LF3320QC15 LODEV [LOGIC Devices Incorporated], LF3320QC15 Datasheet - Page 14

• Manufacturer Part Number: LF3320QC15
• Description: Horizontal Digital Image Filter
• Manufacturer: LODEV [LOGIC Devices Incorporated]

DEVICES INCORPORATED
Output Limiting
An output limiting function is provided for
the overall filter, Filter A, and Filter B
outputs. The Filter A limiting circuitry is
used to limit the overall 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
T
T
ABLE
ABLE
BITS
BITS
11-3
11-7
4-1
0
1
2
0
5
6
4. C
5. C
Reserved
Reserved
FUNCTION
ALU Mode Filter B
Pass A Filter B
Pass B Filter B
FUNCTION
Filter B Odd-Tap
Interleave Mode
Filter B I/D Register Length
Filter B Tap Number
Filter B Data Reversal
ONFIGURATION
ONFIGURATION
R
R
EGISTER
EGISTER
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”
0 : Odd-Tap Interleave Mode Disabled
1 : Odd-Tap Interleave Mode Enabled
0000 :
0001 :
0010 :
0011 :
0100 :
0101 :
0110 :
0111 :
1000 :
1001 :
1010 :
1011 :
1100 :
1101 :
1110 :
1111 :
0 : Even Number of Taps
1 : Odd Number of Taps
0 : Data Reversal Enabled
1 : Data Reversal Disabled
Must be set to “0”
DESCRIPTION
DESCRIPTION
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
Filter A limit registers are used in the Filter
A limit circuitry. RSLB
which of the sixteen Filter B limit
registers are used in the Filter B limit
circuitry. A value of 0 on
RSLA/RSLB
register 0. A value of 1 selects Filter A/B
limit register 1 and so on. Each limit
2 – A
3 – A
3-0
DDRESS
DDRESS
determines which of the sixteen
3-0
1 0 Registers
1 1 Registers
1 2 Registers
1 3 Registers
1 4 Registers
1 5 Registers
1 6 Registers
1 Register
2 Registers
3 Registers
4 Registers
5 Registers
6 Registers
7 Registers
8 Registers
9 Registers
selects Filter A/B limit
202H
203H
2-14
3-0
determines
Horizontal Digital Image Filter
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 respec-
tively. RSLA/RSLB
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 coeffi-
cients 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
banks are loaded using an LF
Interface
Interface
banks. Coefficient bank loading is
discussed in the LF Interface
section.
Configuration and Control Registers
The configuration registers determine
how the LF3320 operates. Tables 2
through 7 show the formats of the six
configuration registers. There are three
types of control registers: round, select,
and limit. There are sixteen round
registers for Filter A and sixteen for
Filter B. Each register is 32 bits wide.
RSLA
Filter A and B round registers respec-
tively are used for rounding.
There are sixteen select registers for
Filter A and sixteen for Filter B. Each
register is 5 bits wide. RSLA
RSLB
select registers respectively are used in
the select circuitry.
Video Imaging Products
3-0
3-0
determine which Filter A and B
and RSLB
TM
TM
. There is a separate LF
for the Filter A and B
TM
section.
3-0
3-0
determine which
may be changed
08/16/2000–LDS.3320-N
LF3320
3-0
TM
and