[LAU] DIY digital control surfaces

I seem to have gotten an itch to make some control surfaces for my home recording system. The first thing I find is that hardware is expensive and software is cheap (money wise, time is something else). Fewer pots and switches costs less and so they need to be multi-functional. This means momentary switches with coloured lights in them, rotary encoders, and motorized faders. So, how about a touch surface? 7inch android things don't cost much and have wireless and stuff... and play games when we are bored ;) with a touch surface you have to watch what you are doing all the time, real knobs and sliders let you feel. digital mixers use a mix of things... but no mouse that I have seen. Generally at least one touch screen though. It is used for all the stuff that is hard to use controls for. But also for remote control. The diy sites show the rotary encoders with light strips to show position, but I don't see this on the mixers... they give feedback through the touch screen instead. The encoder is $2, the light strip is $15. I am not sure what the interface is like, but it would seem simpler than a pot. Encoders are fine for starting from where I am and moving, but for some things a fader is still needed. If it is going to be used for more than one thing, it needs to be motorized. This doesn't seem too bad at $20 for the fader/motor combination.... but the support stuff has to be there too. It needs a motor driver, encoder and (so they say) touch sensing so the motor won't fight against your finger. There seem to be "brains" out there with switch and analog inputs with USB or midi ports. (and led outputs) Ya the stuff is all there. Some other ideas: for faders on a touch pad (screen or drawing pad or whatever) The point where the fader is right now does not matter, only that it can be moved in the right direction without jumping to whereever the finger first touches, tactile feel could be added plastic template that has slots where the faders are supposed to be. This would be cheap to try (compared to building just about anything) and I have wanted a drawing tablet to try other things anyway. For switches the keyboard has got to be the cheapest thing... only one thing is focus changes. Linux is very nice in recognizing and using new USB things. If I plug in a second keyboard, I now have two keyboards that do the same thing (mice work this way too). I want to use the second keyboard as direct input for my own program that takes key presses in and puts midi messages out to a jack port. In fact it may be an interesting tool to make a keyboard driver that uses one key to switch modes between midi mode and keyboard mode on the main keyboard even. (that strange flag key for example) Anyway, is there an easy way to grab a keyboard device before the system does? This looks to be /dev/input/event7. There is a utility called actkbd that reads this. And I guess it can run a script for any one key or just output to stdout the key press. Anyone have a better idea? -- Len Ovens www.ovenwerks.net