PRELIMINARY DATA SHEET
MSP 34x2G
6.2. DSP Write and Read Registers for Manual/Compatibility Mode
Table 6–3: DSP-Write Registers; Subaddress: 12hex, all registers are readable as well
Write Register
Address Bits
(hex)
Operational Modes and Adjustable Range
Reset
Mode
Page
Volume SCART1 channel: Ctrl. mode
FM Fixed Deemphasis
00 07
00 0F
[7..0]
[15..8]
[7..0]
[7..0]
[7..0]
[7..0]
[Linear mode / logarithmic mode]
[50 µs, 75 µs, OFF]
[OFF, WP1]
00
97
97
97
98
98
97
hex
50 µs
OFF
B/G
FM Adaptive Deemphasis
Identification Mode
00 15
00 17
00 40
[B/G, M]
FM DC Notch
[ON, OFF]
ON
Volume SCART2 channel: Ctrl. mode
[Linear mode / logarithmic mode]
00
hex
Table 6–4: DSP Read Registers; Subaddress: 13hex, all registers are not writable
Additional Read Registers
Address Bits
(hex)
Output Range
Page
Stereo detection register for
A2 Stereo Systems
00 18
[15..8]
[80 ... 7F
]
8 bit two’s complement
98
hex
hex
DC level readout FM1/Ch2-L
DC level readout FM2/Ch1-R
00 1B
00 1C
[15..0]
[15..0]
[8000 ... 7FFF
]
16 bit two’s complement
16 bit two’s complement
98
98
hex
hex
[8000 ... 7FFF
]
hex
hex
6.3. Manual/Compatibility Mode:
Description of Demodulator Write Registers
Selected Sound
NICAM
6.3.1. Automatic Switching between NICAM and
Analog Sound
In case of bad NICAM reception or loss of the
NICAM-carrier, the MSP 34x2G offers an Automatic
Switching (fall back) to the analog sound (FM/AM-
Mono), without the necessity of the controller reading
and evaluating any parameters. If a proper NICAM sig-
nal returns, switching back to this source is performed
automatically as well. The feature evaluates the NICAM
ERROR_RATE and switches, if necessary, all output
channels which are assigned to the NICAM source, to
the analog source, and vice versa.
analog
Sound
ERROR_RATE
threshold/2
threshold
Fig. 6–1: Hysteresis for Automatic Switching
6.3.1.1. Function in Automatic Sound Select Mode
The Automatic Sound Select feature (MODUS[0]=1)
includes the procedure mentioned above. By default, the
internal ERROR_RATE threshold is set to 700dec. i.e. :
An appropriate hysteresis algorithm avoids oscillating
effects (see Fig. 6–1). STATUS[9] and C_AD_BITS[11]
(Addr: 0023 hex) provide information about the actual
NICAM-FM/AM-status.
– NICAM → analog Sound if ERROR_RATE > 700
– analog Sound → NICAM if ERROR_RATE < 700/2
The ERROR_RATE value of 700 corresponds to a
BER of approximately 5.46*10-3/s.
Micronas
87
MICRONAS [ MICRONAS ]
