Acer S2W 3300U Service Manual - Page 29

5.3. Scanner Controller (ASIC & µ P) The scanner controller consists of an embedded CPU,USB controller M5611 and scanner controller. The CPU executes programs in CODE SRAM and does the following jobs: initialization, system selftest, calibration, panel handling, scan handling USB port interface and other signal control. 5.3.1 Features The AP7107u (ASIC) includes the following features: 1. 12 bit CCD data input. Output: 8 bit per gray scale, 1 bit per pixel for binary scanning. 2.Support monochrome CCDs with horizontal optical resolution up to 16384 pixels. 3.Built-in CCD timing generator. This ASIC also provides signals needed for implement external CCD timing generator . 4.Built-in digital offset compensation. 5.Built-in mirror image processing. 6. Built-in digital shading to reduce number of analog parts in scanner circuits. 7. Built-in noise reduction LPF. 8. Built-in Gamma correction function for gray-level/color scanning. 9. Built-in halftone processing for binary image scanning. 10. Provide 6 output pins to control line motor. 10. Host I/O is done by CPU.