HMP8112 Datasheet, PDF (16/40 Pages) Harris Corporation – NTSC/PAL Video Decoder

HMP8112
BIT
NUMBER
FUNCTION
7-0
Color Saturation
Adjust Factor
TABLE 11. COLOR SATURATION ADJUST FACTOR
DESTINATION ADDRESS = 05_H
DESCRIPTION
RESET
STATE
This register sets the color saturation adjust factor. This value is multiplied by the chromi-
nance (CbCr) data and allows the data to be scaled from 0 to a factor of +1.96875. This 8-bit
number is a fractional number as shown below:
2⁰ 2^-1 2^-2 2^-3 2^-4 2^-5 2^-6 2^-7
The contrast factor is applied after the brightness.
1001 1101_B
TABLE 12. PHASE LOCKED LOOP CHROMINANCE SUBCARRIER TO BUS CLOCK FREQUENCY RATIO
BIT
NUMBER
FUNCTION
DESTINATION ADDRESS = 06_H
DESCRIPTION
RESET
STATE
7-0
Chroma PLL Ratio
These bits are used to program the ratio of the incoming video chrominance color sub-
carrier frequency to the BUS Clock used. This number serves as the reference frequency
of the chrominance PLL and must be very accurate. This is the lower byte of the ratio and
encompasses the following range:
2^-9 2^-10 2^-11 2^-12 2^-13 2^-14 2^-15 2^-16
The default value is for a CLK frequency of 27MHz and a color subcarrier of 3.579545
MHz.
1100 0001_B
TABLE 13. PHASE LOCKED LOOP CHROMINANCE SUBCARRIER TO BUS CLOCK FREQUENCY RATIO
BIT
NUMBER
FUNCTION
DESTINATION ADDRESS = 07_H
DESCRIPTION
RESET
STATE
15 - 8
Chroma PLL Ratio
These bits are used to program the ratio of the incoming video chrominance color sub-
carrier frequency to the BUS Clock used. This number serves as the reference frequency
of the chrominance PLL and must be very accurate. This is the upper byte of the ratio
and encompasses the following range:
2^-1 2^-2 2^-3 2^-4 2^-5 2^-6 2^-7 2^-8
1000 0111_B
TABLE 14. HORIZONTAL AGC START TIME REGISTER
BIT
NUMBER
FUNCTION
DESTINATION ADDRESS = 08_H
DESCRIPTION
RESET
STATE
7-0
Horizontal AGC
This register provides a programmable delay for the HAGC pulse that control the sync
Pulse Programmable tip AGC in the A/D converters. The start time of the HAGC pulse is set from the detection
Start Time
of horizontal sync in the video data. HAGC is programmable in CLK increments and has
a fixed 1 clock delay following the falling edge of horizontal sync. This is the lower byte
of the 10-bit word.
0011 1111_B
BIT
NUMBER
FUNCTION
15 - 10 Not Used
TABLE 15. HORIZONTAL AGC START TIME REGISTER
DESTINATION ADDRESS = 09_H
Write Ignored, Read 0’s.
DESCRIPTION
RESET
STATE
XXXX XX
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