Crystal Vision Indigo ADCA412 User manual

ADCA412
Analogue to digital audio converter
Crystal Vision Ltd., Lion Technology Park, Station Road East, Whittlesford, Cambridge, CB22 4WL, England.
Tel: [phone] Fax: [phone] [e-mail] www.crystalvision.tv

Crystal Vision Introduction
Contents
1Introduction 3
System overview 4
Control 4
2Statesman 5
2.1 Statesman operation 5
2.2 Using ADCA412 controls 6
Selecting the sample rate mode 6
Selecting the reference 7
Channel swapping, single channel mode and phase inversion 7
Selecting silence options 7
Adjusting the AES output phase 8
Audio monitoring 8
Setting channel gain and input termination 8
3Using the front control panel 9
The ADCA412 menu structure 12
Setting channel gain and input termination 13
Status menus 14
Switch status menus 15
GPI sub-menu 16
Control menus 17
Option menus 18
Set phase adjustment 18
4Using card edge controls 19
Selecting the output clock source 19
Selecting the sample rate mode 19
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Channel swapping, single channel mode and phase inversion 20
Setting channel gain and input termination 20
Selecting silence warning options 20
Setting the silence threshold 21
Audio Monitoring 21
5Installation 22
5.1 Rear module connections 24
RM03 24
RM11 25
RM13 27
RM14 28
RM21 29
RM35 30
5.2 Signal earthing 31
5.3 Using GPIs 31
GPI input assignments 31
GPI output assignments (alarms) 31
GPI Connections 32
5.4 Wiring XLR breakout leads 33
5.5 Fitting a digital audio output sub-module 34
5.6 Hardware configuration 35
Setting reference options 35
Setting input analogue gain 36
6Problem solving 37
7Specification 39
Revision 1 RM13 connection table corrected, page 27. 19/06/2011
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Crystal Vision Introduction
1 Introduction
The ADCA412 is a dual analogue to digital audio converter designed to convert two dual
channel analogue audio inputs to two AES/EBU audio outputs. The module accepts either
525 or 625 references from analogue composite video, word clock or an AES reference.
There are two operational modes ‘Auto’ that allows flexible phase locked loop sample
rate control to accept a wide reference input frequency range and ‘Xtal’ that allows for
crystal locked operation at 48kHz.
In addition to analogue to digital conversion, the ADCA412 incorporates a number of
powerful features. For example, a channel swap function allows channels 1 and 2 to be
transposed, whilst the phase of the right hand channel can be inverted to correct phasing
errors. Analogue monitoring can be used to listen to each incoming stereo pair.
Also ‘near silence’ detectors monitor the audio signal level in both channels in case they
fall below –50dBFS for more than a selected period of time. Silence warning and loss of
reference warning status are normally routed by default to the GPI port for each channel.
The main features are as follows:
•20/24 bit dual analogue to digital audio converter
•+12dBu to +28dBu input level for 0dBFS digital output with input level pre-sets
for +18dBu and +24dBu
•110 Ohm balanced and 75 Ohm unbalanced output versions via sub-module
option
•choice of rear connectors to accommodate I/O format options
•external reference accepts video, word clock or AES source
•clock regeneration for 48kHz even when locked to video
•automatic 525/625 operation with AES phase adjustment in 625
•wide ranging ‘Auto’ mode for sample rates between 30kHz and 50kHz when
using AES reference outside 48kHz +/- 50 ppm
•precision, re-clocking ‘Xtal’ mode for 48kHz output sample rate when locked to
any 48kHz reference
•channel swap and RH channel invert
•loss of reference input and sustained silence warning via indicators and external
alarms
•GPIs for ‘Xtal’ and ‘Auto’ mode change, channel swap and loss of input/silence
warning
•control and status monitoring via board edge, frame/remote control panel and
Statesman
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Crystal Vision Introduction
System overview
The converter is configured as two independent converter channels each with their own
silence detection circuitry but sharing the same reference generation circuitry. Intelligent
audio routing provides for channel swapping, single channel mode and phase inversion.
