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1999 Dec 03
26
Philips Semiconductors
Preliminary specification
Digital TV sound demodulator/decoder
TDA9874A
10.3.1.1
Programming via subaddresses 0 to 24
While programming the TDA9874A, by writing to
subaddresses 0 to 24, it is not allowed to access
subaddress 255. Writing data to subaddress 255 will
overwrite the data previously written to subaddresses
3 to 10. This may cause unwanted effects.
10.3.1.2
Using Easy Standard Programming (ESP)
This facility simplifies programming by reducing the
amount of data to be set-up and transferred via the
I
2
C-bus.
Subaddress 255givescontrolofmoststandarddependent
settings of the IC; see ESP register in Section 10.3.23.
When using ESP it is recommended not to write data to
subaddresses 3 to 10.
A possible programming flow for using ESP and automatic
FM dematrixing (TVSM = 1 and IDSWFM = 1) is shown in
Table 12. It should be noted that the NICAM configuration
register and the level adjustment registers for FM and
NICAM are not affected by ESP.
Table 12
Programming the TDA9874A by using ESP and automatic FM dematrixing
REGISTER
CONTENT OF REGISTER
NUMBER
NAME
0
AGCCGR
set AGCGR = 20H for using the
10 dB attenuator at the SIF input, otherwise write a 00H to
this register
select the chosen SIF input pin by writing data to bit SIFSEL (bit 0) and choose the AGC
decay time corresponding to your application by writing the appropriate data to bit
AGCSLOW (bit 2)
set this register according to your sound mode detection algorithm
do NOT write data to these registers while using ESP
set FMMR = 80H to choose automatic FM dematrixing
see Table 38
see Table 39
set NCONR = 04H to select FM source automatically if NICAM is not available
see Table 42
set NLELR = 14H (default setting after Power-on reset) if no other value is chosen
set NUELR = 50H (default setting after Power-on reset) if no other value is chosen
set AMCONR = F9H to enable all analog outputs
Set SDACOSR = 81H to select +6 dB gain (see Table 48) and NICAM or FM output.
To select an internal source set AOSR = 80H to select dual A or set AOSR = C0H to select
dual B (if dual mode is transmitted) to all analog outputs. For selecting an external source
see Section 10.3.18.
use only for I
2
S-bus output, see detailed description in Section 10.3.19
use only for I
2
S-bus output, see detailed description in Section 10.3.20
use only for I
2
S-bus output, see detailed description in Section 10.3.21
MDACOSR Set MDACOSR = 82H to select dual A or set MDACOSR = 83H to select dual B (if dual
mode is transmitted) to all analog outputs. For selecting an external source see
Section 10.3.22.
ESP
see detailed description in Section 10.3.23
1
GCONR
2
3 to 10
11
12
13
14
15
16
17
18
19
20
MSR
FMMR
C1OLAR
C2OLAR
NCONR
NOLAR
NLELR
NUELR
AMCONR
SDACOSR
AOSR
21
22
23
24
DAICONR
I
2
SOSR
I
2
SOLAR
255