Research Of The Digital Duplicator Based On DSP And FPGA

This topic comes from the digital duplicator project of Shenzhen Eonver Co., Ltd.Aiming at the problems of the bad purchasing channel and the limited quality of the image processed by the digital duplicator with special image processing chip, this paper presents a digital duplicator solution based on DSP and FPGA. This paper uses DSP instead of special image processing chip and improves the quality of the image only by improving the image processing method but not changing the hardware. The FPGA makes it easy to control motors, CIS and so on.A control method of SVPWM with speed-closed loop and current-closed loop is used on timing of three-phase brushless DC motor. This method reduces torque ripple and makes an accurate speed.An optimum position controlling strategy is used on controlling the position of the stepping motor. With this strategy, the step motor has a steady start-up and accurate steps, The stepping motor can come to the destination in less time.This paper analyzes and compares the image smoothing methods, and then determines to use the median filter to smooth image as it can reduce interfere and keep the image with high definition.Digital halftoning methods based on amplitude modulation (AM) and frequence modulation (FM) are introduced in this paper. This paper presents improved strategies to digital halftoning arithmetic based on error diffusion. The improved strategies use serpentine scanning method, threshold choosing with median method and Stucki filter arithmetic. The improved strategies make the image exquisite and distinct and have no moire fringe.This paper uses CY7C68013 which is a USB2.0 functional chip describing the device as a composite device of a printer and a scanner. It makes the digital duplicator has the functions of the printer and the scanner.The digital duplicator in this paper breaks the janpanese monopoly of the core technology on digital duplicator.