Analogue-sequencer

Hi Julian, 

> Using the recommended alpha pots, and...
> 
> Sometimes when a pot is right on the border between two 
> (digital) values, you may be working on something else and 
> the screen starts 'flickering' with data from the pot, as it 
> does when you intentionally change a value.

Er, that's what I meant by 'ghosting'. Sorry if that wasn't clear...

To give you a bit more background...
The analogue to digital convertor scanning the P3 pots has an 8 bit range,
but only 7 bits are needed at most for midi values.
So the original pot scan code prevented ghosting/flickering between adjacent
values by only flagging the pot as 'changed' if the 8 bit value moved by 2
steps or more. Once this was divided down to 7 bits, it meant the values can
still step by 1.
It seems that in some cases a little bit of extra noise pick up somewhere
might mean the pot moves enough to trigger a 'change' even though the pot
hasn't been moved physically.
The updated code now only flags a pot as 'changed' if the value is different
from the previous value for 2 scans.
This seems to eliminiate extraneous noise pickup.

Cheers,
Colin f