LF3320
DEVICES INCORPORATED
Horizontal Digital Image Filter
There are sixteen limit registers for Filter
A and sixteen for Filter B. Each register
is 32-bits wide and stores both an upper
and lower limit value. The lower limit is
stored in bits 15-0 and the upper limit is
stored in bits 31-16. RSLA3-0 and
RSLB3-0 determine which Filter A and B
limitregistersrespectivelyare used for
limiting when limiting is enabled.
Configuration and controlregister
loading is discussed in the LF
TABLE 6. CONFIGURATION REGISTER 4 – ADDRESS 204H
BITS
FUNCTION
DESCRIPTION
0
FilterBLimitEnable
0 : LimitingDisabled
1 : LimitingEnabled
1
FilterALimitEnable
Reserved
0 : LimitingDisabled
1 : LimitingEnabled
11-2
Must be set to “0”
TABLE 7. CONFIGURATION REGISTER 5 – ADDRESS 205H
InterfaceTM section.
BITS
FUNCTION
DESCRIPTION
LF InterfaceTM
0
Cascade Mode
0 : LastInLine
1 : FirstorMiddleinLine
The Filter A and B LF InterfacesTM are
used to load data into the Filter A and B
coefficient banks respectively. They are
also used to load data into the configu-
ration and control registers.
1
2
Single/DualFilterMode
FilterBInput
0 : Single Filter Mode
1 : DualFilterMode
0 : RIN11-0
1 : DIN11-0
3
Output Adder Control
Matrix Multiply Mode
AccumulatorAccessMode
Reserved
0 : Filter A + Filter B
The following section describes how
the Filter A LF InterfaceTM works. The
Filter A and BLF InterfacesTM are
identical in function. If LDA and
CFA11-0 are replaced with LDB and
CFB11-0, the following section will
describe how the Filter BLF InterfaceTM
works.
1 : Filter A + Filter B (Filter B Scaled by 2-12)
4
0 : Disabled
1 : Enabled
5
0 : Disabled
1 : Enabled
11-6
Must be set to “0”
The next value(s) loaded into the
interface are the data value(s) which
will be stored in the bank or register
defined by the address value. When
HIGH, theLFInterfaceTM affecting thedata
used for Filter B is held until PAUSEB is
returned to a LOW. Figures 19 through 22
display theeffectsofboth PAUSEA and
LDA is used to enable and disable the
Filter A LF InterfaceTM. When LDA goes
LOW, the Filter A LF InterfaceTM is
enabled for data input. The first value
fed into the interface on CFA11-0 is an
address which determines what the
interface is going to load. The three
most significant bits (CFA11-9) deter-
mine if the LF InterfaceTM will load
coefficient banks or
Configuration/ controlregisters (see
Table 8). The nine least significant bits
(CFA8-0) are the address for whatever
is to be loaded (see Tables 9 through
14). For example, to load address 15 of
the Filter A coefficient banks, the first
data value into the LF InterfaceTM
should be 00FH. To load Filter A limit
register 10, the first data value should
be C0AH. The first address value
should be loaded into the interface on
the same clock cycle that latches the
HIGH to LOW transition of LDA (see
Figures 17 and 18).
loading coefficient banks, the interface PAUSEB while loading coefficient and
will expect eight values to be loaded
into the device after the address value.
The eight values are coefficients 0
through 7. When loading configura-
tion or select registers, the interface
will expect one value after the address
value. When loading round or limit
registers, the interface will expect four
values after the address value. Figures
11 and 12 show the data loading
control data.
Table 15 shows an example of loading
data into the coefficient banks. The
following data values are written into
address 10 of coefficient banks 0
through 7: 210H, 543H, C76H, 9E3H,
701H, 832H, F20H, 143H. Table 16
shows an example of loading data into
a Configuration Register. Data value
003H is written into Configuration
Register 4. Table 17 shows an example
of loading data into a round register.
Data value 7683F4A2H is written into
Filter A round register 12.
sequences for the coefficient banks and
Configuration/ controlregisters.
Both PAUSEA and PAUSEB allow the
user to effectively slow the rate ofdata
loading through the LF InterfaceTM
When PAUSEA is HIGH, the LF
.
Table 18 shows an example of loading
data into a select register. Data value
00FH is loaded into Filter A select
InterfaceTM affecting the data used for
Filter A is held until PAUSEA is
register 2. Table 19 shows an example
returned to a LOW. When PAUSEB is
Video Imaging Products
08/16/2000–LDS.3320-N
2-15
LOGIC [ LOGIC DEVICES INCORPORATED ]
