Analog Devices ADSP-21479 EZ-Board, Руководство пользователя

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S/PDIF Interface
1-20 ADSP-21479 EZ-Board Evaluation System Manual
S/PDIF Interface
The ADSP-21479 processor has a built-in S/PDIF transmitter and
receiver for digital audio applications. The EZ-Board supports the S/PDIF
interface and brings out both the transmitter and receiver via RCA
connectors
J6
and
J7
, respectively. The S/PDIF’s in and out pins are con-
nected by DAI pins via switches
SW1
and
SW7
:
• DAI pin 1 (
DAI_P1
) as
SPDIF_OUT
• DAI pin 18 (
DPI_P18
) as
SPDIF_IN
SW1
and
SW7
can be turned
OFF
to disconnect the DAI pins from the RCA
connectors if the pins are used on the expansion II interface. See “DAI [1–
8] Enable Switch (SW1)” on page 2-8 and “DAI [17–20] Enable Switch
(SW7)” on page 2-11 for more information.
Audio Interface
The AD1939 device is a high-performance, single-chip codec featuring
eight digital-to-analog converters (DACs) for audio output and four ana-
log-to-digital converters (ADCs) for audio input. This translates to four
stereo channels of audio out and two stereo channels of audio in.
The codec can input and output data at a sample rate of up to 192 kHz on
all channels.
The analog audio channels are available via single-ended RCA connectors
(
J4
and
J5
) or differential DB25 connectors (
P8
and
P9
). By default, the
EZ-Board is shipped with the RCA connectors used by the AD1939 codec
for audio in and out. To use the differential connectors, change DIP
switches
SW15–18
. A standard, off the shelf DB25 connector to XLR cables
is required to operate in this mode.