Hi Richard, How far have you gotten with this stuff? Should we be pulling this MIDI mapping in for the 1.6.0 beta release?
Thanks, Albert On Tue, 2007-10-23 at 18:25 +0000, Richard Morgan wrote: > Hi, > > A "first draft" for supporting the BCD3000 midi controller is available here: > > http://www.ricland.co.uk/mixxx/BCD3000.midi.xml > > I have the basic functions working (ie all faders and most buttons with > relevant functions). Unfortunately there is no midi send support in the linux > alsa midi drivers which has rather stalled the mapping of the leds. There is > also a data request midi command which can be sent to return all of the midi > cc values from the controller, this would be handy to synchronise the > onscreen controls to the positions of the hardware controls on startup. > > The spread64 controller does work for the rotary controls but gives quite > sluggish performance as it uses the 63/65 values as stop values so moving the > wheel slowly doesn't produce any result. Also the midi events generated don't > always finish with a 63/65 which leaves the pointer "creeping". In terms of > resolution a quarter turn of the wheel produces approx 24 midi events. Rather > than using a timer, as suggested previously, you could define an interval, > say 1/20 of a second, and have a formula something like > > seek = interval * (<midi cc value> - 64) > > My only problem with using a timer is that the wheel would overshoot waiting > for the end of a timer period. The interval method has the disadvantage of > introducing the steps of the interval length but hopefully we can choose an > interval which is small enough to provide fine adjustment but then with > enough acceleration to make fast scrolling possible. > > The only other small issue is that the cue_set button needs 2 presses to set > the cue point, which seems strange. > > In terms of audio outputs in linux using the generic alsa-usb module provides > one four channel output device which can be routed as two stereo outputs > (main and headphone) the latency in linux also seems to be fairly low by > default. The instruction manual confirms that four channel output in windows > is only available using the asio drivers, the wdm direct sound driver only > supports 2 channel output, ie headphone and main are cloned. The latency > using these drivers is pretty high though. I have tried using a separate 6 > channel usb soundcard but you can only choose one output device and it only > produces stereo output. I think this is a limitation of the Tracktor LE > software but I don't want to pay for the full version without guarantees. > > It is rather unfortunate as the hardware is very good and tracktor LE should > be quite competent. It seems only a small proportion of laptop computers are > affected (My laptop is the only of my 3 computers with windows installed and > the one I really wanted to use the BCD3000 with.), but the whole package is > let down in my case by the asio driver issue. The support forum on > behringer's website contains more information about which laptops are > affected and assures me that they are working on a fix for the problem. > > It's not all doom and gloom though as I now have enough working to use mixxx > and linux to get the four channel audio output from the unit. > > Now is probably not the best time to admit this but my c++ skills are > beginner at best, I wonder if anyone else is working on getting the alsa midi > output working? I am certainly willing to put some effort into getting this > working myself but it's going to take some time to get my c skills up to > scratch. I am rather throwing myself in at the deep end so any pointers on > where to start would be appreciated. > > I'll leave it there for now. > > Ric > > > > > ___________________________________________________________ > Want ideas for reducing your carbon footprint? Visit Yahoo! For Good > http://uk.promotions.yahoo.com/forgood/environment.html > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > Mixxx-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/mixxx-devel ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Mixxx-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mixxx-devel
