关键词：AT89S52单片机；并行通信；LED数码管显示
Abstract
AT89S52 SCM system adopts the control, the whole hardware system consists of A/D and D/A transformation, LED display, keyboard, parallel communication module. This design only completed the microcontroller part of the design development, no design external gathering and control circuit. Because there is no external acquisition circuit, so you can't accomplish specific measurement function, to accomplish specific measurement functions (such as measuring pressure, temperature, humidity) also deserve to various sensors outside of acquisition circuit and the corresponding software. If the match on acquisition circuit and the corresponding software can with the measured results LED digital tube decimal shown, including the A/D and D/A transformation, still can use the button to control for the man-machine dialogue; System set up five buttons, which one is reset button, the rest of the four key, with procedures to control the realization of different functions. Did not design external acquisition circuit because the external acquisition circuit design is the function of the system is more onefold, inconvenient system function of external expansion. This system can achieve the microcontroller and PC parallel communication and programming to download, software design of the clock display.
Key words: AT89S52 SCM; Parallel communication; LED digital tube display
