Touch pad midi controller

Hi guys and girls. I wanted to know if you guys can help me or at least point me in the right way.

I want to turn a USB touch pad in to a a midi controller. I found a project on intrustables that more or less dose. But the person took one out of a lab top.

Im trying to figure out what I need to buy. My idea is this use two USB jacks and one midi out jack. More or less one USB as the input for the touch pad this way I can easily switch to a different one or bigger one etc. , then have a midi out and a USB out. The USB out would be used for software synths and the midi out for other syths etc. Would I need a second USB out or would the one on the board be used for this.

What arduino board would you guys say to go with. Can I use the Spark fun Arduino Serial USB Board as the input from the USB touch/track pad?

Creating a midi-port is possible with an arduino.

The standard USB port found on arduinos and most adapterboards are USB-slave ports though. When the equipment you want to connect has USB-host-capabilities and knows how to handle a com: -port, you can attach 'm. (arduino shows it self as an Com-port to a PC)

If not... it would be more or less like attaching a USB keyboard to a USB mp3 player, both are slaves. They basically only respond and one can't control the other.

Some people have however create USB-host shields you can attach to the arduino and giving it host capabilities like... a PC.

USB uses a quite difficult protocol though. When you're lucky people may perhaps... already have used an USB-host shield to attach synthesizer/touch pad, if not, you'll probably have some serious programming to do.

You can't for example just connect a USB-hub to a USB-Host shield, attach a mouse, memorystick etc and let the arduino find some drivers. You'll probably have to write them yourself and are limited to the small amount of memory of the arduino.

You may want to look for a touch pad that uses RS-232 and preferably is TTL-driven, that would save you one USB-host-port to program. I don't know your synths and also don't know what capabilities they have nowadays. (mine is really ancient/ only has midi). But... I guess most won't have USB-host capabilities.

Using a small PC sounds as the easiest solution (may still have to program a lot) if you really need the USB-solutions, but with a bit of luck the next commenter might know a way that does... make it possible easier :)

Well I think I'll just hack the track pad seems like it will make it easier for me. And save money that way lol.

I don't really need a midi cable out so forget that. So If I get this right...I can just use the USB on the board to connect to my Mac and have it show up as a midi input like I do with my keyboard. I got most of the code figured out and my buddy when he get back to town said he'll fix it lol.still learning about inputs and out puts.

Can't tell you whether the arduino will show up as a midi-device, unfortunately I only have windoze/Linux running here and haven't had the chance to play on/with a USB-enabled synth yet. Playing acoustically (drums) most of the time, I hardly did research in this part of music yet.

Should your synth now present itself as a Comport-device to your MAC, which you control as.. midi-device by music-software you probably can.

Hacking the touch pad will need work too, but may indeed make things a lot easier.

One thing I wonder, if you don't really need midi, wouldn't the MAC with free 2 USB ports plus the right program be enough ?

The more "we" know, the better the answers may get, could you give some specs of the equipment you'd like to use and a link to the instructable ?

Thought I posted that.

I was hopping I could make it a standalone synth instrument.So once I learn more i can do other stuff with it. One Idea I got from the flaming lips was put it in a rock band guitar and use the buttons to hold notes and trigger other stuff.

I build basses and do repairs, I built my own 7 string bass. I'm used to building effect pedals and been wanting to do this for some time. I kinda fell into Useing synths cause of the fact bands cane and went and want to be able to record stuff all the time. That and some times it's fun just making weird sounds.

I figure x would be pitch and not sure what y should be,attack maybe.

If you have an UNO or Mega2560 then you can reprogram the atmega8u2 with MIDI device firmware so the Arduino will appear to be a USB MIDI device when plugged into a host PC. You can get the MIDI firmware, source, sample sketch and details here:

Just find a PS2 touch pad (easy enough - the synaptics ones are probably best as lots of people have used them before and they are everywhere).
Find the absolute library for synaptics touchpads.
Connect to arduino.
Use MIDI out examples (if you want to connect it as a MIDI device) or use some software on a computer to decode stuff from the arduino (over the USB serial port) or re-program the ATmega8U2 to act as a USB device (MIDI interface).

thank for the advice ill check back in once i get the components.

i figure ill get the pad working then try to figure out how to had buttons etc from a rockband guitar.

To get the MIDI over USB functionality, that will be recognized on the PC side as a MIDI interface, buy one of these:

They are less than 8$

You just hook up your Arduino to send MIDI to its MIDI plug and connect the USB plug to the PC = instant Aduino -> MIDI ->USB

I think I'll just do what mikmo suggested.Or I mite see if I can get that midi in and out shield that spark fun sells and see if I can get that to work instead and just use a midi to USB adapter. That way I could make them for a few friends and they can save some cash if the have the midi to USB. I'm hopping I can get the track/touch pad working as a midi Instrument not as a controller ie I want it to produce midi notes not act as a daw interface to control sliders etc. Thank in advance.