PRELIMINARY DATA SHEET
MSP 34x7G
6.4. Manual/Compatibility Mode:
Table 6–16: NICAM operation modes as defined by
Description of Demodulator Read Registers
the EBU NICAM 728 specification
Note: The use of these register is no longer recom-
mended. It should be used only in cases where soft-
ware compatibility to the MSP 34x7D is required.
Using the STANDARD SELECTION register together
with the STATUS register provides a more economic
way to program the MSP 34x7G and to retrieve infor-
mation from the IC.
C4 C3 C2 C1 Operation Mode
0
0
0
0
0
0
0
0
1
0
1
0
Stereo sound (NICAMA/B),
independent mono sound (FM1)
Two independent mono signals
(NICAMA, FM1)
Three independent mono channels
(NICAMA, NICAMB, FM1)
All registers except C_AD_BITs are 8 bit wide. They
can be read out of the RAM of the MSP 34x7G if the
MSP 34x7D compatibility mode is required.
0
1
0
0
1
0
1
0
Data transmission only; no audio
Stereo sound (NICAMA/B), FM1
carries same channel
All transmissions take place in 16-bit words. The valid
8-bit data are the 8 LSBs of the received data word.
1
1
0
0
0
1
1
0
One mono signal (NICAMA). FM1
carries same channel as NICAMA
If the Automatic Sound Select feature is not used, the
NICAM or FM-identification parameters must be read
and evaluated by the controller in order to enable
appropriate switching of the channel select matrix of
the baseband processing part. The FM-identification
registers are described in Section 6.6.1. To handle the
NICAM-sound and to observe the NICAM-quality, at
least the registers C_AD_BITS and ERROR_RATE
must be read and evaluated by the controller. Addi-
tional data bits and CIB bits, if supplied by the NICAM
transmitter, can be obtained by reading the registers
ADD_BITS and CIB_BITS.
Two independent mono channels
(NICAMA, NICAMB). FM1 carries
same channel as NICAMA
1
x
0
1
1
x
1
x
Data transmission only; no audio
Unimplemented sound coding
option (not yet defined by EBU
NICAM 728 specification)
AUTO_FM: monitor bit for the AUTO_FM Status:
0: NICAM source is NICAM
1: NICAM source is FM
Note: It is no longer necessary to read out and evalu-
ate the C_AD_BITS. All evaluation is performed in the
MSP and indicated in the STATUS register.
6.4.1. NICAM Mode Control/Additional Data Bits
Register
NICAM operation mode control bits and A[2:0] of the
additional data bits.
6.4.2. Additional Data Bits Register
Format:
Contains the remaining 8 of the 11 additional data bits.
The additional data bits are not yet defined by the
NICAM 728 system.
MSB
C_AD_BITS 00 23hex
LSB
11
...
...
7
6
5
4
3
2
1
0
Auto
_FM
A[2] A[1] A[0]
C4
C3
C2
C1
S
Format:
MSB
7
ADD_BITS 00 38hex
LSB
0
6
5
4
3
2
1
Important: “S” = bit[0] indicates correct NICAM-syn-
chronization (S = 1). If S = 0, the MSP 3417/3457G
has not yet synchronized correctly to frame and
sequence, or has lost synchronization. The remaining
read registers are therefore not valid. The MSP mutes
the NICAM output automatically and tries to synchro-
nize again as long as MODE_REG[6] is set.
A[10]
A[9]
A[8]
A[7]
A[6]
A[5]
A[4]
A[3]
6.4.3. CIB Bits Register
Cib bits 1 and 2 (see NICAM 728 specifications).
Format:
The operation mode is coded by C4-C1 as shown in
Table 6–16.
MSB
CIB_BITS 00 3Ehex
LSB
0
7
x
6
x
5
x
4
x
3
x
2
x
1
CIB1
CIB2
Micronas
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