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Hi all, For several months now I've been thinking about doing a DIY MIDIBox to replicate an expensive and hard to find accessory for my Roland VS2400 audio workstation - the Roland MB-24 meter bridge. The meter bridge is driven off MIDI data sent on channel 16. Roland rather conveniently published the actual MIDI spec used to drive the MB-24 in the back of one of their manuals (which I've inserted at the end of this post). The MB-24 was originally designed for use with the V7200 digital mixing platform, so there are some features and functions that don't get used when connected (some of the section light, and the 9th and 10th digit in the scene/timecode display). What is required is about 370 LEDs and 8 7-seq displays ie. around 420 digital out controls. Hardware-wise, I see myself needing: 1 core unit 2 DOUTx4 units for the meters and status lights... each board can control 256 LEDs in a 16x16 scan-switching arrangement. 2 will easily cover all the meter groups and other status lights. 1 DOUTx4 unit for the MTC/LED display output (actually only need 3/4s of it). Sound right? Software wise, I'm not really sure where to start. This would be my first foray into MIOS and assembler... I've done some PICAXE dev before, but I realise there's some serious work ahead. I suppose what I'm asking for are some ideas and examples of where to start. The other thing I'm worried about is the speed at which MIOS and the DOUT units can refresh the matrix of LEDs... ideally I'd want the LEDs to run at 15-25fps without any noticeable scanning or interlacing. Can the OS process data that fast? Would love to hear anyone's thoughts and ideas. Cheers, Ben. ROLAND VS-2400 - output spec for MB-24 Meter Bridge [tt]Transmits the level meter value of VS-2400CD according to the value of DISPLAY SECTION (MIDI ch. is fixed to 16.) Ignored when received. Status Second Third ------ ------ ----- AFH mmH llH mm = Note No. : 00H - 5BH (0 - 91) ll = Level Meter Value : 00H - 7FH (0 - 127) -------------------------------------------------------------------------- Level meter and NOTE No. -------------------------------------------------------------------------- Level Meter Analog Digital Input Track FX AUX/ Analog Digital Target Input Input Mixer Mixer Return DIR Output Output --------------------------------------------------------------------------------------------------- Note Level Level Level Level Level Level Level Level Meter Meter Meter Meter Meter Meter Meter Meter Number Channel Channel Channel Channel Channel Channel Channel Channel --------------------------------------------------------------------------------------------------- 0 Input 1 R-BUS 1 Input 1 Track 1 FxRtn 1L AUX 1 Output 1 R-BUS 1 1 Input 2 R-BUS 2 Input 2 Track 2 FxRtn 1R AUX 2 Output 2 R-BUS 2 2 Input 3 R-BUS 3 Input 3 Track 3 FxRtn 2L AUX 3 Output 3 R-BUS 3 3 Input 4 R-BUS 4 Input 4 Track 4 FxRtn 2R AUX 4 Output 4 R-BUS 4 4 Input 5 R-BUS 5 Input 5 Track 5 FxRtn 3L AUX 5 Output 5 R-BUS 5 5 Input 6 R-BUS 6 Input 6 Track 6 FxRtn 3R AUX 6 Output 6 R-BUS 6 6 Input 7 R-BUS 7 Input 7 Track 7 FxRtn 4L AUX 7 Output 7 R-BUS 7 7 Input 8 R-BUS 8 Input 8 Track 8 FxRtn 4R AUX 8 Output 8 R-BUS 8 8 - - Input 9 Track 9 - DIR 1 - - 9 - - Input 10 Track 10 - DIR 2 - - 10 - - Input 11 Track 11 - DIR 3 - - 11 - - Input 12 Track 12 - DIR 4 - - 12 - - Input 13 Track 13 - DIR 5 - - 13 - - Input 14 Track 14 - DIR 6 - - 14 - - Input 15 Track 15 - DIR 7 - - 15 - - Input 16 Track 16 - DIR 8 - - 16 - D.In L - Track 17 - - - D.Out L 17 - D.In R - Track 18 - - - D.Out R 18 - - - Track 19 - - - - 19 - - - Track 20 - - - - 20 - - - Track 21 - - - - 21 - - - Track 22 - - - - 22 - - - Track 23 - - - - 23 - - - Track 24 - - - - 24 - - - - - - - - 25 - - - - - - - - 26 - - - - - - - - 27 - - - - - - - - 28 - - - - - - - - 29 - - - - - - - - 30 - - - - - - - - 31 - - - - - - - - 32 MONITOR L MONITOR L MONITOR L MONITOR L MONITOR L MONITOR