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Digineural

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  1. Digineural
    In general I don't recommend starting any project with an enclosure that is smaller than what you can fit a proto version of your project in. But my enclosure supply just about gone, so I'll use what I have. The tekbox from TEKO enclosures. (NOTE: If for some insane reason you decide to emulate this work in progress, buy a tekmar case. It's the same but bigger)




    Stage 1: Planning (barely) ahead.

    Since this isn't a masterpiece by the MB gods, I 'm just going to build the control surface on veroboard (protoboard) and hand wire each component. This gives me that added option of making components sit really close to each other without worrying about PCB traces. My veroboards are from RadioShack. They are pretty standard 0.05" spaced holes and have pads on one side. To make sure the control surface would actually fit in the tekox, I created a new part of the pads in Eagle and then placed each component on the grid. My LCD in this picture is from the SparkFun eagle library. I also placed an optional 4 digit 7 segment display and knobs on the layout. (If you can, always place the knobs on encoder layouts. Even if its just a circle. I have at least 3 old projects that I never use because there isn't enough space for knobs and it looks like crap)



    For all intensive purposes the 4 digit 7 segment display will probably not get populated (but its nice to have the option to put one there).

    Stage 2: Sizing up the competition

    As you can see in the picture below, the 1:1 print layout of the control surface fits perfectly in the recess of the top half of the enclosure. The knobs might protrude on either side of the case recess, but I'll just have to live with that.



    Still not done checking though. I've burned myself enough to know that I'll have to test fit some parts on hand to make sure this is all going to work. After testing the LCD, I realized the SparkFun 16x2 LCD pin out is off by 0.05" but the outside dimension is perfect The SparkFun display was perfect. The Displaytech LCD footprint I used wasn't. I'll adjust the part and retest the fit. In the next version, I've also rotated the swing pot 180 degrees so that I can add the record indicator led next to the shift indicator led.

    Stage 3: 3D Rendering

    This step wasn't even remotely necessary. I'm just playing in sketchup with 3D rendering of eagle layouts. I've modified the EagleUp script and created some new models to generate a 3D rendering of this control surface. I originally had every intention of checking this against the enclosure DXF but OKW (TEKO) didn't have one available, so this is what you get. Still makes me happy to look at it.




    This project is still very much a work in progress. At the time of this writing, I'm still planning the base PCB. If for any reason the MidiBox gods see a train wreck coming, let me know.
  2. Digineural
    I've been a huge fan of the MB808 project however, I'm broke in the "I'm married", "whats mine is her's" sort of way :D. As such, my projects are typically small, hacked and require parts I had on hand from before I got married. With the exception of my MB6582. So here I am embarking on my 808 with just overstock and samples.

    The original MB-808 is far more project than I had in mind. I have a drum machine with all the kits I want, I just need to trigger it. I also want something small and portable to carry around at work while I'm waiting for things to happen. That's where this project begins.

    Planning the input section

    I usually start my MIDIBox projects with an idea of what I need to input and output. Using the schematics and some digging in code, I created a DIN map of all my switches and encoders, their original position on the DIN chain, shift register and pin number.

    I then modified the DIN map to create the most optimal layout in terms of shift register count. This list might not be perfect but it's my best guess. Below is a table of my DIN map. This will drive the creation of the base board and connections.

    808 hardware config.pdf

    Opening the kimono

    In the spirit of open source I will be sharing everything except the base schematics. This includes the libraries I created to match the PDFs TK has created. I actually like his layouts better for most schematics with some minor exceptions. I used these to help plan the layout of the protoboards and the base including encoder distances based on the knob sizes.

    This is not my complete Midibox library. I have more parts but its embarrassingly unorganized so here are my most used parts in a library. Among my favorites, are the 40x2 LCD display with the characters to guide placement and the "Waldorf" knobs (which I'm surprised nobody created). I also threw in a Lumex 4 digit 7 segment display (not verified, but close enough).


    MB.zip
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