Bc2000 (for the BCF2000 & BCR2000)

--- In bc2000@yahoogroups.com, "Denis Gerage " <nedagg@...> wrote:
> The following questions arise because I see in bcmanager  resolutions
> window that it could be setted with higher numbers and I don't find /
> discover how to use it ... Maybe I'm missing something .

For general info on encoder resolutions, see "BC MIDI Implementation.pdf" (available from http://mntn-utils.110mb.com), section 17.3.
If I remember correctly, people have also discussed encoder resolutions in this forum, so you might try searching the message archive.

> which combination of resolutions and mode should you suggest in order
> a knob can perform the following tasks:
> 
> 1) control continuous parameters
> 
> I set 4 resolutions at 5 30 96 200 .

There are 2 aspects to these resolution settings:

1. The "basic granularity": this depends on the range of the parameter that the encoder is controlling: for a "normal" 7-bit controller value (0-127) the default resolution of 96 (i.e. 96 values per rotation (360 degrees)) is usually adequate. However, for a 14-bit CC/NRPN, a much higher value is appropriate, and for a small range (0-1, or 0-10) of course a much lower one.

2. Using different resolutions - i.e. setting different values for the four available resolutions at different speed ranges (R1, R2, R3 and R4). Of course, typically you would make the encoder take bigger value jumps when you turn the knob faster.
Frankly, I personally don't like this very much (I also don't like doing this sort of thing to my computer mouse), so I usually have R1=R2=R3=R4. However, this is completely a matter of taste - it would be interesting to hear other opinions on this.

> ( And I see you can go to 100.000 !!!

65535, actually...

> I'm lost which mode fits better ( abs ??? Rela14 bit ??? ) .

Normally absolute and absolute-14 are the modes to choose. The other ones are more "specialistic"; in general, not many receiving MIDI device support these. You just have to consult the documentation for your MIDI device. See "BC MIDI Implementation.pdf" section 16.3 for details on how all these modes work from the BCF/BCR2000's perspective.

> 2) Control increments of discrete parameters
> 
> If the above is too generic and I need a especific knob  to change
> filter types , which setup is better ??? How can I setup a knob in
> order its range  to cover all types of filter , with adequate
> speed/resolution  and mode types ?  Let's suppose there are 8 filter
> types to be selected

First of all, as I stated above, I personally would use only one resolution value (so 96 96 96 96, or 10 10 10 10, etc.).

Then, to determine this appropriate resolution, I would look at the range of values determined by the Value1 and Value2 parameters: I would probably want to select a resolution that is roughly the same as Abs(Value2-Value1): you then traverse the whole range from Value1 to Value2 in one full rotation.

In fact, the standard resolution of 96 more or less corresponds with the standard 7-bit range from 0 to 127. More precisly, 96 in this case means that you need slightly more than a full rotation to move from 0 to 127; so if you want to maintain that feeling, you could always keep the resolution perhaps 25% smaller than the range, so perhaps at 50 if the Value1/2 range is 0-63, etc.

In your example of 8 filter values it depends how these 8 values are encoded on the receiving MIDI device:
If they are spread out across the standard "full 7-bit" range from 0 to 127 (so 0-15 means filter type A, 16-31 type B, etc.), you have to set Value1 to 0 and Value2 to 127, and then a resolution of 96 seems appropriate.
However, if these 8 values are encoded "directly" (i.e. simply 0, 1, ... 6, 7), then you probably want to use a resolution of perhaps 10 or 20: in any case at 96 you would traverse the whole range from 0 to 7 in a fraction, which doesn't seem appropriate.

Hope this helps a bit,
   Mark.