pnx1700 NXP Semiconductors, pnx1700 Datasheet - Page 553

• Manufacturer Part Number: pnx1700
• Description: Connected Media Processor
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Volume 1 of 1
PNX17XX_SER_1
Preliminary data sheet
Figure 1:
M
Serial Format of a IEC-60958 Block
channel 1
frame 191
3.3.1 IEC-60958 Serial Format
3.3 Data Formatting
W
Figure 1
special “B” preamble, and consists of 192 frames. The sample rate of all embedded
audio data is equal to the frame rate. Each frame consists of 2 subframes. Subframe
1 always starts with an “M” preamble, except for subframe 1 in frame 0, which starts
with a “B”. Subframe 2 always starts with a “W” preamble.
channel 2
When IEC-60958 data carries two-channel PCM data, one audio sample is
transmitted in each sub-frame, “left” in sub-frame 1 and “right” in sub-frame 2. Each
sample can be 16-24 bit, where the MSB is always aligned with bit slot 27 of the sub-
frame. In case of more than 20 bits per sample, the Aux field is used for the 4 LSB
bits.
When IEC-60958 data carries non-PCM audio, such as 1 or more streams of
encoded AC-3 data and/or MPEG audio, each sub-frame carries 16 bits data. The
data of successive frames adds up to a payload data-stream which carries its own
burst-data.
This is described in the “Interface for non-PCM Encoded Audio Bitstreams Applying
IEC958.” Philips Consumer Electronics, June 6 1997, IEC 100c/WG11 (preliminary
for IEC-61937).
shows the serial format layout of an IEC-60958 block. A block starts with a
pre-amble
pre-amble
B, W or M
B, W or M
0
0
B
sub-frame 1
channel 1
4
4
Aux.
Rev. 1 — 17 March 2006
frame 0
unused (0)
Start of block (indicated by unique B pre-amble)
W
sub-frame 2
L
S
B
8
8
channel 2
sub-frame (2 channel PCM)
sub-frame (non-PCM audio)
S
B
L
12
12
M
16
16
channel 1
Sample data
16 bits data
Channel status
Channel status
frame 1
20
20
Validity flag
Validity flag
User data
User data
W
Parity bit
Parity bit
channel 2
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
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Chapter 17: SPDIF Output
PNX17xx Series
M
M
S
B
S
B
M
28
V U C P
28
V U C P
channel 1
31
31
17-4