gl845 Genesys Logic, gl845 Datasheet - Page 92

• Manufacturer Part Number: gl845
• Description: High Speed Usb 2.0 2-in-1 Scanner Controller With Adf
• Manufacturer: Genesys Logic

mode. The baud rate can be programmed to 2400,4800, 9600 and 19200 bps by S/W.
36 Supports EEPROM (93C46) Interface
GL845 supports EEPROM interface via internal logic circuitry. Programmers need to set the EPROMSEL
control bit to logic ‘1’. GPIO1 controls SK of external EEPROM, GPIO2 controls DI/DO of EEPROM and
GPIO17 controls CS of external EEPROM under EEPROM mode.
37 Embedded RISC CPU for Scanning, Run-in and Diagnostic Tests
GL845 embeds a powerful RISC CPU. It has timers, counters and interrupt ports. Designers can use the
embedded CPU to do the run-in, diagnostic tests and anything he wants to do.
38 Supports External 24Kbytes flash ROM or Internal 24Kbyte mask ROM
Designers can use 24K bytes embedded mask ROM or external flash ROM. Firmware can be downloaded to
flash ROM directly by PC S/W. It provides a flexible development environment to design the firmware.
39 “True gray” with R,G and B weightings
Designers can obtain the “true gray” image data by enabling “true gray” function. Image data is generated by
R,G and B outputs and multiplied by weightings.
Formula of true gray value = R*(TRUER [7:0]) + G*(TRUEG [7:0]) + B*(TRUEB [7:0])
40 Lossless Data Compression
GL845 use Huffman coding method to implement the lossless data compression.
41 Lines Packing for Stagger CCD or R/G/B Line Differences
GL845 packs R, G and B lines together for CCD sensors by hardware. And it also packs the same color lines
of stagger CCD together.
42 Fine CDS Sampling Adjustment
Designers can fine-tune the CDS sampling position to avoid the digital noise influence (8.33ns adjustment).
The image noise may come from the digital noise of PCB.
43 Wall-Hitting Protection
Designers can use table five of motor moving to protect the wall hitting. The LONGCURV control bit has to
be set to logic ‘1’ to enable the long-curve function. The first several steps are used to decelerate the carriage
moving; the other slower steps are focused on touching the home sensor.
Due to the special table five, designers can replace the photo-sensor by simple, cheaper mechanical-type sensors.
44 Motor Driver IC Setting
Designers add pull up/pull down resistors on MTR_SEL0~2 will indicate ASIC to generate the timing of
specified motor driver IC.
Motor type select : CCD_TGB
When designers select MTR_SEL0~2 to “111”, MT_PH0~7 will output phase table which is stored in internal
©2000-2007 Genesys Logic Inc. - All rights reserved.
GL845 High Speed USB2.0 2-in-1 Scanner Controller With ADF
CCD_TGG
CCD_CK4X
MTR_SEL2
MTR_SEL1
MTR_SEL0
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