Studio Technologies 76D 2014 - Manual (Page 46)

Issue 11, May 2014 Model 76D/77 User Guide
Page 46 Studio Technologies, Inc.
for Surround
of course with no meaningful audio signal
present. As soon as a valid sync signal
is again connected to the Model 76D the
monitor outputs will automatically switch to
their correct sample rate and audio signals
will again be present.
Power Down
Great care was taken in the Model 76D’s
design to minimize the chance that clicks,
pops, or other objectionable audio signals
will be present on the monitor outputs.
A power-down circuit supplies the main
microcontroller integrated circuit with an
indication that a power loss is imminent.
When this condition is detected the monitor
outputs will switch to silence (digital audio
“black”) in preparation for a complete loss
of signal.
Power-Up Messages
Upon mains power being applied to the
Model 76D all connected Model 77 units
will go through a power-up sequence. The
sequence starts by each of the individual
LEDs lighting in a “walk-through” sequence.
Then the 4-digit display tests all its LED
segments. Finally, a set of messages pro-
vide details on the specific Model 77 and
connected Model 76D software versions:
1. Displays 77
2. Displays Model 77’s software version
3. Displays Model 77’s unit address
(A1, A2, A3, or A4)
4. Displays 76d
5. Displays Model 76D’s main software
version
6. Displays FPgA
7. Displays Model 76D’s logic device
(FPGA) software version
After a successful system power-up
sequence normal operation will then
commence.
Error Codes Err1 and Err2
Should a problem be encountered during
power up one of two error codes may show
on the Model 77’s 4-digit display. If
Err1 dis-
plays it indicates that communication is not
taking place with the Model 76D. The most
likely cause would be incorrect wiring of the
data pair linking the two units. Err2 indicates
that the Model 76D is having problems
with its internal logic device. (A high-speed
field-programmable gate array (FPGA)
serves as the digital “heart” of the Model
76D and without it no audio activity can
occur.) The only way to remedy this condi-
tion is to first try removing and reconnecting
mains power. (And that’s a long-shot as to
whether it would accomplish anything.) If
the error code continues to be displayed the
Model 76D must be returned to the factory
for service. Note that for the vast majority of
StudioComm systems neither of these error
codes, especially Err2, will ever appear.
Error Code Err3
As previously discussed in this guide, the
bass management function only supports
input signals whose sample rate is 44.1, 48,
88.2, or 96 kHz. If during normal operation
this condition is not met, it’s possible that
Err3 will display and the mute all function
will be automatically enabled. This will occur
if the bass management function is config-
ured to be enabled for either or both the sur-
round and stereo post-fader monitor outputs
and an input with a non-compatible sample
rate has been selected. In this scenario,
selecting a different input with a sample rate
of 44.1, 48, 88.2, or 96 kHz will return the
system to normal operation.