D21m System
6-10 D21m Modules Date printed: 30.08.07
6.3 Digital I/O Cards
6.3.1 AES/EBU I/O Cards 1.949.422, 1.949.423, 1.949.424
AES/EBU input/output card with 16 Ch I/O.
With input SFCs only.
Selectable output sampling frequencies:
96 kHz, 48 kHz, 44.1 kHz, or external reference (22...108 kHz). Input SFCs
can be bypassed individually.
Output dither is selectable for every AES/EBU output from 24 bit, 20 bit,
18 bit or 16 bit. Settings are made with jumpers. Inputs and outputs on stan-
dard 25-pin D-type connectors (female).
SFC Delay: Enabled input and output SFCs each cause a delay (D) that depends on the
SFC’s input and output sampling frequency (f
S_IN
and f
S_OUT
). Input and output
delays can be calculated using the formulas below.
[2] f
S_OUT
> f
S_IN
: D =
48
f
S_IN
[s]
[1] f
S_IN
> f
S_OUT
: D =
16
f
S_IN
+ [s]
32
f
S_OUT
Examples:
• For a 96 kHz input signal and a 48 kHz system clock (i.e., the “output signal”
of the input SFC), the input delay is 40 output samples or 0.833 ms (formula
“1”).
• For a 48 kHz system clock (i.e., the “input signal” of the output SFC) and a
96 kHz output signal, the output delay is 96 output samples or 1 ms (formula
“2”).
Note: If the core is operating with a 44.1 or 88.2 kHz system clock, the output sam-
pling frequency will be 44.1 or 88.2 kHz, regardless of the jumper selection
– unless the external sync input is used and Ext. is selected; then, the output
sampling frequency corresponds to the one of the external sync signal.
Backplane Connector
Clock Selector 1 *
96 k, 48 k, 44.1 k, ext.
* for 1.949.424.xx only ** for 1.949.423.xx and 1.949.424.xx only
Clock Selector 2 *
96 k, 48 k, 44.1 k, ext.
AES Tx
AES Tx
AES Tx
AES Tx
AES Tx
AES Tx
AES Tx
AES Rx *
AES Tx
AES Rx
AES Rx
AES Rx
AES Rx
AES Rx
AES Rx
AES Rx
AES Rx
AES Out 1
AES Out 2
AES Out 3
AES Out 4
AES Out 6
AES Sync In *
AES Out 8
AES Out 7
AES Out 5
AES In 1
AES In 6
AES In 3
AES In 5
AES In 4
AES In 2
AES In 7
AES In 8
SFC *
SFC **
SFC *
SFC *
SFC *
SFC *
SFC *
SFC *
SFC *
SFC **
SFC **
SFC **
SFC **
SFC **
SFC **
SFC **
Note: Output SFCs are not tted on the Vi4/6.
