controlling multiple functions with one encoder ?

[matrigs]

so i had this idea for some time to make a quite different design of a midibox than usually. the goal is to create a box that could handle 64 functions but it should be as small as possible (mainly for live using)

i didn't draw it yet so i try to show it with text.

_________________________________________________________________________________

ENCODER | SWITCH | SWITCH | SWITCH | SWITCH | SWITCH | SWITCH | SWITCH | SWITCH |

now, the linking to the DIN4X module would look like this:

ENCODER---------|

                        |____________________________________

                        |              |                    |                  |

                    SWITCH    SWITCH          SWITCH          SWITCH

                        |              |                    |                  |

                  INPUT 1        INPUT 2          INPUT 3      INPUT 4

is a connection like this technically possible?

this way the box has also another feature besides being very compact:

imagine playing a live set in ableton live with 4 channels, every channel has one lowpass filter stuffed at it's end. the first 3 channels are playing.

now you want to make something like this:

you want to cutoff the lowpass filter on the first 3 playing channels and when they are cutoffed you want to slowly punch in the fourth channel and then punch away the cutoff from the first three to make all 4 playing normally.

it would be nearly impossible to do this with a normal midibox where every function is bond to one knob because you would have for example to move 3 pots at the same time to just make the cutoff.

with my idea, you just switch the first 3 switches on the cutoff encoder, and the 4 on the volume encoder. easy ?

[Sinnsyk]

There is a way to control over 128 parameters with 16 pots, or 4, or 8, or whatever u like (max 64).

Check the MidiBox 64E tutorial  ;D

And well, this idea, in theory it should work right? Are the pins that are not in use at that moment (switch off) grounded? -> , they connect to an open switch...

[matrigs]

could you explain that grounding issue a bit further?

do they have to be grounded between the switch --- input or before the switch right after the encoder?

[matrigs]

and most important - how should they be grounded ?

[tos]

If I'm on the right track you need double, twostate switches.

EDit:

If you are really mad you can use some perverted switches that are like 3-state and connect like this:

1. all off

2. din1 -> bit1; din2 -> bit2

3. din1 -> bit2; din2 -> bit1

Then you can select what control is beeing increased and which one is decreased.

I've done something similar with one pot that is producing two separate midi messages which are then controlling two sliders [wet & dry]

connection.GIF

[Sinnsyk]

Well, if u connect an encoder through the switch, there is no problem when the switch is on. But if you put the switch to off, the contact with the DIN will not be grounded, and it could give random midi-messages. So, perhaps a 2 way switch, that connects the DIN to the ground when turned off, could solve the problem.

But, do you have some testing materials? Or do you have to order all your parts? If u can test, I would say, try it all ;)

[stryd_one]

Uhm maybe I missed something but why not just do this in software?

One encoder, four momentary switches which 'patch' the encoder to four functions... why not add four LED's to show whether the encoder is patched for that controller.

[matrigs]

stryd: i didn't know wbout such a feature - most of the "professional" midiboxes aren't able to do something like this. is it easy to program the mios that way?

i'm a really electronic-noob, so could someone please please explain further this grounding problem? what is this about and why would i get random messages?

[matrigs]

ah one moment i think i got it now - so you talk about a situation when i have ALL switches off and the encoder is completely bridged away from the din module right??

i hope yes :D

so actually as long as i leave at least one switch open everything should function ok right?

[matrigs]

stryd can you help ?

[stryd_one]

To simplify, when the wire is grounded, there is a stable signal, because the circuit is completed, and all the electricity has somewhere to go.

When it is 'floating', then it picks up interference, just like your car or TV antenna would. That interference is measurable by the core module, so it is converted into MIDI. It's not good.

As for the 'professional' midiboxes... They can't touch TK's design :) It would only be a small change to the firmware, if you have some ASM or C experience it will be very easy.

[stryd_one]

Ahh about this grounding issue.... I should have read the whole thread before I replied. Don't confuse AIN's with DIN's.

[matrigs]

"Don't confuse AIN's with DIN's."

huh ? now i'm really confused... so is there a problem with dins or is this just ain related?

my god the day i will turn a knob and it will send some proper midi will be the greatest day of my life....

[tos]

It aint that hard, ju just connect some pot...wires...ain...core and there you are.

Anyway,

AIN - Analogue INput is used to connect pots(10KOhm),

DIN - Digital INput is used for pushbuttons, buttons, switches & encoders.

With AIN there is a problem if you leave connection open(, flying, unclosed circuit) bkz chip suceeds to read a resistance value that aint there and problem is that the reading is different every time(so you just get a bunch of random readings via MIDI).

[matrigs]

thanks TOS - got that !

but i still didn't get a proper answer for my quesion actually.

[henrygr]

Not sure of the question. What exactly do you want to do?

[matrigs]

okay once again :D

what i want to achieve is to have the ability to control, lets say 8 volume channels with just one encoder.

my idea for this was to pin one encoder to 8 din inputs at the same time, but with on\off switches between the enc and the input.

now - when i want to higher up the volume on 3 channels, i just switch on the three inputs of the desired volume channels and move the knob and it increases.... or at least i hope it increases.

this might be a quite wicked idea but in my case it would be quite comfortable.

[henrygr]

I see.

I don't see why the switches should not work in terms of breaking the signal, and as you are using a DIN module, there should be no random midi. (I'm taking it for granted that you are using a DIN module, and not connecting straight to the core).

You are using an mechanical workaround however to a solution that is possible to program.

So, to answer- yes, possible both as a mechanical and as a programmed utility.

You're best bet is to build your bits and bobs, leaving youself room to change how you constructed it. That way, you could play around with both possibilities.

Don't take what I say as any form of gospel. I just finished my first project and had an equally bizarre question.

MP

[Sinnsyk]

This can be done with software, and your hardware idea is probably easyer to construct.

But, the hardware version is not easily expandible, and with software, you can always change your programs and re-use your midibox on a different way or expand this system etc etc etc.

So, I would go for a software solution.

[henrygr]

Touche sinnsyk.

[tos]

It is simple and easy. Using software solution would lead to:

-basic reprogramming

-another row of dout-s [for showing states]

-more wires from core. [heh, like that ever represented a problem]

I'd go with software solution. Otherwise, you have a schematic in one of my prevoius posts.

I'm not sure about one thing, if you set the encoder to some higher sensitivity there is possibility that you get a increase or decrease by one unit when you switch on/off a channel.