The Design Of The LED Information Display System

LED display is use light-emitting diode dot matrix module or flat-display screen consisting of pixel modules.Because it has the advantages of a high rate of luminous,long service life,configuration flexibility,rich colors,a strong ability to adapt the environment indoor and outdoor and so on. So it has been widely used in foreign countries.The dot matric display control panel calculates the dot-matrix code of display graphics.By controlling the date and pulse pin,input the data of some line, and then strobethe line. And by using a simple digital circuit peripheral to drive 128*32 dot matrix LED display ,LED display will get the dot-matrix disply of the line. After line-by-line scanning it will obtabe the whone screen disple.In order to solve the cornmon dot-matrix disple interferenced,delayed and obvious jitter when the display screen is slightly latger,we discard many chips in the original circuit and use the dot matris display based on CPLD .It simplfies and integrates many peripheral circuits in system successfully,and improve the reliability and stability of the display board, and is useful for the circuit testing and maintenance . By improving scheme our display board in achieving the original function has greatly improved the performance ,and solve the peoblem of jitter successfully.In data transm ission we use enhanced SCMits own styong function ,through the serial port RS232 communicating with the suprior mochine .According to the chinese characters inner code accepted by the serial port inquire the Chinese characters display dot matrix storehouse solidified in the rom,and form display port inquire the chinese characters display dot matrix storehouse solidified in ROM,and form display dot mabix code.In the RAM of LED diaplay control panel establish a diaplay buffer area related with LED display, and then store the dot matrix code of display Chinese characters in this buffer area. LED diaplay control panel will move the data in diaplay buffer area to the diaplay lock regidter of dot matrix diaplay in the serial moving manner continually,and accomplsh diaplay dynamic line scanning by the choice of relative line selected switch.In order to reduce the number of pins and easy to package,LED dot-matrix diaplay LED.Computer through the bus operational control achieves esch LED diaplay brighe and dark control opersttion in esch LED dot matrix diaplay modules,thus achieve LEDdiaplay Chinese characters or graphics diaplaycontrol operation.It can easily achieve the data transmission witch PC and peripheral strage devices,and facilitate to change variously display contents with the use of software,In the whole design process,it has been optimized from hard ware to software,and achieves the variety of screen diaplay successfully.So all indicators have reschde pre-design requiremens basically.