SAA7283ZP datasheet(19/36 Pages) PHILIPS

19 / 36 page

1996 Oct 24

Philips Semiconductors

Preliminary speciﬁcation

Terrestrial Digital Sound Decoder (TDSD3)

SAA7283

Channel coding

Time-slots are encoded as biphase mark data. Each bit

transmitted is represented by a symbol comprising two

consecutive binary states. The first state of a symbol is

always different from the second state of the previous

symbol. The second state of the symbol is identical to the

first if the bit being transmitted is logic 0, however it is

different if the bit is logic 1 (see Table 14).

Table 14 Channel coding

Preambles

Preambles are specific patterns providing synchronization

and identification of the sub-frames and blocks.

A set of three preambles is used. These preambles are

transmitted in the time allocated to four time-slots and are

represented by eight successive states. The first state of

the preamble is always different from the second state of

the previous symbol. Depending on this state the

preambles are as shown in Table 15.

PRECEDING STATE

TRANSMITTED BIT

CHANNEL CODING

011

110

Table 15 Preambles

The preambles preceding each digital audio sample are

used to indicate the beginning of a sample as follows:

• Preamble B indicates the start of Channel A data and

the beginning of a block

• Preamble M indicates the start of Channel A data but

not the beginning of a block

• Preamble W indicates the start of Channel B data.

Channel status

The channel status information is organized in 192-bit

words. The first bit of each word is carried in the frame with

Preamble B. The 192-bit word is organized into sections

as shown in Table 16.

PRECEDING STATE

PREAMBLE

CHANNEL CODING

11101000

00010111

11100010

00011101

11100100

00011011

Table 16 Channel status codes

BIT

CODE

DESCRIPTION

consumer

sound data

digital copy permitted

3 and 4

indicates digital de-emphasis switched in

indicates digital de-emphasis switched out

−

6 and 7

−

8 to 5

00110001

category code

16 to 19

0000

source code (don't care)

20 to 23

0000

channel number (don't care)

24 to 27

1100

sampling frequency (32 kHz)

28 and 29

clock accuracy (level II)

30 to 191

all 0s

−

SAA7283ZP bảng dữ liệu(PDF) 19 Page - NXP Semiconductors

SAA7283ZP bảng dữ liệu(HTML) 19 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

bảng dữ liệu tải về

Link URL