ADNS-3090 Datasheet, PDF (35/38 Pages) Pixart Imaging Inc. – High-Performance Optical Mouse Sensor

PixArt Imaging Inc.
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Frame_Period_Min_Bound_Lower
Access: Read/Write
Bit
Field
7
FBm₇
6
FBm₆
Address: 0x1B
Reset Value: 0xAC (before SROM download)
0x7E (after SROM download)
5
4
3
2
FBm₅
FBm₄
FBm₃
FBm₂
1
FBm₁
0
FBm₀
Frame_Period_Min_Bound_Upper
Access: Read/Write
Bit
Field
7
FBm₁₅
6
FBm₁₄
Address: 0x1C
Reset Value: 0x0D (before SROM download)
0x0E (after SROM download)
5
FBm₁₃
4
FBm₁₂
3
FBm₁₁
2
FBm₁₀
1
FBm₉
0
FBm₈
Data Type: 16-bit unsigned integer.
USAGE: This value sets the minimum frame period (the MAXIMUM frame rate) that may be selected by the automatic
frame rate control. Units are clock cycles. The formula is
Frame Rate = Clock Rate / Register value
To read from the registers, read Upper first followed by Lower. To write to the registers, write Lower first, followed by
Upper, then execute a write to the Frame_Period_Max_Bound_Upper and Lower registers. The minimum allowed
write value is 0x7E0E; the maximum is 0xFFFF.
Reading this register will return the most recent value that was written to it. However, the value will take effect only
after a write to the Frame_Period_Max_Bound_Upper and Lower registers. After writing to Frame_Period_Max_
Bound_Upper, wait at least two frame times before writing to Frame_Period_Min_Bound_Upper or Lower again. The
“Busy” bit in the Extended_Config register may be used in lieu of a timer to determine when it is safe to write. See the
Extended_Config register for more details.
In addition, the three bound registers must also follow this rule when set to non-default values:
Frame_Period_Max_Bound ≥ Frame_Period_Min_Bound + Shutter_Max_Bound.
All rights strictly reserved any portion in this paper shall not be reproduced, copied or transformed to any other forms without permission.
PixArt Imaging Inc.
E-mail: [e-mail]
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