A high stability ‘Xtal’ lock mode supports high quality crystal locked output sample rates
at 48kHz and a more flexible ‘Auto’ mode uses a phase locked loop for other output
sample rates. The ‘Auto’ mode phase lock loop range is useful when using an AES
reference outside 48kHz +/- 50ppm but within a wide range from below 30kHz to above
50kHz.
Two AES outputs are available for each channel from the 24 bit analogue to digital
converters. Headphone monitoring is provided for the analogue inputs.
Six different rear modules (RM) may be used with ADCA412, the RM03, RM11, RM13,
RM14, RM21 and RM35. Further details of the rear modules can be found in the
Installation chapter.
Control
Control of the card is on a first come first served basis from the card edge, Statesman, the
frame control panel (if fitted) or a remote control panel. For example, if a card edge lever
is moved the unit will switch to and remain in the ‘Local Control Mode’. If any control
panel menu is used, then the unit will switch to and remain in the ‘Remote Control
Mode’. The settings made will be remembered after a power down and the last control
mode used will be retained.
The auto-configuration process performed when an ADCA412 is first powered up, detects
the current configuration settings and restores the appropriate control.
Once this initialisation procedure is complete, the card can be controlled or configured
from Statesman, the card edge, the frame’s local control panel or from a remote control
panel.
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2 Statesman
The Crystal Vision Statesman PC control software is designed to control a range of
Crystal Vision modules via serial control from a PC.
The main Statesman application communicates with each module in a frame through an
active control panel with an LCD display or a Statesman only panel without an LCD.
Statesman will not be able to detect modules used in a frame with only a passive front
panel.
2.1 Statesman operation
Once Statesman is configured it should automatically detect any statesman compatible
modules in the connected frame or frames and display them in the main application left
hand Explorer-style window.
Open any frame by clicking on the ‘+’ sign or by double clicking on a frame. Installed
modules should be shown with module icons. Frame and module icons can be named as
desired by right-clicking or using the edit menu and choosing rename.
To aid user recognition of module and frame status quickly, the following colour and size
coding is used:
•A module is shown present by full colour and absent by greyed colour
•A module is shown open by large icon size and closed by small icon
•A module is the source of an active alarm if red and not alarmed if green
Double-clicking on a module will enable the display of the main application menus.
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Statesman main application window
The two large control panes shown in the upper and lower halves of the window may
display different menus for the same card, or controls for different cards. Click on the
horizontal button-bar between the two panes to close the lower plane or drag the button to
vary the size of the panes.
Note: For further details of Statesman configuration and operation please refer to the Statesman
manual.
2.2 Using ADCA412 controls
The configuration controls are as follows:
•Mode –48K or Auto
•Reference –AES, Wordclock, Video or Internal
•Silence time – 1.5 to 120 seconds
•Phase inversion
•Audio channel assignment
•LP filter
•Test tone/left ident
•AES output phase
•Status – reference presence, input sample rate, silence detect, GPI state
Configuration
Selecting the sample rate mode
The ADCA412 channel operates in two main modes 48K and Auto. Make the selection
with the mouse by placing a selection dot against the required mode.
The primary mode is for the output sample rate clock to be locked to the reference using a
48kHz crystal oscillator to achieve optimum distortion figures. This is referred to as
‘Xtal’ mode and should be used at all times if possible.
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The second mode uses built-in phase locked loops and VCOs to accept an AES reference
which may vary from below 30 kHz to above 50 kHz. This is referred to as ‘Auto’ mode,
and should be used when the AES reference sample rate is outside 48 kHz +/- 50 PPM.
Notes: ‘Auto’ mode can only be used with an AES reference. The ‘Xtal’ mode is designed for use
with a video, word clock or AES reference at 48kHz.
GPI connections to the Auto/ Xtal mode change line will override the card edge switch if
asserted to a logic low or grounded.
Selecting the reference
The ADCA412 output clock may be locked to AES reference, word clock, analogue video
(or black and burst) or left to run off a 48kHz internal clock. References that are available
will be shown with a green indicator.
