L64780 LSI Logic Corporation, L64780 Datasheet - Page 69

• Manufacturer Part Number: L64780
• Description: Dvb-t Cofdm Demodulator Technical Manual 2/00
• Manufacturer: LSI Logic Corporation

AFC_MODE
AFC_FINE_MODE
AFC_STALL
Parameter Registers
If not, the value applied to the Tuner Oscillator (via the
Sigma-Delta) is either +1 or 1. This limits the bandwidth
of the system.
The initial condition for the AFC_CLIPPING bit is 1, which
is Method II.
AFC Muxin Mode
When the MUXIN bus is connected to the AFC, this bit
determines if the Symbol Number is coming from the
OBC (Partial MUXIN Mode), as in Normal functional
mode, or coming from the MUXIN bus itself (Full MUXIN
Mode). If this bit is 0, the Symbol Number is coming from
the Full MUXIN Mode; if this bit is 1, the Symbol Number
is coming from the Partial MUXIN Mode.
The initial condition for the AFC_MODE is 0, the Full
MUXIN mode. However, this has no effect if the default
mode of AFC_MUXIN is 0 (which means that the AFC is
taking its Symbol Number from the OBC no matter what
the value of AFC_MODE is). See the definition of the
MUXIN register for more information.
AFC Fine Algorithm Mode
This bit determines if the AFC Fine Algorithm performs a
weighted mean.
If the Weighted mean mode is chosen (this bit is 0), the
AFC algorithm performs a weighted mean on the signal
measurements to perform its Fine AFC calculation.
If the Unweighted mean mode is chosen (this bit is 1), the
AFC algorithm does not perform a weighted mean on the
signal measurements to perform its Fine AFC calculation.
The initial condition for this bit is 0, the Weighted Mean
mode.
AFC Loop Updating Freeze
This bit determines if the AFC Loop is working or frozen.
If the Loop is working (0), the integrator inside the
L64780 updates its value from time to time.
R/W 6
R/W 5
R/W 4
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