ch5001a ETC-unknow, ch5001a Datasheet - Page 29

• Manufacturer Part Number: ch5001a
• Description: Cmos Color Digital Video Camera
• Manufacturer: ETC-unknow

CHRONTEL
Auto-Shutter Black Count Threshold
Bits 2-0 of register ASBC determine the black threshold used by the auto-shutter algorithm. The value used is
8*ASBT+3. Bits 7-3 of register ASBC determine the number of pixels below the ASBT level. When the number of
pixels is less than this value, the autoshutter algorithm will adjust the black level downwards. When the number of
pixels is greater than this value, the black level will be adjusted upwards.
The number of pixels above the white level is compared to the ASWC value to determine the direction that the
shutter value should be changed.
Electronic Shutter Length Extended Value
The ESLE register, combined with the ESLH and ESLL registers, determine the length of the electronic shutter.
201-0000-032 Rev 3.0, 6/2/99
Table 13. Autoshutter Algorithm Input
Auto-Shutter White Count Threshold
BIT:
SYMBOL:
TYPE:
DEFAULT:
BIT:
SYMBOL:
TYPE:
DEFAULT:
BIT:
SYMBOL:
TYPE:
DEFAULT:
ASME
0
0
1
ASWC7
ASBC4
R/W
R/W
7
7
7
1
1
ASCSC
0
1
x
ASWC6
ASBC3
R/W
R/W
6
6
6
1
0
‘Y[7:0]’ output of color space conversion
A/D output
MAX (A/D, Y[7:0])
ASWC5
ASBC2
Input to Autoshutter Algorithm
R/W
R/W
5
1
5
5
0
ASWC4
ASBC1
ESLE4
R/W
R/W
R/W
4
1
4
0
4
0
ASWC3
ASBC0
ESLE3
R/W
R/W
R/W
3
1
3
0
3
0
ASWC2
ASBT2
ESLE2
R/W
R/W
R/W
2
0
2
0
2
0
Symbol:ASWC
Address:20h
Bits:8
Symbol: ESLE
Address:21h
Bits:5
Address:1Fh
Bits:8
Symbol:ASBC
ASBT1
ASWC1
ESLE1
R/W
R/W
R/W
1
0
1
0
1
0
CH5001A
ASBT0
ASWC0
ESLE0
R/W
R/W
R/W
0
1
0
0
0
0
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