Building a custom controller (some How-To's)

[ruig]

Hi, I'm a regular reader of DJtt and you got me to get into controllerism at last I'm an amateur mixer and use CDj players for mixing my tracks, but i have worked a lot with traktor 2 and 3 before I bought the CDj players.

So now I'm trying to build a small custom controller and have been reading several sites about midi, hid and controllerism and I'm quite lost..

The controller I want to build consists of deck control buttons (cue, play, pause, pitch bend...), volume faders and EQ knobs so I can control traktor.

I have some experience programming PIC microcontrollers (with C language) and that's why I didn't want to buy any Arduino or U-HID board and build something similar myself, connect the sensors that I need and send the data out ready to be interpreted by the software.

1st question:
What data format should my controller deliver to the pc? MIDI? HID?

2nd question:
I wanted to send the data for traktor via USB, is it possible??? Do i need to change the data format because of that or the USB transmission acts only as a channel where MIDI data passes through???

3rd question:
What does the controller have to do (in terms of communication) when connected to the pc so that the pc recognizes the controller as what i want it to be recognized (a MIDI controller)???

I'd apprecciate if someone could help out pointing me in some direction.
Good vibes from PT

[midifidler]

1st question:
What data format should my controller deliver to the pc? MIDI? HID?

This depends on what communications protocol you choose, ie midi, serial, usb, even Blue-tooth !

2nd question:
I wanted to send the data for traktor via USB, is it possible??? Do i need to change the data format because of that or the USB transmission acts only as a channel where MIDI data passes through???

This is possible and not to difficult if you are happy doing some coding. The form the data will take depends on what drivers you use for your project. If you create a custom driver you can have your own data structure and once the data has arrived the driver will convert to midi. This is really only useful if you have data other than midi that needs to be sent to your device, or if you want to use it with OSC as well as midi.

3rd question:
What does the controller have to do (in terms of communication) when connected to the pc so that the pc recognizes the controller as what i want it to be recognized (a MIDI controller)???

I would recommend using the AT90USB1287
http://nz.mouser.com/Search/ProductD...BQcNpICy4077ml

This family of micro-controllers has built in USB with a wide range of open source drivers supporting everything from mass storage to Midi.

This means when you plug the device in it will come up as a device in you audio software rather than having to pipe it through loopbe or a similar router.

[jean_pierre]

The CUIduino is pretty neat too, a cross between the CUI and the arduino, one of the cooler bits is that it truly supports USB (opposed to serial over) and in turn shows up as a proper HID device and can natively rap in MIDI/OSC.