diy platter

[laurens]

Hi all, just wanted to know if anyone has in depth knowledge of how the platter on say a vci-100 works. What I am trying to ask is could it be replicated with a rotary controller from a different midi controller or is there something specific that makes it work.

I would love to somehow hack my bcr2000 or similar to have platters for seeking through songs. etc.

[charo]

the platter on the vci-100 is sending +1 or -1 information depending on what way the platter is turned. i suppose an endless rotary could mimic that but there is also the touch part of the platter that sends a different +1 or -1 message when the platter is turned with the touch part activated.

the bcr has some endless rotaries right? you could link song scrub or beat jump to one of those rotaries for track scrub right?

good luck.

[DvlsAdvct]

The platter on the VCI-100 sends six different signals. Three when "Vinyl Mode" is activated (On, then the back and forth, then off) and three when "Vinyl Mode" is not activated. The back and forth motion is just a +1/-1, which can easily be replicated by an endless rotary, but you would need a touch sensitive one, or a button to replicate the On/Off feature.

[BentoSan]

The VCI-100 jog basicly works by having a whole heap of small holes on a peice of metal that freely turns as you move the jog - its actually two circles of small holes. A light shines though these small holes and theres light sensors on the other side of the two cricles that detects the light. The faster the jog is spinning the faster the light sensors are turned off and on, the jog knows the direction its going because of the alternating messages which tells the cpu the direction the jog wheel are going.

There is also a touch sensitive sensor, when it detect that your touching the device it sends a signal off to the cpu, then when you take your finger off the signal also turns off so your the cpu knows when are and are not touching the jog wheel.

[kidfromkibbly]

There is also another sensor that is touch sensitive, when it detect that your touching the device it sends a signal off to the cpu then when you take turns this signal off so you the cpu knows when are, and are not touching the wheel.

Dude........ isn't English supposed to be your first language? ..........

[Fatlimey]

Look up "Quadrature Encoder" for an explanation on how a pair of out-of-phase bits can tell you which direction the encoder is being spun. The controller then counts the number of flashes in a timeslice and returns that as (signed number + 64), e.g.

65 - 64 = +2
64 - 64 = 0
59 - 64 = -5

That's how you know how fast and in which direction your platter has been spun.

[Kaon]

There is also another sensor that is touch sensitive, when it detect that your touching the device it sends a signal off to the cpu then when you take turns this signal off so you the cpu knows when are, and are not touching the wheel.

are you trying to break brains?

[BentoSan]

It was late and i was dead tired - edited it now to make sense

[laurens]

thanks all, think I will just buy one some time in the near future. Sounds a bit over my head to try and replicate.

[cmcpress]

didn't somebody round these parts make one with an optical mouse for like peanuts cash?

http://www.midibox.org/dokuwiki/scratchcontroller