Cirrus Logic AN333 User Manual

Page 21

AN333

4.4 Unsolicited Messages

Table 4-7. Autodetect Messages

Index

Variable

Description

0x0000

AUTODETECT_RESPONSE

Bit 31 = Decodable_Stream_Flag= 0/1 = This stream is not/is decodable by the
application (no need for new download if 1).
Bit 5 Non_IEC61937_Stream_Flag= 1/0 = This stream is not/is IEC61937 compressed
data.
If Non_IEC61937_Stream_Flag=1
Bits [4:0] = Non_IEC61937 Stream Descriptor.

0x00 = Silent Input Data (Out of Application Sync).
0x01 = DTS Format-16 elementary stream.
0x02 = DTS Format-14 elementary stream.
0x03 = Linear PCM stream.
0x04 = HDCD PCM Sync Detect (only available in HDCD application).
0x05 = HDCD PCM Sync Lost (only available in HDCD application).

If Non_IEC61937_Stream_Flag=0
Bits [4:0] = IEC61937 Stream Descriptor = Identical to bits [4:0] of the Pc burst
data-type descriptor in IEC61937 specification. Description of the data-type field of Pc
reproduced below from IEC61937 Specification (current as of 11/97):

0x00 = Never Reported.
0x01 = AC-3 data.
0x03 = Never Reported.
0x04 = MPEG-1 Layer 1 data.
0x05 = MPEG-1 Layer 2 or 3 data or MPEG-2 without extension.
0x06 = MPEG-2 data with extension.
0x07 = MPEG-2 AAC ADTS data.
0x08 = MPEG-2 Layer 1 Low sampling frequency.
0x09 = MPEG-2 Layer 2 or 3 Low sampling frequency.
0x0B = DTS-1 data (512-sample bursts).
0x0C = DTS-2 data (1024-sample bursts).
0x0D = DTS-3 data (2048-sample bursts).
0x0E - 0x1B = Reserved.
0x1C = MPEG-2 AAC ADTS data.