TDA9874A Philips Semiconductors, TDA9874A Datasheet - Page 53

• Manufacturer Part Number: TDA9874A
• Description: Digital TV sound demodulator/decoder
• Manufacturer: Philips Semiconductors

Philips Semiconductors
10.4.1
Table 75 Device status register (subaddress 0)
Table 76 Description of the DSR bits
10.4.2
Table 77 NICAM status register (subaddress 1)
1999 Dec 03
Digital TV sound demodulator/decoder
P2IN
BIT
C4
7
7
6
5
4
3
2
1
0
7
D
NICAM S
EVICE
S
SYMBOL
AMSTAT
TATUS
TATUS
IDDUA
IDSTE
RSSF
VDSP
P1IN
P2IN
P1IN
PFR
C3
6
6
R
R
EGISTER
EGISTER
Input from Port 2: this bit reflects the status of the P2 general purpose port pin;
see Section 10.3.3. If P2IN = 1, then the P2 general purpose port pin is HIGH.
If P2IN = 0, then the P2 general purpose port pin is LOW.
Input from Port 1: this bit reflects the status of the P1 general purpose port pin;
see Section 10.3.3. If P1IN = 1, then the P1 general purpose port pin is HIGH.
If P1IN = 0, then the P1 general purpose port pin is LOW.
Reserve Sound Switching Flag: when RSSF = 1, this bit is a copy of the C4 bit in the
NICAM status register (see Section 10.4.2). It indicates that the FM (or AM for
standard L) sound matches the digital transmission and auto-muting should be enabled.
When RSSF = 0, auto-muting should be disabled, as analog and digital sound are
different.
Auto-mute Status: if this bit is HIGH, it indicates that the auto-muting function has
switched from NICAM to the program of the first sound carrier (i.e. FM mono or AM in
NICAM L systems)
Identification of NICAM sound: when VDSP = 1, it indicates that digital transmission
is a sound source. When VDSP = 0, it indicates that the transmission is either data or a
currently undefined format.
Identification of FM dual sound; A2 systems: if IDDUA = 1, an FM dual-language
signal has been identified. When neither IDSTE nor IDDUA = 1, the received signal is
assumed to be FM mono (A2 systems only).
Identification of FM stereo; A2 systems: if IDSTE = 1, an FM stereo signal has been
identified (A2 systems only)
Power failure register: the power supply for the digital part of the device (V
temporarily been lower than the specified lower limit. If this is detected an initialization of
the device has to be carried out to ensure reliable operation.
RSSF
(DSR)
(NISR)
C2
5
5
AMSTAT
C1
4
4
53
VDSP
OSB
3
3
DESCRIPTION
IDDUA
CFC
2
2
IDSTE
S/MB
Preliminary specification
1
1
TDA9874A
DDD1
D/SB
PFR
0
0
) has