Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Sign In with Twitter

Looking for Accelerometer/Header Info

edited January 2013 in Hardware

Hey folks, I've purchased an Omni/Accelerometer board and want to be sure I understand how to wire it correctly before I proceed. I'm a little confused about when to use particular headers generally, and specifically, which is used for the accelerometer. 

Ideally, I'd like to have two rows of knobs with a short fader in the bottom two rows. Alternately, since I can reverse the faders using Brain 2 configure, I could have the short fader in the top two rows and the 8 knobs in the bottom two. Would either configuration work with the accelerator.

Part of my confusion is that Section 4 of the Omni Board page on the WIKI (
http://wiki.lividinstruments.com/wiki/Omni_Board#Accelerometer_Configurations) lists four allowable configurations (4F8K, 4E4F4B, 4F8B and 4B4F4B). However, only two configurations refer at all to an accelerometer (section 3.7, 4B4F4B, and section 3.9, 8K4F). Both of these configurations have the short faders in the middle two rows of the board, which is what I really DON'T want.  (By the way, based on the pictures, shouldn't the 8K4F be referred to as 4K4F4K?) At any rate, nowhere in the WIKI does it say how you DO connect the accelerometer, only what do if you don't have an accelerometer installed. 


Any insight as to which headers are used and/or  WHY there are only certain configurations allowed with an accelerometer would be most appreciated!

Steve
Mercy College

Comments

  • http://wiki.lividinstruments.com/wiki/Omni_Board#4F8K_.284_Faders.2C_8_Rotary_Potentiometers.29

    This is a link for the 8k4f. This sounds like what you are looking for, and as you said, you can reverse the direction in brain config so the faders would be on top or bottom.

    "(By the way, based on the pictures, shouldn't the 8K4F be referred to as 4K4F4K?)"

    It seems properly named, maybe you are looking at a different configuration.

    Some insight:

    The limitations for the accelerometer omni board comes from the fact that the header titled "slide 4x30mm slide 4X60mm" already has 3 of its pins used up by the accelerometer.

    If the configuration in the link I posted will work for you, then please let me know if you have anymore questions to get it going!

    If you would like a different configuration, then please let me know and I will tell you what specifically can work and what can't.

    Hope this helps!

    -Mark

  • Mark, this is very helpful. Thanks! The link you posted to the 4F8K is what I need.

    The 8K4F configuration is found here:


    This is what I think should be called "4K4F4K."

    Anyway, I'll go ahead and populate the 4F8K and I'm sure I'll get it working just fine.  Just out of curiosity though, which three pins on the header are used for the accelerometer?

    Best,

    Steve


  • Pins, 7, 8, and 9 are used for the accelerometer.

    And that should be called 4k4F4k.. Thanks for pointing this out!

  • I've built the board. If I only connect one ribbon cable, the eight knobs are working fine via the "Pots 9–16" header. 

    Getting noise out of the Slide 4x30/Slide 4x60 header. I just see random controller numbers (including controllers that are not hooked up). On the Brain V2, analog inputs for slots 2-8 are jumpered with the small jumper boards. When I move the sliders, occasionally I'll see a set of values for cc's 0-3; most of the time nothing happens. Something's obviously wrong.


    Two questions: 

    I notice that on the Livid Builder v2 Omni Board Quickstart Guide  (4K4F4B),


    R2 and R4 are jumpered with a solder bridge. Is that something I want to do on this configuration (4F8K, with accelerometer)? When generally do I need to connect these?

    Also, there appear to be surface-mounted components on the accelerometer Omni board at SC1-SC4. I left these in place, assuming they are surface-mounted caps (and I did not mount thru-hole .01 µFd ceramic caps there). Is this right, or are they in fact surface-mount 0 Ohm resistors designed to short out wipers 1–4 (i.e., the four sliders)?

    Any insight is greatly appreciated.

    Steve


  • Steve can you send me a picture of the front and back of your board as well as a screen shot of the noise?

    My email is MDeMay at LividInstruments.com

    Hopefully I'll be able to assist you in trouble shooting!

  • Hey, in case this helps anyone else, I'll let you know the solution I came up with here:

    Not finding much info on the Livid Wiki, I looked for a similar surface-mount accelerometer. Not sure if I found the one Livid installs on the Accelerometer Omni Board, but it was a similar size and used an LF-14 case style. Downloading the data sheet, I determined that the outputs of that chip were pins 7, 8 & 9. Using a continuity tester and a second omni board, I determined that these pins on the accelerometer would be connected to the square pads at the three jumper locations SW-X, SW-Y and SW-Z. Furthermore, the center pad (round) in each jumper group had continuity to pins 7, 8 & 9 on the output header (called "Slide 4x30mm/Slide 4x60mm"). The outer round pad had continuity to ground. Without an accelerometer, you'd normally solder a jumper connecting the round pads of each location (SW-X, SW-Y and SW-Z), thus grounding out the unused accelerometer pins.

    When you do have an accelerometer, you are supposed to connect the square pads to the center round pad, thus connecting the accelerometer to the pin header. This wasn't exactly clear from the wiki.

    The problem with the board I had, is that Pin 1 of the pin header (Ground) was shorting to Pin 2 of the header (the Vcc supply voltage). This took quite a while to figure out. During manufacture, someone surface-mounted 0-Ohm jumpers across SC1, SC2, SC3 and SC4. Perhaps the intention was to ground out the faders and just use the pin header for the accelerometer (???), who knows... at any rate it made faders 1–4 entirely inoperable. I heated up the 0-Ohm jumpers until they slid off the board and suddenly the faders began working again. 

Sign In or Register to comment.