saa2520 NXP Semiconductors, saa2520 Datasheet - Page 23

• Manufacturer Part Number: saa2520
• Description: Stereo Filter And Codec For Mpeg Layer 1 Audio Applications
• Manufacturer: NXP Semiconductors

Philips Semiconductors
I
The operation of the codec is controlled by the bits transferred in this mode.
Table 8 Internal Settings (LTCNT1 = logic 1, LTNCT 0 = logic 0).
Table 9 Internal Settings (LTCNT1 = logic 1, LTCNT0 = logic 0).
The bit rate index indicates the bit rate of the encoded
signal and is only effective in the encode mode.
The decode bit determines the operation mode of the
SAA2520. The default value is logic 1 (decoding mode).
EXT 256FS in the encoding mode determines whether or
not the SAA2520 is master or slave of the Filtered-I
interface (default is logic 0, master mode).
2CH MONO is used in the encoding mode to determine
whether the sub-band signal is generated as a stereo or
2-channel mono signal. Default value is logic 0.
MUTE is used in both the encoding and decoding modes
to mute the information to or from the Filtered-I
(the default value is logic 0).
August 1993
NTERNAL
S15
S11
S9
S8
S7
S6
S5
S4
S3
S1
Stereo filter and codec for MPEG layer 1
audio applications
msb
msb
1
1
0
0
S
ETTINGS
...
...
...
...
(LTCNT1 =
1
0
1
1
S12
S10
LOGIC
lsb
S2
S0
1, LTNCT 0 =
bit rate index
sample frequency
decode
EXT 256FS
2-channel mono
MUTE
CH1
Tr0 to Tr1
EMPHASIS
0
0
1
0
2
S interface
name
2
LOGIC
S
lsb
0
0
0
0
0)
23
CH1 is utilized in the decoding mode to select one of the
2-channel mono signals to be decoded (default is
I - channel 1). A value of 0 results in channel 2 being
decoded).
The transparent bits are copied in the sub-band signal,
default is 00.
The information from S15 to S10, S7 and S3 to S0 will be
copied into the sub-band signal.
bit rate indication
44.1, 48 or 32 kHz
indication
1 = decode; 0 = encode
1 = external;
0 = internal 256FS
1 = 2-CH mono;
0 = stereo
1 = mute; 0 = no mute
not used
1 = CH1; 0 = CH2
transparent bits
emphasis indication
384 kbits/s
256 kbits/s
192 kbits/s
128 kbits/s
function
bit rate
encode
encode
encode/decode
encode/decode
encode
encode/decode
decode
encode
encode
default value
Preliminary specification
valid in
SAA2520