AXiS-49 teardown

posted Mar 31st 2009 2:14pm by Eliot
filed under: digital audio hacks

cthruteardown

We touched on harmonic table MIDI controllers when [aris] was building one. [Ken Rushton] has one of C-Thru’s commercial keypads, the AXiS-49, and disassembled the device to show how it works. A PIC18F2450 microcontroller provides the USB interface and is connected to a dsPIC33FJ128GP310 digital signal controller which decodes the keypresses. The membrane buttons are made with two concentric graphite disks that touch gold contacts. The microcontroller measures the time between the two points contacting to determine the button velocity. monome button clones also use circular contact pads, but cannot calculate velocity because they only have one element.

[via Matrixsynth]

Comments [5]

tagged: c-thru, dspic33f, harmonic, harmonic table keyboard, ken rushton, matrixsynth, microcontroller, midi, monome, pic, pic18f, pic18f2450, teardown, usb

5 Responses to AXiS-49 teardown

Arthur says:

March 31, 2009 at 4:18 pm

Hey, not to be nitpicky, but one of the things that has bugged me about hack a day latley is the sheer amount of links in a article summary.

I ended up clicking on “Was building one”, “monome button clones” and “axis-49″ before finding the link that the title of the article references.

I think its great how much information you provide in an article summary, but sometimes its hard to find the juicy bits.

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nubie says:

March 31, 2009 at 4:45 pm

If I am befuddled I usually mouse over the links.

(The “VIA” link will show you where they got the info, and that link will usually have a better source link.)

It is kind of tough sometimes to find the link, but if you think this is bad you should try reading Dansdata :P

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Eliot Phillips says:

March 31, 2009 at 4:57 pm

Sorry about that. I think this post was problematic because the article is wedged between two other links.

We generally try to be very descriptive with our link text though. That’s why we used “disassembled the device to show how it works” instead of say “has one”.

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cynic says:

March 31, 2009 at 5:10 pm

Are those some unpopulated headers in the picture? Interesting.

I feel terribly dorky for perking up at the fact it uses two pics though. I’ll get around to my projects with them eventually.
I tell myself.

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TheYikes says:

April 1, 2009 at 2:30 pm

Anyone else notice that if you view the image for this article and scroll up and down a click with the mouse wheel repeatedly it give the illusion that the button pads are expanding and then contracting!

I know pointless really but i was kind wasted when i noticed it first!

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