MSP 3400C
PRELIMINARY DATA SHEET
4.2. Analog Section and SCART Switching Facilities
4.3. MSP 3400C Audio Baseband Processing
By means of the DFP processor, all audio baseband
functions are performed by digital signal processing
(DSP). The DSP functions are grouped into three pro-
cessing parts: input preprocessing, channel selection,
and channel postprocessing.
The analog input and output sections offer a wide range
of switching facilities, which are shown in Fig. 4–3. To
design a TV-set with 3 pairs of SCART-inputs and two
pairsofSCART-outputs, noexternalswitchinghardware
is required.
The input preprocessing is intended to prepare the vari-
ous signals of all input sources in order to form a stan-
dardized signal at the input to the channel selector. The
signals can be adjusted in volume, are processed with
the appropriate deemphasis, and are dematrixed if nec-
essary.
The switches are controlled by the ACB bits defined in
the audio processing interface (see section 7. Program-
ming the Audio Processing Part).
If the MSP 3400C is switched off by first pulling STAND-
BYQ low, and then disconnecting the 5 V, but keeping
the 8 V power supply (‘Standby’-mode), the switches
S1, S2, and S3 maintain their position and function. This
facilitates the copying from selected SCART-inputs to
SCART-outputs in the TV-sets standby mode.
Havingpreparedthesignalsthatway, thechannelselec-
tor makes it possible to distribute all possible source sig-
nals to the desired output channels.
The ability to route in an external coprocessor for special
effects like surround and sound field processing is of
specialimportance. Routingcanbedonewitheachinput
source and output channel via the I S inputs and out-
puts.
SCART_IN
ACB[1:0]
2
SC1_IN_L/R
2
2
2
2
00
01
to Audio Baseband
Processing (DFP)
MONO
A
D
2
SC2_IN_L/R
SCARTL/R
All input and output signals can be processed simulta-
neously. Note that the NICAM input signals are only
availablein the MSP 3410 version. While processing the
adaptive deemphasis, no dual carrier stereo (German or
Korean) is possible. Identification values are not valid ei-
ther.
10
SC3_IN_L/R
11
S1
ACB[3:2]
2
2
2
2
00
01
SCART_OUT
2
from Audio Baseband
Processing (DFP)
SC1_OUT_L/R
10
4.3.1. Dual Carrier FM Stereo/Bilingual Detection
D
SCARTL/R
2
A
11
S2
In the German and Korean TV standard, audio informa-
tion can be transmitted in three modes: mono, stereo, or
bilingual. To obtain information about the current audio
operation mode, the MSP 3400C detects the so-called
identification signal. Information is supplied via the Ste-
reo Detection Register to an external CCU.
ACB[5:4]
00
01
2
2
2
2
SC2_OUT_L/R
S3
10
Fig. 4–3: SCART-Switching Facilities
Bold lines determine the default configuration
Stereo
Level
Detection
Detect
Filter
Stereo
Detection
Register
AM
Demodu-
lation
IDENT
–
In case of power-on start or starting from standby, the IC
switches automatically to the default configuration,
shown in Fig. 4–3. This takes place after the first I C
Bilingual
Detection
Filter
Level
Detect
2
transmission into the DFP part. By transmitting the ACB
register first, the default setting mode can be changed.
Fig. 4–4: Stereo/bilingual detection
MICRONAS INTERMETALL
11
MICRONAS [ MICRONAS ]
