gl848 Genesys Logic, gl848 Datasheet - Page 81

• Manufacturer Part Number: gl848
• Description: High Speed Usb 2.0 2-in-1 Scanner Controller With Fast Adf & Bus Power
• Manufacturer: Genesys Logic

GL848 High Speed USB2.0 2-in-1 Scanner Controller With Fast ADF
Scanning Window
Document Sheet
ADF
Document
Sensor
Sensor
PSTFED
When document sheet keeps moving forward, after sensing the absent of document by ADF sensor, scanning
process will be terminated after PSTFED scanning lines.
33 Supports RS232 Interface
GL848 supports RS232 interface via internal logic circuitry. Programmers need to set the RS232SEL control
bit to logic ‘1’. GPIO6 transmits the data of RS232 and GPIO28 receives the data of RS232 under RS232
mode. The baud rate can be programmed to 2400,4800, 9600 and 19200 bps by S/W.
34 Supports EEPROM (93C46) Interface
GL848 supports EEPROM interface via internal firmware. GPIO6 controls SK of external EEPROM, GPIO5
controls DI/DO of EEPROM and GPIO7 controls CS of external EEPROM.
36 “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])
38 Lines Packing for Stagger CCD or R/G/B Line Differences
GL848 packs R, G and B lines together for CCD sensors by hardware. And it also packs the same color lines
of stagger CCD together.
39 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.
40 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.
©2000-2007 Genesys Logic Inc. - All rights reserved.
Page 81