L MONITOR L MONITOR L 33 MONITOR R MONITOR R MONITOR R MONITOR R MONITOR R MONITOR R MONITOR R MONITOR R 34 MASTER L MASTER L MASTER L MASTER L MASTER L MASTER L MASTER L MASTER L 35 MASTER R MASTER R MASTER R MASTER R MASTER R MASTER R MASTER R MASTER R -------------------------------------------------------------------------- 36 37 38 39 40 Channel Status 1ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 41 Channel Status 2ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 42 Channel Status 3ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 43 Channel Status 4ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 44 Channel Status 5ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 45 Channel Status 6ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 46 Channel Status 7ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 47 Channel Status 8ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 48 Channel Status 9ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 49 Channel Status 10ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 50 Channel Status 11ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 51 Channel Status 12ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 52 Channel Status 13ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 53 Channel Status 14ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 54 Channel Status 15ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 55 Channel Status 16ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 56 Channel Status 17ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 57 Channel Status 18ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 58 Channel Status 19ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 59 Channel Status 20ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 60 Channel Status 21ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 61 Channel Status 22ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 62 Channel Status 23ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 63 Channel Status 24ch 0:Off, 1:Play, 2:Bounce/Source, 3:Rec 64 65 66 67 68 69 70 71 72 SCALE 0:X1, 1:X1/2 73 LOCATION 1:PRE FADER, 2:POST FADER 74 75 76 77 78 8SEG.MODE 0:Measure/Beat, 1:Time Code, 2:Clock+Scene 79 OVER RANGE 0:0db 80 MASTER MUTE 0:OFF, 1:ON 81 PEAK HOLD TIME 0:OFF 82 83 84 85 86 87 88 CLOCK HOUR(*1) / MEAS. MSB (*2) 89 CLOCK MIN.(*1) / MEAS. LSB (*2) 90 CLOCK SEC.(*1) / BEAT (*2) 91 SCENE (*1) / TICK (*2) 92 (*1) When 8SEG.MODE is 2. (*2) When 8SEG.MODE is 0. --------------------------------- Level Meter Value and Level --------------------------------- Value Level 0 0dB 1 -1dB 2 -2dB : 127 -Infinite [/tt]

Heheh, I understand. I think you've already done enough mate - it was actually quite astonishing looking at this whole project when I first saw it... making homespun tube guitar amps is one thing, but conceptualising, designing and building something as sophisticated as this?! I take my hat off to you. The only real aim of mentioning the arcbridge thing was to see if there was anything standing in the way of me being able to somehow implement it, sometime in the future. That meant simply not being limited either by the LogicControl protocol system (obviously something I can't change) or the basic MIDIBox/MIOS architecture (which for all intensive purposes, is working just fine as is). If it came down to creating an alternate version of the LC application, writing host helper apps or designing extra dedicated hardware modules, that's cool, I can (hopefully) do that, in time. Obviously in the spirit of the MIDIBox project, I'd want to share that with others so they can use it and hopefully improve upon it too. I guess I was also keen to see what others thought; if enough people said "hey, I like... let's do it" then perhaps it might (have) become its own little communal project. Hopefully that may happen, but first thing's first... I better build the base LC! Cheers all....

