From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kristian Amlie Subject: Re: How to add a new MIDI device to the usbaudio driver Date: Tue, 23 Aug 2011 13:57:14 +0200 Message-ID: <4E53959A.7090702@amlie.name> References: <4E5234F0.8000502@amlie.name> <4E52401C.8030605@amlie.name> <4E537524.9010303@ladisch.de> <4E537BE9.4050004@amlie.name> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from oproxy8-pub.bluehost.com (oproxy8-pub.bluehost.com [69.89.22.20]) by alsa0.perex.cz (Postfix) with SMTP id C8A131039D9 for ; Tue, 23 Aug 2011 13:57:48 +0200 (CEST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: Daniel Mack Cc: alsa-devel@alsa-project.org, Clemens Ladisch List-Id: alsa-devel@alsa-project.org On 08/23/11 12:16, Daniel Mack wrote: > On Tue, Aug 23, 2011 at 12:07 PM, Kristian Amlie wrote: >> On 08/23/11 11:38, Clemens Ladisch wrote: >>> Kristian Amlie wrote: >>>> idVendor 0x0403 Future Technology Devices International, Ltd >>>> idProduct 0xb8d8 >>> >>> There is a kernel driver for this chipset; try >>> "modprobe ftdi_sio product=0xb8d8". This will give you a serial port >>> which you can try to configure for the correct baud rate and see whether >>> MIDI bytes come out. (There is currently no mechanism to make a MIDI >>> device from such a serial port; this would require extending or creating >>> a driver.) >> >> Forgive me, I'm not very well acquainted with how serial drivers work in >> Linux. The driver did give me a new device, so here is what I tried: >> >> $ setserial /dev/ttyUSB0 spd_normal uart 16550A >> $ cat /dev/ttyUSB0 > dump >> >> I was not able to get any output from the serial device, however, while >> cat was running and I was pressing buttons on the instrument, it >> spontaneously changed program on me (MIDI program change), so >> *something* goes across the wire. > > Try "cu" (provided in the package "uucp" on some distributions), and > see if you can make the hardware operate on 31250 Baud, which is the > nominal rate for MIDI. If you can, you should be able to receive a raw > MIDI byte stream. But as I say, I think that requires a special > divider setup that is not supported by the ftdi_sio driver. I was not able to to use 31250 baud as you suggested. However, I tried 38400 baud, and that seemed to work. I got a small number of bytes everytime I pressed a key on the instrument. Using the following command line: $ cu -s 38400 -l /dev/ttyUSB0 | hexdump -C and pressing the same key repeatedly with the same force, I got the following output: 00000000 18 f9 ff 18 03 f8 18 f9 ff 18 01 f8 18 f9 ff 18 |................| 00000010 01 f8 18 fb ff 18 01 f8 18 fb ff 18 01 f8 18 fb |................| 00000020 ff 18 03 f8 18 f9 ff 18 01 f8 18 fb ff 18 01 f8 |................| 00000030 18 fb ff 18 01 f8 18 fb ff 18 01 f8 07 43 6f 6e |.............Con| 00000040 6e 65 63 74 65 64 2e 0a 07 43 6f 6e 6e 65 63 74 |nected...Connect| 00000050 65 64 2e 0a 0a 07 44 69 73 63 6f 6e 6e 65 63 74 |ed....Disconnect| 00000060 65 64 2e 0a |ed..| 00000064 -- Kristian