Joan a 21:30, 16 oct 2011

2011-10-16T21:30:02Z

Pàgina nova

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He enviat un mail a la LAD. Vull que si tinc un projecte fet amb arduino, per ex un controlador MIDI, sigui USB-compliant i que m'aparegui a la llista d'aconnect.
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I think its more a task of "make arduino behave as a standard-compliant usb-
midi device".

If you have that code, please share it :-)

Have fun,

Arnold
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Not possible with the old Arduinos (FTDI chip), but super easy with the
new generation, the Arduino Uno: http://arduino.cc/en/Main/ArduinoBoardUno

Flo
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Thanks for make me remember ttymidi. I tried it and is perfect for the purpose to connect arduino to fluidsynth.

Returning to the problem..., I imagine something like plugging arduino and appearing automatically in aconnect. Maybe the solution is to hack the FTDI driver. FTDI is the chipset that converts serial to USB, and needs an FTDI driver to create a virtual COM port: /dev/ttyUSB0. The solution could be hacking the FTDI driver with the ALSA libraries driver and making it an ALSA sequencer port.

Joan Q
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In theory you could reprogram the FTDI chip to appear to be a
class-compliant MIDI device. Since a MIDI port is just a serial port
with a funny baud rate and a current-loop interface, it shouldn't be
hard - you don't care about the physical interface and the software
interface just throws bytes down a serial port.

You could use ttymidi to receive data from the arduino, but not send
MIDI to it. Of course, you could launch ttymidi from a udev script so
that when you plug in the arduino it fires up and lets the port appear.

Gordon MM0YEQ
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Aquí està l'aportació més interessant:
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Hi,

I've done that with the V-USB lib from obdev.at:

"V-USB is a software-only implementation of a low-speed USB device for
Atmel�s <http://www.atmel.com/> AVR� microcontrollers, making it
possible to build USB hardware with almost any AVR� microcontroller, not
requiring any additional chip.V-USB can be licensed freely under the GNU
General Public License or alternatively under a commercial license."

http://www.obdev.at/products/vusb/index.htm

The project discussion:
http://forums.obdev.at/viewtopic.php?f=8&t=1352

Project page, schematics and software download:
http://cryptomys.de/horo/V-USB-MIDI

Ciao, Martin
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Very interesting website (note 'l' is missing from the 1st url). I wonder if
it would be possible to use some variant of this as a replacement for things
like the Midisport series of converters. Maybe use an arduino and translate the
serial pins as 'real' MIDI then hooked up to the USB software. Would be quite
convenient to not have to have a firmware downloader etc.

--
Will J Godfrey
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Aquí hi ha el codi i l'esquema (simple) de com connectar un xip AVR directament al USB, i el software per tal que l'ordinador el reconegui (el driver). Llest per compilar i per estudiar.
*http://cryptomys.de/horo/V-USB-MIDI/
*http://www.obdev.at/products/vusb/index.html

Arduino i driver USB - Historial de revisió

Joan a 21:30, 16 oct 2011