Yeah, it runs on some kind of custom audio engine, I think it is more akin to a digital mixer like the Mackie d8b et. al. The hotswapping stuff is just mad though. Very mil-spec! TK, just to clarify... the MIDI data bottleneck issue. Is that only when MIDI connections are merged or is it an overall system issue? Thinking back to how the actual LC/MC/XTs are used, don't they have to give each its own MIDI I/O pair from the host computer? The driver/protocol sees each device separately and does the "control surface integration" from the software itself. If a USB 10xMIDI I/O unit can handle most of those I/Os running at full bandwidth (which is only 31Kbit or something)....? I think this would require some sort of admendment or extra software with the LC/MC driver to shift focus onto the master (physical) LC though, as the connection between it and the XT meter/buttons would be through the host system only. Perhaps there is a way to interlink them.... oh well, perhaps I just better build a standard unit first! ;-) That's sad about the Philips faders... wow... 16xAU$40 is.. jeez! Do people do group buys on motorfaders? Is anyone interested in doing one?

Thanks for the reply Thorsten. I must have read that page several times before, I can't believe I didn't notice the Penny & Giles had already been checked :-[. My bad. From what I've found out the P&Gs are really expensive too, perhaps that's no great loss ;-) Out of the ALPs and Panasonic which are people using more? By the looks of things the Panasonic is the better fader in terms of speed, noise and pricing yet lacks the touch sensor... is that enough to pull people to the ALPs or is a separate switch fine for touch? On the expanded meter-bridge-select thing... now, please forgive me if I'm being ignorant of something, btw, the idea has been mulling in my head for a few days... on the real Logic/Mackie Control you can add XT expander units - each with 8 full channel strips. Just checking their website now, there doesn't appear to be a limitation on the number of expanders that can be used... though I've read that combined MidiBoxLC projects have a ceiling of 32 channel strips, so I'm presuming you can add 3 XTs. The 'full meter bridge' could be considered to be your LC + x number of XT units, minus all the faders, vpots, etc. bar the "SELECT" switch and level meter for each channel strip. From a MIDIBox perspective, you'd be down to a Core, a DIN4 and however many DOUT4 modules you need to drive the meters per group of 8, yeah? Obviously to get the advanced bank selecting functions to work - selecting a track/range from any "virtual XT" module and shifting the track mixer view within the actual 8-16 physical faders - would require some pretty serious rewriting of the modules of the LC application. Perhaps some extra custom hardware to help translate too. My current theory is that if the control protocol can be happily fooled (ie. the software thinks that it is just connected to an LC and a bunch of XTs), and there isn't some limitation in MIOS or the basic MidiBox system which would prevent it from working, then with the right modules and extra code, it could conceivably happen. I'm getting into more serious PIC programming and digital circuit development myself and if it is doable, then would certainly be keen to lead the way, so to speak. Anyway... that's how I saw it in my head. I'm really only just starting to learn about the Mackie/Logic Control protocol, MIOS and how MIDIBox does its thing, I'm just working on what seems logical, so certainly if I'm talking out my arse please let me know! Cheers!

Hi there everyone, I should introduce myself first. My name is Ben, I live in Tasmania, Australia... graphic designer by day, borderline hobbyist/semi-pro recording/live engineer and frustrated guitarist/vocalist/songwriter/producer by night and weekend. I stumbled across the MidiBox about a month ago and have been very excited about making a custom control surface for my Logic Pro setup; unfortunately I'm also very excited by several other DIY projects which I'm already started, so, hehe, one thing at a time ;-). I just had a simple question: has anyone tried using Penny & Giles motorfaders in the LC project? You just hear about them being a high standard in many commercial control surfaces, was just curious if anyone's given it a go... or is it still a choice between Philips and ALPS? Not so much a question, more an idea.... have a look at this: http://www.smartav.net/products.html and more importantly, this: http://www.gearwire.com/smart-av-smart-console.html The idea of having 8-16 faders but 64 or however many level meters with their own access button seems, to me, just pure genius! Okay, there is a question then... could such a thing be implemented into an LC? I'm guessing it would fall outside of what is achieved through the Logic/Mackie Control protocol... perhaps a MIDI to keyboard converter or some kind of small helper app? Just throwing ideas into the ocean... thought it was cool ;-) Cheers...