cs49329 Cirrus Logic, Inc., cs49329 Datasheet - Page 77

• Manufacturer Part Number: cs49329
• Description: Multi-standard Audio Decoder Family
• Manufacturer: Cirrus Logic, Inc.

11.2.1. Input Configuration
1) 24-bit PCM input requires at least 24 SCLKS
DS339F7
84
0
(default)
1
B Value
C Value
per sub-frame. The DSP always uses 24-bit
resolution for PCM input. Systems having less
than 24-bit resolution will not have a problem
as the extra bits taken by the DSP will be under
Table 20. Input SCLK Polarity Configuration
Table 19. Input Data Format Configuration
Considerations
(Input Parameter B) (Continued)
PCM - Left Justified 24-bit
Multichannel PCM (4 Channel)
- Left Justified 20-bit
(used only by special post-processing
application codes)
Data Clocked in on Rising
Edge
Data Clocked in on Falling
Edge
SCLK Polarity (Both CDI &
(Input Parameter C)
Data Format
DAI Port)
0x800217
0x8080FF
0x80021A
0x8080FF
0x800117
0x0028C0
0x80011A
0x0018C0
0x800217
0xFFFFDF
0x80021A
0xFFFFDF
0x800117
0x000020
0x80011A
0x000020
Message
Message
Hex
Hex
2) If the clocks to the audio ports are known to be
1
2
D Value
the noise floor of the input signal for left justified
and I
always taken in 16 bit word lengths.
corrupted, such as when a S/PDIF receiver
goes out of lock, the DSP should undergo an
application restart (if applicable), soft reset or
hard reset. All three actions will result in the
input FIFO being reset. Failure to do so may
result in corrupted data being latched into the
input FIFO and may result in corrupted data
being heard on the outputs. This is not an issue
when compressed data is being delivered, as it
has sync words embedded in the stream which
the DSP can lock to, but only when PCM data
is being delivered. Certain application codes
that are capable of processing PCM may now
have
Robustness” which does alleviate the above
problem, however you should still follow the
above recommendation.
Table 21. Input FIFO Setup Configuration
2
Compressed FIFO B Size -
6kbyte
Blocksize - up to 2kbyte
PCM FIFO C Size - 6kbyte
Blocksize - up to 2kbyte
S formats. For compressed input, data is
default - only applicable to
FIFO Size & Blocksize (no
a
parallel delivery modes)
(Input Parameter D)
special
CS49300 Family DSP
feature
called
0x800014
0x280D00
0x800014
0x820300
Message
Hex
“PCM
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