Make the required reference selection with the mouse by placing a selection dot against
an available clock source.
Note: If a reference source is selected that is not there or is lost, the module will automatically
attempt to select one that is present. If no external reference can be found the internal clock
will be selected.
Channel swapping, single channel mode and phase inversion
Channel routing logic following the silence detection circuits allows the incoming
analogue signals to be assigned to digital outputs in a variety of ways.
The possible variations are as follows:
•channels may be swapped so that Input 1 feeds AES Output 2 and Input 2 feeds AES
Output 1
•both output stages may be assigned to either Input 1 or Input 2 effectively doubling
the duplicate outputs for a single analogue input.
•the phase of the right output of AES Output 1 OR AES Output 2 may be inverted
Make the selection with the mouse by placing a selection dot against the required options.
Note: GPI connections to the shuffling mode lines will override card edge switches if asserted to a
logic low or grounded.
Selecting silence options
Each input channel is equipped with ‘near silence’ detectors. If the audio signal levels are
sustained at below –50dBFS for more than a selected period of time, an indicator for each
channel comes on and an appropriate GPI output can be asserted low.
To change the time required for a sustained silence to raise alarms and display warnings
click on the Silence Time drop down box and select from the following range:
1.5 seconds
8 seconds
every 8 seconds until…
120 seconds
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Card-edge switches may be used to prevent silence detection from raising alarms via
these GPI outputs. Please refer to the Using card edge controls chapter for more
information.
Note:
The routing of ‘Loss of Reference Input’ warning to the GPI port cannot be disabled.
Adjusting the AES output phase
The time/phase relationship between the current reference input and the actual AES
output can be adjusted using the rotary AES o/p phase control.
Note:
The Set Phase function does not work unless a valid external reference is selected. If the
internal crystal oscillator is used, the phase control will be disabled.
To return the phase control to zero quickly, hold the mouse over the control, right click
and then select 'Calibrate'.
The phase angle setting is stored in non-volatile memory. Each reference input (AES,
Video or Word Clock) have their own memories for these values.
Every time the unit is powered up or the reference input selected or used is changed, the
new values are loaded into the ADCA output PCB to ensure optimum performance.
Audio monitoring
Audio monitoring is provided at the card edge with two miniature stereo jack sockets. The
left hand socket is connected to the Stereo 1 input signal and the right hand socket is
connected to the Stereo 2 input signal.
Setting channel gain and input termination
Please refer to the Hardware configuration section of the Installation chapter for channel
gain and input termination settings.
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Crystal Vision Using the front control panel
3 Using the front control panel
This operational guide assumes that the panel has been set up according to the Panel setup
procedure described in the Crystal Vision Control Panels manual.
Note:
It is ESSENTIAL that the Panel setup procedure is followed and any old or unknown
passwords cleared prior to using the panel for the first time.
At power up, the two line 20-character screen will display ‘Crystal Vision’ followed by
the firmware version number for the control panel. All eight control panel key LEDs will
illuminate.
The Crystal Vision control panel start up display
'Control Panel' then briefly replaces the version number display.
If the control panel firmware has been updated for Statesman control (version 1.5.0 or
higher), Statesman Mode will be entered and the message, ‘Press CAL to Exit’ will be
displayed and the CAL LED will light.
Statesman mode is entered by default
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To continue with control panel operation or configuration, press the ‘CAL’ key once. A
second press of the ‘CAL’ key will return to Statesman control.
The control panel will display the name of the card that first responds to the polling
request together with its location number.
The location number consists of the frame number plus the card position in the frame.
Selecting the ADCA412
To select a particular card in a frame, press the DEVICE key to go to the Device menu.
The top line of the display will show ‘Available Cards X’, where X is the number of cards
that have responded so far to the polling request.
The Available Cards menu
Rotate the shaft encoder and the bottom row will display the successfully polled cards by
name and location or slot number.
In the example above, the card displayed is located in the first frame in slot number 1.
When the desired card is selected press the ENTER key to access that card’s HOME
menu.
If remote control has been enabled, the control panel will then enter card mode and
communicate with the selected module at the node number last displayed in the available
cards list.
