I touched on this with the announcement that the controls were working, but it’s now time to get an in-depth explanation of how to actually configure these. First it’s important to note that there are several options when performing this task; some people choose to use an iPac, which is a microcontroller that you simply hook the controls into. In my case because I like to save money, we took apart an old keyboard and rigged the controls into it.
First you’ll need to strip the keyboard down to actually get to the capacitive panels which connect the two circuits together. It’s essentially the process of reverse engineering the connection; you’ll see two sheets that cover each other like so:
It’s a simple mechanism by which when Q is pressed, lines 1 and 3 are connected and complete the circuit. The micro-controller attached to the keyboard understands this combinations of 1 and 3 as Q, and sends the appropriate signal to the computer. You’ll need to find the actual keys used for the Winnitron system at http://winnitron.ca/developers and locate the combinations for each key.
To assist in finding combinations, I wrote a small HTML page which monitors key presses (as you can’t easily tell which keys are which when you’ve taken all of the keys off :P). I also found it helped to note down in notepad which keys were on which circuits so that they could easily be paired up later.
Attaching the arcade controls is probably something that can only be explained with some very poorly taken pictures. In some cases, multiple keys may be on the same circuit (as shown with both Q and A being along circuit 1) and you’ll need to attach the circuit to multiple points on the arcade controls.
If you still don’t get what’s going on, the time-lapse should assist you in working out exactly how it went down (I still need to edit the video; it should be up hopefully tonight). Essentially the coloured wires shown in the picture above are replacing the circuits originally in the keyboard’s layers. The red wire for example, might be acting as circuit 1 in the diagram above (if the diagram above had any relevance to how the circuits are actually laid out underneath the keys of course :P).
Most of this step is trial and error, and logical thinking as to how best to connect all of the endpoints required along a circuit. It also requires you to know how to solder and in general, know electronics. The next step is cutting out the screen panel; although we have cut out the panel, we need to cut out the actual section in which the screen will be placed.
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