tda9874h NXP Semiconductors, tda9874h Datasheet - Page 36

• Manufacturer Part Number: tda9874h
• Description: Digital Tv Sound Demodulator/decoder
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7.4.1
Table 58 Device status register (subaddress 0)
Table 59 Description of the device status register bits
2000 Jun 26
Digital TV sound demodulator/decoder
P2IN
BIT
7
7
6
5
4
3
2
1
0
D
EVICE STATUS REGISTER
SYMBOL
AMSTAT
IDDUA
IDSTE
RSSF
VDSP
P1IN
P2IN
P1IN
6
Input from Port 2: this bit reflects the status of the general purpose port pin P2;
see Section 7.3.2. If bit P2IN = 1 the general purpose port pin P2 is at HIGH level.
If bit P2IN = 0 the general purpose port pin P2 is at LOW level.
Input from Port 1: this bit reflects the status of the general purpose port pin P1;
see Section 7.3.2. If bit P1IN = 1 the general purpose port pin P1 is at HIGH level.
If bit P1IN = 0 the general purpose port pin P1 is at LOW level.
Reserve Sound Switching Flag: if bit RSSF = 1 it is a copy of bit C4 in the NICAM Status
Register (see Section 7.4.2). It indicates that the FM (or AM for standard L) sound
matches the digital transmission and auto-muting should be enabled. If bit RSSF = 0
auto-muting should be disabled as analog and digital sound are different.
Auto-mute Status: if this bit is 1, 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: bit VDSP = 1 indicates that digital transmission is a
sound source. Bit VDSP = 0 indicates the transmission is either data or a currently
undefined format.
Identification of FM dual sound; A2 systems: if bit IDDUA = 1, an FM dual-language
signal has been identified. If neither bit IDSTE nor IDDUA = 1 the received signal is
assumed to be FM mono (A2 systems only).
Identification of FM stereo; A2 systems; if bit IDSTE = 1 an FM stereo signal has been
identified (A2 systems only).
value is undefined
RSSF
5
AMSTAT
4
36
VDSP
3
DESCRIPTION
IDDUA
2
IDSTE
1
Product specification
TDA9874H
0