User`s guide
User's Guide HDSPe MADI FX © RME
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Examples for sending MIDI strings: 
- Set input 1 to 0 dB: B0 66 68 
- Set input 17 to maximum attenuation: B1 66 0 
- Set playback 1 to maximum: B4 66 7F 
- Set Output 16 to 0 dB: B8 75 68 
Note
: Sending MIDI strings requires to use programmer's logic for the MIDI channel, starting 
with 0 for channel 1 and ending with 15 for channel 16. 
Further functions: 
- Trim Gains On: BC 66 xx (BC = MIDI channel 13, xx = any value) 
- Trim Gains Off: BC 66 xx or select a submix 
Select submix (fader) in third row: 
- channel 1/2: BC 68/69 xx 
- channel 3/4: BC 6A/6B xx 
etc. 
28.6 Loopback Detection 
The Mackie Control protocol requires feedback of the received commands, back to the hard-
ware controller. So usually TotalMix will be set up with both a MIDI input and MIDI output. Un-
fortunately any small error in wiring and setup will cause a MIDI feedback loop here, which then 
completely blocks the computer (the CPU). 
To prevent the computer from freezing, TotalMix sends a special MIDI note every 0.5 seconds 
to its MIDI output. As soon as it detects this special note at the input, the MIDI functionality is 
disabled. After fixing the loopback, check Enable MIDI Control under Options to reactivate the 
TotalMix MIDI. 
28.7. OSC (Open Sound Control) 
Besides simple MIDI notes, the Mackie Protocol and Control Change commands, TotalMix FX 
can also be controlled by the Open Sound Control, OSC. For details on setup and usage see 
chapter 25.8.3. 
An OSC implementation chart can be downloaded from the RME website: 
http://www.rme-audio.de/download/osc_table_totalmix.zip 
RME offers a free iPad template for the iOS app TouchOSC (by Hexler, available in the Apple 
App-Store): 
http://www.rme-audio.de/download/tosc_tm_ipad_template.zip 
The RME forum hosts further information, more templates (iPhone…) and lots of useful user 
feedback. 










