Midi; Word Clock; Word Clock Input And Output - RME Audio Fireface UFX+ User Manual

21.4 MIDI

Fireface UFX+ offers two MIDI I/O via four 5-pin DIN sockets. The MIDI ports are added to the
system by the driver. Using MIDI capable software, these ports can be accessed under the
name UFX+ MIDI Port.
All RME MADI devices support the invisible transmission of MIDI via MADI. MIDI data can be
transmitted from/to other RME devices with MADI ports, without any additional line or cabling
between computer (MADI interface) and external units. These ports can be accessed under the
name UFX+ MADI Optical and UFX+ MADI coaxial or UFX+ MIDI Port 3 and 4.
The MIDI ports support multi-client operation. A MIDI input signal can be received from several
programs at the same time. Even the MIDI output can be used by multiple programs simultane-
ously. However, due to the limited bandwidth of MIDI, this kind of application will often show
various problems.
Note: The MIDI input LEDs display any kind of MIDI activity, including MIDI Clock, MTC and
Active Sensing. The latter is sent by most keyboards every 0.3 seconds.

22. Word Clock

22.1 Word Clock Input and Output

SteadyClock guarantees an excellent performance in all clock modes. Based on the highly effi-
cient jitter suppression, the Fireface refreshes and cleans up any clock signal, and provides it
as reference clock at the BNC output (see chapter 39.8).
Input
The Fireface's word clock input is active when Clock Source in the Settings dialog has been
switched to Word, and a valid word clock signal is present. The signal at the BNC input can be
Single, Double or Quad Speed, the Fireface UFX+ automatically adapts to it. As soon as a valid
signal is detected, the WC LED is lit, and the Settings dialog shows either Lock or Sync (see
chapter 39.1).
Thanks to RME's Signal Adaptation Circuit, the word clock input still works correctly even with
heavily mis-shaped, dc-prone, too small or overshoot-prone signals. Thanks to automatic signal
centering, 300 mV (0.3V) input level is sufficient in principle. An additional hysteresis reduces
sensitivity to 1.0 V, so that over- and undershoots and high frequency disturbances don't cause
a wrong trigger.
The Fireface UFX+ word clock input can be not terminated or internally terminated (75 Ohms).
The state is comfortably selected within the Settings dialog. To terminate the input check the
option Word Clock In Term. under Input Options.
Output
The word clock output of the Fireface is constantly active, providing
the current sample frequency as word clock signal. As a result, in
Master mode the provided word clock is defined by the currently used
software. In Slave mode the provided frequency is identical to the one
present at the currently chosen clock input. When the current clock
signal fails, the Fireface UFX+ switches to Master mode and adjusts
itself to the next, best matching frequency (44.1 kHz, 48 kHz etc.).
Selecting Single Speed in the Settings dialog causes the output signal to always stay within the
range of 32 kHz to 48 kHz. So at 96 kHz and 192 kHz sample rate, the output word clock is 48
kHz.
User's Guide Fireface UFX+ © RME
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