MSP 44x8G
PRELIMINARY DATA SHEET
6.2. DSP Write and Read Registers for Manual 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
Additional Channel Matrix Modes
00 08
00 09
00 0A
00 41
00 0B
00 0C
[7:0]
[SUM/DIFF, AB_XCHANGE, PHASE_CHANGE_B,
PHASE_CHANGE_A, A_ONLY, B_ONLY]
00
79
hex
FM Fixed Deemphasis
FM Adaptive Deemphasis
Identification Mode
00 0F
[15:8]
[7:0]
[7:0]
[OFF, 50 µs, 75 µs]
[OFF, WP1]
OFF
OFF
B/G
79
79
79
00 15
[B/G, M]
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
80
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
80
80
hex
hex
[8000 ... 7FFF
]
hex
hex
6.3. Manual Mode:
Selected Sound
NICAM
Description of Demodulator Write Registers
6.3.1. Automatic Switching between NICAM and
Analog Sound
In case of bad NICAM reception or loss of the
NICAM-carrier, the MSP 44x8G 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: 0023hex) provide information about the actual
NICAM-FM/AM-status.
– NICAM → analog sound if ERROR_RATE > 700
– analog sound → NICAM if ERROR_RATE < 700/2
74
Micronas
MICRONAS [ MICRONAS ]
