MT9V112 Datasheet, PDF (29/58 Pages) Micron Technology – SOC VGA DIGITAL IMAGE SENSOR

PRELIMINARY
MT9V112
SOC VGA DIGITAL IMAGE SENSOR
Table 10: Camera Control Register Description (continued)
Bits 7:0
Luma value of the auto exposure target.
R47:2—0x22F – Auto Exposure Speed and Sensitivity Control—Context A (R/W)
Default
0xDF20
Description This register specifies the speed and sensitivity to changes of auto exposure in context A.
Bit 15
Reserved.
Bit 14
Reserved.
Bits 13:12 Reserved.
Bit 11
Reserved.
Bit 10
Reserved.
Bit 9
Reserved.
Bits 8:6
Factor of reduction of the difference between current luma and target luma. In one adjustment auto
exposure advances from current luma to target as follows:
“000”—1/4 way going down, 1/8 going up.
“001”—1/4 way in both directions.
“010”—1/2 way in both directions.
“011”—1/2 way going down, 1/4 going up.
“100”—All the way in both directions (fast adaptation!).
“101”—3/4 way in both directions.
“110”—7/8 way in both directions.
“111”—Reserved. Currently the same as “100”
Bit 5
Reserved
Bits 4:3
Auto exposure luma is updated every N frames, where N is given by this field.
Bits 2:0
Hysteresis control via time-averaged smoothing of luma data. Luma measurements for auto exposure are
time-averaged as follows:
“000”—Auto exposure luma = current luma.
“001”—Auto exposure luma = 1/2 current luma + 1/2 buffered value.
“010”—Auto exposure luma = 1/4 current luma + 3/4 buffered value.
“011”—Auto exposure luma = 1/8 current luma + 7/8 buffered value.
“100”—Auto exposure luma = 1/16 current luma + 15/16 buffered value.
“101”—Auto exposure luma = 1/32 current luma + 31/32 buffered value.
“110”—Auto exposure luma = 1/64 current luma + 63/64 buffered value.
“111”—Auto exposure luma = 1/128 current luma + 127/128 buffered value.
R91:2—0x25B - Flicker Control (R/W)
Default
0x0002
Description Primary Flicker Control Register.
Bit 15
(READ only) 50Hz/60Hz detected.
0: 50Hz detected.
1: 60Hz detected.
Bit 2
Reserved.
Bit 1
When in “manual” flicker mode (R91:2[0] = 1), defines which flicker frequency to avoid.
0: Forces 50Hz detection.
1: Forces 60Hz detection.
Bit 0
0: Auto flicker detection.
1: Manual Mode.
R98:2—0x262 – Auto Exposure Digital Gains Monitor (R/W*)
Default
Description These digital gains are applied within the IFP; they are independent of the imager gains.
Bits 15:8
Post-lens correction digital gain (writable if auto exposure is disabled).
Bits 7:0
Pre-lens correction digital gain (writable if auto exposure is disabled).
09005aef8154a39d/09005aef8175e6cc
MT9V112_2.fm- Rev. A 1/05 EN
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