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resistive sensor versus potentiometer analog board
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resistive sensor versus potentiometer analog board

by THW_Mark on Wed Aug 29, 2007 6:40 am

Hi there,

i've been searching the internet for several days now, to build a ultra-compact midi controller. Doepfer in Germany produces a similar product to Midisense, but the controlling software is less adjusted to calibrate resistors and the price is fairly high (starting with 75 euro, 100 USD).

MidiSense seems to be what i am looking for, i just wonder what the difference in implementation is between the analog board that is not yet released and the resistive sensor board. A sensor is just another type of potentiometer, isn't it?

Anway, i want to implement a touchpad or multiple touch-sliders into a small controller. A midi signal should only be send when the device is touched or released.

Is the actual board enough for me, or is it better to wait? Do you have an eta when the new board is ready?

THW_Mark
 
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by adafruit on Wed Aug 29, 2007 4:07 pm

the analog board supports touch pads, the resistive board does not. i have to do ANOTHER revision of the PCB, i'm sending it out today. do you have a source for the touch pads? those are the most expensive and difficult to get parts. i can tell you whether they are compatible.

adafruit
 
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by THW_Mark on Thu Aug 30, 2007 11:28 am

thanks for your quick reply!

I was thinking of using one of these: http://www.voti.nl/shop/p/S-Touchpad.html for example. It is just an ordinary pc/laptop pad with the ps/2 connector cut off. If it doesnt work, a direct connection to the pad. (I guess it has 2x2 wires leading there?)

Alternatively, i was thinking of opening an old/broken korg kaoss pad with a working touchscreen.

THW_Mark
 
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Location: Delft, Netherlands

by THW_Mark on Thu Aug 30, 2007 11:34 am

hmm according to this datasheet http://www.voti.nl/docs/touchpad.pdf and this website http://instruct1.cit.cornell.edu/course ... chpad.html

it seems there is only a ps/2 signal going out... which probably doesnt work too well... hmm

THW_Mark
 
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Location: Delft, Netherlands

by adafruit on Thu Aug 30, 2007 12:56 pm

yeah, thats rather complex :(

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by THW_Mark on Sat Sep 01, 2007 5:15 am

ah well, it is not like you can loose a fortune on it :P I also have an old psion 5mx here with touch screen, could try to rip that one as well..

THW_Mark
 
Posts: 36
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Location: Delft, Netherlands

by THW_Mark on Fri Dec 07, 2007 7:19 am

this looks like a REALLY nice solution http://www.spectrasymbol.com/linearposition.html . It's a bit like the qslide, but just a pure resistor as far as i can see without a controlling ic. Seems like a great solution for the analog input board to me, its just that i need to find a retailer... I requested a sample from the site, hope they can send me a resistor to test it. I will keep you all informed.

THW_Mark
 
Posts: 36
Joined: Wed Aug 29, 2007 6:33 am
Location: Delft, Netherlands

by THW_Mark on Fri Dec 14, 2007 4:12 am

bump bump... when will the a/d board be ready? :oops:

THW_Mark
 
Posts: 36
Joined: Wed Aug 29, 2007 6:33 am
Location: Delft, Netherlands

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