
Operating Modes
14-16
ADSP-214xx SHARC Processor Hardware Reference
• SRU is the input source. If the input clock and trigger signal are
synchronous, the delay is exactly 3 input clock periods. If asyn-
chronous, it varies between 2.5 to 3.5 input clock periods
depending on the phase difference between the input clock and
trigger signal.
Audio System Example
shows an example of the internal interconnections between
the SPDIF receiver, ASRC, and the PCGs. The interconnections are made
by programming the signal routing unit.
It shows how to set up two precision clock generators using the S/PDIF
receiver and an asynchronous sample rate converter (ASRC) to interface to
an external audio DAC. The PCG is configured to provide a fixed
ASRC/DAC output sample rate of 65.098 kHz. The input to the S/PDIF
receiver is typically 44.1 kHz if supplied by a CD player, but can also be
from other source at any nominal sample rate from about 22 kHz to 192
kHz.
Similarly, the phase shift for frame syncs B, C, and D is specified in the
corresponding
PCG_CTLxO
and
PCG_CTLx1
registers.
Three synchronous clocks are required in audio systems
1. Frame sync (
FS
)
2. Serial bit clock (64 x FS)
3. Master DAC clock (256 x FS)
Since each PCG has only two outputs, this example requires two PCGs.
Furthermore, because the digital audio interface requires a fixed-phase
relation between
SCLK
and
FS
, these two outputs should come from one
PCG (PCG A) while the master clock comes from the 2nd (PCG B).
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Summary of Contents for SHARC ADSP-214 Series
Page 60: ...Contents lx ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 72: ...Notation Conventions lxxii ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 130: ...Programming Model 2 52 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 264: ...Programming Models 3 134 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 290: ...Programming Model 4 26 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 296: ...Programming Model 5 6 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 396: ...Effect Latency 7 28 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 520: ...Programming Model 10 62 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 616: ...Debug Features 14 22 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 656: ...Programming Model 15 40 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 714: ...Programming Model 19 10 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 1132: ...Register Listing A 306 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 1192: ...Index I 34 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...