GC4016 Datasheet, PDF (48/83 Pages) Texas Instruments – MULTI-STANDARD QUAD DDC CHIP

GC4016 MULTI-STANDARD QUAD DDC CHIP
DATA SHEET REV 1.0
5.8 RESAMPLER CONTROL PAGE (PAGE 64)
This page controls the resampler. The address assignments are:
Table 17: Resampler Control Registers
ADDRESS
16
17
18
19
20
21
22
23
24-31
NAME
N-channels
N-Multiplies
Filter Select
Final Shift
Channel Map
Add To
Clock Divide
Ratio Map
Unused
DESCRIPTION
Sets the number of channels and filters
Sets the number of multiplies per output
Maps channels to filter sets
Sets the final gain shift
Maps channels to outputs
Adds channel outputs together
Divides the clock to the resampler
Maps ratios to output channels
ADDRESS 16: N-Channels Out Register, Suggested default = 0x23
BIT
0-1 LSB
TYPE
R/W
NAME
NC
2-3
R/W
NF
4-6
7 MSB
R/W
R/W
RES_SYNC
Unused
DESCRIPTION
Must be set to NC=NCHAN-1, where NCHAN is the number of output channels
to be generated. A value of NC=0 means one output channel. A value of NC=1
means two output channels. Use a value of NC=3 for either three or four output
channels. A value of 2 is illegal and will produce erroneous results.
Must be set to NF=NFILTER-1, where NFILTER is the number of resampler
filters. Used to partition the resampler coefficient RAM. A value of NF=0 means
one filter (normal case). A value of NF=1 means two filters. A value of NF=3
means four filters. A value of 2 is illegal.
The resampler is synchronized to this sync source (See Table 7). Resets the
delay accumulators in all channels at the same time.
ADDRESS 17: N-Multiplies Register, Suggested default = 0x0E
BIT
0-5 LSB
TYPE
R/W
NAME
NM
6
7 MSB
R/W
R/W
NO_SYM_RES
Unused
DESCRIPTION
Must be set to NM=NMULT-1, where NMULT is the number of resampler
multiplies. The minimum legal value is NM=5, the maximum is NM=63 but
typically the maximum will be set by other constraints (see Section 3.5). In the
case of a single channel output the minimum value is NM=6.
The resampler filter is presumed to be symmetric unless this bit is set.
ADDRESS 18: Filter Select Register, Suggested default = 0x00
BIT
0-1 LSB
2-3
4-5
6-7 MSB
TYPE
R/W
R/W
R/W
R/W
NAME
FILTER_SEL_0
FILTER_SEL_1
FILTER_SEL_2
FILTER_SEL_3
DESCRIPTION
The filter map for output channel 0. This select which of the NFILTER filters to
use for this channel. Must be less than or equal to NFILTER
The filter map for output channel 1.
The filter map for output channel 2.
The filter map for output channel 3.
© GRAYCHIP,INC.
- 43 -
August 27, 2001
This document contains information which may be changed at any time without notice