The ADCA412 Home menu
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Navigating the display
The functions assigned to control panel keys are dependent on the card selected for
control, and the panel mode. The following list illustrates the functions when controlling
the ADCA412:
DEVICE – enters Device menu to select a card or card to control / enter Panel setup when held down
during power up / shows frame status when pressed from Statesman mode
CAL – Enter or leave Statesman mode / enter Panel Diagnostics mode when held down during power
up / updates the display
Asterisk – enters Board Rename menu from the Device menu
F1 to F4 – soft keys, function assigned within each menu
HOME – moves the display to the Home menu
ENTER – accept current selection
Upward arrow – used to move up the menu structure / enter Lock Panel menu from the Device menu
Rotary control – shaft encoder used to select options or variable data
Note:
Please refer to the Crystal Vision Control Panel manual for details of the Panel Setup,
Lock Panel and Diagnostic menus.
Updating the display
The values displayed on an active front panel are only updated when an adjustment is
made and when changing menu level. If mode changes occur through the use of
Statesman, card edge controls or through automatic response to the input video signal, the
text displayed on the active front panel will not be updated immediately. If necessary,
press CAL to update the display.
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The ADCA412 menu structure
The main top-level menus are obtained by pressing the F1, F2, F3 and F4 keys from the
Home menu. Menu keys are illuminated when active and when further menus are
available. The four top-level menus are:
STAT (Status) – press F1
SWCH (Switch) – press F2
CNTL (Control) – press F3
OPTN (Option) – press F4
The following chart shows the majority of the available menus. The actual menus
available may vary slightly as ADCA412 software is updated.
The ADCA412 menu tree
Note:
Function keys and shaft encoder LEDs are illuminated when active.
Function keys associated with the shaft encoder for changing assigned values are shown
with a black circle.
The use of STATUS or SWITCH monitoring functions in no way affects whether the
module is operating in ‘LOCAL CONTROL MODE’, or ‘REMOTE CONTROL
MODE’.
The STATUS display data may differ from the actual settings due to Statesman, GPI
inputs or remote CONTROL settings from the front panel overriding the front PCB
control settings. Press the CAL button to update the display.
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Menu numbering scheme
This manual uses a simple menu numbering convention based on the sequence of keys
required to reach each menu from the top level Home menu. For example, menu 1.1.2 is
reached from the Home menu by pressing F1, then F2. Menu 1.1.2.1 is reached by
pressing F1, F2 and then F1 again.
Shorthand codes
The following shorthand codes are used in the control panel menus:
Menu code Function description
AES1/2 AES/EBU digital audio signal 1/2
ST1/2 Analogue stereo 1 or 2 input signal
GPI General Purpose Interface INPUT
GPO General Purpose Interface OUTPUT
/ Indicates no-effect when used in front of menu code
/Rph NO phase inversion of right hand channel
Rph Right hand channel IS phase inverted
AUTO Follows ref input clock frequency between 30 and 50kHz
48K Locked to 48kHz crystal oscillator
DUAL Dual channel operation
SWAP Inputs are swapped
/SWAP Inputs are NOT swapped
SNGL Single channel mode
delay Time period required for signal to remain below threshold before input silent is
asserted
s Audio signal silent (below –50dBs FS longer than delay period)
Note:
Remember, the ‘/’ symbol negates the effect of a menu code it precedes.
Setting channel gain and input termination
Please refer to the Hardware configuration section of the Installation chapter for channel
gain and input termination settings.
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Status menus
Pressing F1 from the home menu will bring up the top Status menu. The Status menus
provide the following information:
Audio activity
Audio silence sustain delay
Output sample rate
Status menu Description
The top menu line displays the currently selected
sustained silence delay before the ‘Silence’ LEDs are
illuminated, and (optionally) the relevant GPI outputs
are asserted low.
Active audio channels are indicated by the numbers
1234 (ST1Left = 1, ST1Right = 2, ST2Left = 1,
ST2Right = 2). Any silent channels are indicated by
the symbol ‘s’.
