lf3320 LOGIC Devices Incorporated, lf3320 Datasheet - Page 14

• Manufacturer Part Number: lf3320
• Description: Horizontal Digital Image Filter
• Manufacturer: LOGIC Devices Incorporated

DEVICES INCORPORATED
The Filter A select registers are used
for the overall filter (Single Filter
Mode) or Filter A (Dual Filter Mode).
The Filter B select registers are used
for Filter B (Dual Filter Mode). Each
select register is 5 bits wide and user-
programmable. RSLA
which of the sixteen Filter A select reg-
isters are used in the Filter A select
circuitry. RSLB
of the sixteen Filter B select registers
are used in the Filter B select circuitry.
A value of 0 on RSLA/RSLB
Filter A/B select register 0. A value
T
T
ABLE
ABLE
BITS
BITS
11-3
11-7
4-1
0
1
2
0
5
6
4. C
5. C
FUNCTION
ALU Mode Filter B
Pass A Filter B
Pass B Filter B
Reserved
FUNCTION
Filter B Odd-Tap
Interleave Mode
Filter B I/D Register Length
Filter B Tap Number
Filter B Data Reversal
Reserved
3-0
ONFIGURATION
ONFIGURATION
determines which
3-0
determines
3-0
R
R
selects
EGISTER
EGISTER
DESCRIPTION
0 : A + B
1 : B – A
0 : ALU Input A = 0
1 : ALU Input A = Forward Register Path
0 : ALU Input B = 0
1 : ALU Input B = Reverse Register Path
Must be set to “0”
DESCRIPTION
0 : Odd-Tap Interleave Mode Disabled
1 : Odd-Tap Interleave Mode Enabled
0000:
0001:
0010:
0011:
0100:
0101:
0110:
0111:
1000:
1001: 1
1010: 1
1011: 1
1100: 1
1101: 1
1110: 1
1111: 1
0 : Even Number of Taps
1 : Odd Number of Taps
0 : Data Reversal Enabled
1 : Data Reversal Disabled
Must be set to “0”
of 1 selects Filter A/B select register
1 and so on. RSLA/RSLB
changed every clock cycle if desired.
This allows the 16-bit window to be
changed every clock cycle. This is
useful when filtering interleaved data.
Select register loading is discussed in
the LF Interface
Output Limiting
An output limiting function is pro-
vided for the overall filter, Filter A,
and Filter B outputs. The Filter A lim-
2 – A
3 – A
DDRESS
DDRESS
1 Register
2 Registers
3 Registers
4 Registers
5 Registers
6 Registers
7 Registers
8 Registers
9 Registers
0 Registers
1 Registers
2 Registers
3 Registers
4 Registers
5 Registers
6 Registers
TM
202H
203H
2-14
section.
3-0
may be
Horizontal Digital Image Filter
iting circuitry is used to limit the over-
all filter output (Single Filter Mode)
and the Filter A output (Dual Filter
Mode). The Filter B limiting circuitry
is used to limit the Filter B output
(Dual Filter Mode). The Filter A and B
limit registers determine the valid
range of output values for the Filter A
and B limiting circuitry respectively.
There are sixteen 32-bit
user-programmable limit registers for
both Filters A and B. The Filter A
limit registers are used for the overall
filter (Single Filter Mode) or Filter A
(Dual Filter Mode). The Filter B limit
registers are used for Filter B (Dual
Filter Mode). RSLA
which of the sixteen Filter A limit reg-
isters are used in the Filter A limit
circuitry. RSLB
of the sixteen Filter B limit registers
are used in the Filter B limit circuitry.
A value of 0 on RSLA/RSLB
Filter A/B limit register 0. A value of
1 selects Filter A/B limit register 1 and
so on. Each limit register contains an
upper and lower limit value. If the
value fed to the limiting circuitry is
less than the lower limit, the lower
limit value is passed as the filter
output. If the value fed to the limiting
circuitry is greater than the upper
limit, the upper limit value is passed
as the filter output. Bit 1 and 0
in Configuration Register 4 enable
and disable Filter A and B limiting
respectively. RSLA/RSLB
changed every clock cycle if desired.
This allows the limit range to be
changed every clock cycle. This
is useful when filtering interleaved
data. When loading limit values into
the device, the upper limit must be
greater than the lower limit. Limit
register loading is discussed in the LF
Interface
Coefficient Banks
The coefficient banks store the coef-
ficients which feed into the multipliers
in Filters A and B. There is a separate
bank for each multiplier. Each bank
can hold 256 12-bit coefficients. The
Video Imaging Products
TM
section.
3-0
determines which
3-0
determines
6/22/2007–LDS.3320-R
3-0
LF3320
3-0
may be
selects