifts at all,
or just in the init section?

> void set_channel_value(unsigned char indx, unsigned char val)
> {
<snip>
>         // disable interrupts
>         di();
>
>         BAM_PORT =3D BAM_buff[bit_pos];
>
>         // enable interrupts
>         ei();
> }

Why are you stuffing the output port in the set_channel_value()
function? I would have thought it should only happen in the ISR?

>         if (bit_cnt =3D=3D 0)
>         {
>                 // don't calculate bit_mask from bit_pos in the ISR as
>                 // as variable shifts are expensive and unnecessary in
>                 //  this case
>
>                 if ((bit_mask & 0x80) =3D=3D 0)
>                 {
>                         bit_mask <<=3D 1;
>                         bit_pos++;
>                 }
>                 else
>                 {       bit_mask =3D 1;
>                         bit_pos  =3D 0;
>                 }
>
>                 bit_cnt =3D bit_mask;
>
>                 // I'm assuming the output pins are defined as a group at=
 compile time
>
>                 BAM_PORT =3D BAM_buff[bit_pos];
>         }

Ok, I understand that you're using a counter variable to know when to
trigger the next output. I need to reread this a few more times to get
a handle on the logic, but I get that you are essentially comparing a
mask to a counter as you're calling the BAM ISR routine based on a
regular timer interrupt. I was considering dedicating a timer to this,
and loading specific values into it. It means my ISRs will be longer,
but it does mean I can tune the timings a bit more. I'm not entirely
sure which is the best way to go to be honest.

Thanks!

Josh
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