SAA2520 Datasheet, PDF (24/36 Pages) NXP Semiconductors – Stereo filter and codec for MPEG layer 1 audio applications

Philips Semiconductors
Stereo filter and codec for MPEG layer 1
audio applications
Preliminary specification
SAA2520
Table 10 Sample frequency indication.
msb
0
0
1
1
Table 11 EMPHASIS indication.
msb
0
0
1
1
lsb
sample frequency
0
44.1 kHz
default value
1
48 kHz
0
32 kHz
1
not used
lsb
emphasis
0
no emphasis
1
50/15 µs
0
reserved
1
CCITT J.17
default value
Before sending internal settings the microcontroller should
check whether or not the SAA2520 is ready-to-receive.
However, this does not apply for the transfer of internal
settings to end a transfer of allocation information.
STATUS (LTCNT = LOGIC 1, LTNCT0 = LOGIC 1)
Table 12 Status information 16-bit units.
msb
T15
...
T11
...
T9
T8
T7
T5
T4
T3
T1
...
lsb
name
T12 bit rate index
T10 sample frequency
ready-to-receive
not used
T6 MODE
SYNC
CLKOK
T2 Tr0 to Tr1
T0 EMPHASIS
function
bit rate indication
44.1, 48 or 32 kHz indication
1 = ready; 0 = not ready
valid in
encode/decode
encode/decode
encode/decode
sub-band signal mode indication
synchronization indication
1 = o.k.; 0 = not o.k.
transparent bits
emphasis indication
encode/decode
decode
encode/decode
encode/decode
encode/decode
The bit rate index indicates the bit rate of the sub-band
signal in units of 32 kbits/s. bit rate index 0000 indicates
the ‘free format’ condition. bit rate 1111 is illegal and
should not be found.
The coding of the sample frequency indication is equal
to the one in the internal settings.
August 1993
24