Great question because the answer is somewhere between 6 and 7 bits - lol.
But seriously, the digital pot's are either 100 or 128 bit resolution.
Can't remember exactly, I'll check the doc's tonight.
The code is going to be interesting because the wipers are clocked up
and down and there's no way to read their positions. So the position
has to be stored by the CPU in memory and then the pot's have to be
clocked up and down according to the difference between existing set
position and the new required position. These little 8 pin chips are
really designed for car radio volume controls or similar applications.
The challenge will be to make sure that the code keeps the pot's very
responsive while also not slowing down things when a big pot sweep
change occurs. So let's say we send a MIDI controller that sweeps from
0 to 99 in one message then we'll have to slow the sweep down a bit
perhaps only clocking up 10 pot positions in a single interrupt cycle.
So ten interrupts will be required to get the pot to it's final end
position.
That should be quite OK because the joystick A/D conversion code works
in the same way where it takes 16 hardware interrupts to do a full
conversion of both the X and Y axis. In this configuration, I still
can't "hear" any slowness in the MG or bend joystick responsiveness.
Mike.
--- In korgpolyex@yahoogroups.com, Atom Smasher <atom@...> wrote:
>
> somewhat off topic, but what will be the resolution of the software
> control over the hardware mods? 6 or 7 bit?
>
>
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