lm9831 National Semiconductor Corporation, lm9831 Datasheet - Page 12

• Manufacturer Part Number: lm9831
• Description: 42-bit Color, 1200dpi Usb Image Scanner
• Manufacturer: National Semiconductor Corporation

Address
HORIZONTAL RESOLUTION AND DATAMODE SETTINGS
RESERVED
SENSOR CONFIGURATION
09
0A
0B
Horizontal DPI Divider
This register determines the horizontal
resolution of the scan.
Scan resolution = Optical resolution divided
by the Horizontal_DPI_Divider.
Pixel Packing
This register determines how many bits in
each byte of data are transmitted to the host
when DataMode = 0
DataMode
When DataMode = 0, the pixel data is fully
processed, going through the Offset,
Shading, Horizontal DPI Adjust, Gamma,
and Pixel Packing blocks.
When DataMode = 1, 14 bit data is extracted
following the Shading Multiplier stage.
Gamma and any other post processing must
be done by the host.
Reserved
Input Signal Polarity
CDS On/Off
Standard/Even-Odd Sensor
CIS TR1 Timing Mode
Fake Optical Black Pixels
(for Dyna-type CIS sensors)
Function
D
7
0 0 0 0 0 0 0 0 Write 00 to this register
D
6
D
0
1
0
1
5
D
4
0 0
0 1
1 0
1 1
0 0
0 1
1 0
1 1
12
D
3
D
0 0 0 ÷1
0 0 1 ÷1.5
0 1 0 ÷2
0 1 1 ÷3
1 0 0 ÷4
1 0 1 ÷6
1 1 0 ÷8
1 1 1 ÷12
0
1
2
D
0
1
1
D
0
0 Negative (Most CCD Sensors and Toshiba CIS)
1 Positive (Most CIS Sensors)
1 bit/pixel (1 bit grayscale/3 bit color)
2 bits/pixel (2 bit grayscale/6 bit color)
4 bits/pixel (4 bit grayscale/12 bit color)
8 bits/pixel (8 bit grayscale/24 bit color)
1, 2, 4, or 8 bit image data,
as determined by the Pixel Size setting.
14 bit image data - sent in 2 bytes, MSB first:
First Byte: 13 12 11 10 09 08 07 06
Second Byte: 05 04 03 02 01 00 XX XX
(XX: bits set to 0)
CDS Off
CDS On
Standard (1 pixels per Ø period)
Even/Odd (2 pixels per Ø period)
Off - use standard CCD Timing
CIS TR1 Timing Mode 1:
TR1 pulse = exactly one Ø clock,
starting at rising edge of Ø1
CIS TR1 Timing Mode 2:
TR1 pulse = exactly one Ø clock,
TR1 centered around Ø1 high.
N/A
Off: Normal operation
On: RS pulse held high for entire Optical Black period
Value
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