The bottom line shows the reference source in use
(REF followed by VIDEO, AES or W.CLOCK). Aref
instead of REF indicates that the source in use is an
alternative because the selected source is not suitable
or not available.
RATE shows the sample rate and AES output rate.
Note:
Each input channel is equipped with ‘near silence’ detectors. If the audio signal levels
are sustained at below –50dBFS for more than a selected period of time, an indicator for
each channel comes on and an appropriate GPI output can be asserted low.
Stereo 1 silent in audio channel 1 or 2 will illuminate ‘silent’ LED 1 and assert GPO5
low if enabled.
Stereo 2 silent in audio channel 3 or 4 will illuminate ‘silent’ LED 2 and assert GPO6
low if enabled.
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Switch status menus
Pressing F2 from the Home menu will bring up the top Switch status menu. This menu
provides the following information:
Further AES channel status
Mode selected status
GPI status
Switch status menu Description
The ‘SWTCH’ menu displays the PCB front control
SWITCH settings. F1, F2, F3 and F4 select further
menus.
The REF sub-menu shows the crystal fitted (normally 48
kHz) and the reference selected with SW3-1 and SW3-2
(AES, WORD CLOCK, VIDEO SYNCS or
INTERNAL).
The AUDIO sub-menu shows the main operational
mode (SINGLE, DUAL) as selected by SW3-6. The top
line also shows if the channel inputs are swapped in
using SW3-5.
The bottom line shows the effect of SW3-7 and SW3-8
on the phase of the RHS of Stereo 1 and 2.
The GPO sub-menu shows the effect of SW3-4 on
silence warning via GPO5 and GPO6.
The GPI sub-menu shows the state of the four GPI
inputs as explained in the table below.
Note:
The effect of swapping inputs with SW3-5 is shown differently depending on the
selected operating mode. In DUAL mode SWAP or /SWAP is shown. In SINGLE mode
ST1 or ST2 is shown to indicate which stereo input feeds both AES outputs.
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GPI sub-menu
This menu can display the following GPI information:
Display Meaning Notes
GPI1=DUAL GPI1 is NOT asserted low DUAL mode
GPI1=SINGLE GPI1 is asserted low SINGLE mode
GPI2=/SWAP GPI2 is NOT asserted low and GPI1 is NOT asserted low DUAL mode
Inputs NOT swapped
GPI2=SWAP GPI2 is asserted low and GPI1 is NOT asserted low DUAL mode
Inputs swapped
GPI2=AES1 If GPI1 is already asserted low, then GPI2=S1 means
GPI2 is NOT asserted low
SINGLE mode
Input 1 feeds AES1&2
GPI2=AES2 If GPI1 is already asserted low, then GPI2=S2 means
GPI2 is asserted low
SINGLE mode
Input 2 feeds AES1&2
GPI3=48K GPI3 is NOT asserted low ‘Xtal’ mode
GPI3=AUTO GPI3 is asserted low (only effective if AES reference
input has been selected and a valid input is present AND
GPI4 is NOT asserted low)
‘AUTO’ mode
GPI4=AES/W.CLK GPI4 is NOT asserted low AES or WORD CLOCK
reference selected
GPI4=VIDEO GPI4 is asserted low, or VIDEO syncs already selected VIDEO reference selected
GPI4=INTERNAL GPI4 ignored ADCA412 is fixed in free
run mode
Card edge switches may be used to prevent silence detection from raising alarms via these
GPI outputs. Please refer to the Using card edge controls chapter for more information.
Note:
The routing of ‘Loss of Reference Input’ warning to the GPI port cannot be disabled.
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Control menus
Pressing F3 from the Home menu will bring up the top Control menu. This function
allows the module to be configured without the need to access the PCB switches. The
menu provides the following functions:
AUTO/Xtal lock
Right hand channel phase
Single or Dual mode selection
Silence threshold delay
Re-establish LOCAL control
Control menu Description
The CNTRL menu allows remote access to the
functions normally controlled by front PCB
controls.
The REF menu allows the reference to be selected
using F1-F4 from, AES, WORD CLOCK, VIDEO
or the INTERNAL oscillator.
