Study On The Embedded High Resolution Video Graphics Array Display System

The embedded high resolution Video Graphics Array display system is a kind of portable Video Graphics Array display device. It can show and control the VGA image without using computer or VGA display card. The mainly application of the system is to show the advertisements or the attention information in public place such as the super market, the station or the air station. And it can also be used in the workshop to display the operating information of the production or in the daily life as a multimedia electronic calendar system. The display of three different resolutions of images 1024*768(XGA), 800*600(SVGA) and 640*480(VGA) has been designed and realized.The order structure of software and hardware of the whole system has been designed ,while is based on the study of the theory about the VGA display system. The store of multimedia data, the decoding of the JPEG image, the display of the Chinese characters, the output of the aural signal and the generation of the VGA and display buffer read sequence have been implemented. And the long-range control of system can be realized by the Ethernet interface and the serial interface. Major work of this thesis:1. Based on the study of the theory about the VGA display system, detailed project has been put forward.2. All units of the embedded VGA display system have been designed .A method of using CPLD to generate the VGA display time sequence has been designed, refer to the time parameters of the VGA standard sequence. The VGA analog signal has been generated by using high speed analog to digital chip ADV7120. The data transmission and the control of the whole system have been implemented by using ARM or high speed DSP as processor.3. One of the high speed one dimension IDCT algorithms has been adopted. Only 29 times of multiplication and 11 times of addition are needed in the one dimension IDCT transformation of 8 bits, which improved the decode speed of the JPEG and further more, the real-time performance.4. The embedded software and the computer software of the VGA display system have been designed. The read-write software interface of the EPP and Ethernet interface has been designed to transmit the data and the control commands.The accomplishment of the study is the embedded high resolution VGA display board. Its display effect and the main parameters reached the standard of using require.