The MODE menu selects between AUTO and
48KHz (Xtal) modes using F1and F2.
Silence delay may be increased using the F3 ‘+’ or
decreased using F4 ‘-‘ between 1.5s and 120s in 8s
steps. In SNGL mode use F2 to select the AES
channel before changing the delay.
The AUDIO menu provides control over the main
operating mode with F1 (DUAL/SINGLE) and
provides control of the channel swap function with
F2. F3 and F4 allow the RHS of each channel to be
inverted.
Note:
If mains power is removed and re-applied the module will return to exactly the same
settings on power-up as existed when mains power was lost.
Accessing any remote Control menu will always establish REMOTE CONTROL MODE. If any
PCB switch levers or the rotary hex switch is altered, the module will switch back to ‘LOCAL
CONTROL MODE’, and operate in accordance with the front of PCB switch settings. It will
remain that way until any remote control command is received. The LOCAL button in the top
CNTRL menu, F4, will also return the unit to local control.
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Option menus
Pressing F4 from the Home menu will bring up the top Option menu. This menu provides
the following functions:
Select Stereo or Dual Channel AES message format
Adjust AES output phase (external reference must be selected)
Set test tone options
Shows sub-PCBs fitted
Option menu Description
Adjust the phase relationship between the selected
external reference and the AES output by pressing
F1 (SET) and rotating the shaft encoder. Use F2
(ZERO) followed by CAL to calibrate to ‘0.0’.
The OPs menu shows the type of output sub-PCB
fitted which can be 75R or 110R.
Use the ‘Other’ menu to access the following:
Press F1 to set the AES message format between
Stereo or Dual Channel.
Press F2 to set the Test Tone output On or Off.
Press F3 to select an Ident tone on the left hand
channel when the test tone is On.
Press F4 to select between Normal and N Cut.
N Cut puts a low pass filter in each input to reduce
the effects of noise.
Note:
The Set Phase function does not work unless a valid external reference is selected. If the
internal crystal oscillator is used, the phase control will be disabled.
Set phase adjustment
If the Set Phase function is enabled, the time/phase relationship between the current
reference input and the actual AES output will be shown to the nearest 1.5 degrees,
relative to the last calibration.
Press the SET button to enable adjustment of the AES output time/phase using the shaft
encoder. Once the desired phase has been set, press ZERO followed by [CAL] to calibrate
the display to ‘0.0’. The phase angle setting and the display calibration value are both
stored in non-volatile memories. Each reference input (AES, Video or Word Clock) have
their own separate memories for these values.
Every time the unit is powered up or the selected or used reference input is changed, the
new values are loaded into the ADCA output PCB to ensure optimum performance.
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4 Using card edge controls
The front edge of the card provides power rail monitoring, an eight-way configuration
switch bank, analogue audio monitoring outputs and a rotary control to set the silence
threshold.
LED indicators are provided to monitor power rails, input present, input sample rate and
local/remote mode.
Selecting the output clock source
The ADCA412 output clock may be locked to AES reference, word clock, analogue video
(or black and burst) or left to run off a 48kHz internal clock.
The choice is made using SW3-1 and SW3-2 as follows:
Lever 1 Lever 2 Function
UP UP AES reference selected
UP DOWN Video reference selected
DOWN UP Word clock selected
DOWN DOWN Internal clock source selected
Selecting the sample rate mode
The ADCA412 channel operates in two main modes. The primary mode is for the output
sample rate clock to be locked to the reference using a 48kHz crystal oscillator to achieve
optimum distortion figures. This is referred to as ‘Xtal’ mode and should be used at all
times if possible.
The second mode uses built-in phase locked loops and VCOs to accept an AES reference
which may vary from below 30 kHz to above 50 kHz. This is referred to as ‘Auto’ mode,
and should be used when the AES reference sample rate is outside 48 kHz +/- 50 PPM.
Note: ‘Auto’ mode can only be used with an AES reference. The ‘Xtal’ mode is designed for use
with a video, word clock or AES reference at 48kHz.
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