外文翻译--基于at89c51单片机的led显示控制系统-单片机(编辑修改稿)

外文翻译--基于at89c51单片机的led显示控制系统-单片机(编辑修改稿)内容摘要：

ss of color, and video display can not only show exercise, clear and fullcolor images, but also show television and puter signals. Although there are some differences between the three, but the most basic principles are similar, II. System Overall Structure Design Single Chip Microputer (SCM) models were selected according to the target, function, reliability, cost, accuracy and speed of the control system. According to the actual situation of the subject, the choice of SCM models mainly considered from the following two aspects: First, SCM has strong antiinterference ability。 Second, SCM has a higher costeffective. Due to MCS51 is widely used in China, has more information and can patible with the more peripheral chips too, in particular, ATMEL Corporation, introduced a new generation microcontroller in 2020, that is 89S series, and its typical products with high performance and low cost microcontroller is AT89C52. AT89C52 is a low voltage, highperformance CMOS 8bit microcontroller, the chip includes 8 KB readonly program memory (PEROM) which erase can be repeated, 256byte random access data memory (RAM), devices adopt highdensity nonvolatile memory technology to produce, patible with the standard MCS51 instruction set and the 8052 products, while the chip builtin generalpurpose 8bit central processing (CPU). Flash storage unit, can be applied to 7 the more plex control applications. The system was realized by the circuitry which is made up of AT89C52 chip, Clock circuit, reset circuit, column scan driver circuit, line drive circuit and the six 32 32 LED dot matrix, the overall structure of LED characters display is shown in . A display unit is posed of dot matrix and two 74HC154. Line data signal is divided into two parts, which is given by the two 8255A respectively, but the 8255A data are from the P0 port the master controller AT89C52. The column scanning signal of each character was given by the two 74HC154, the 74HC154 12 pieces and was divided into six groups. The input signal of 74HC154 was given by the ~ of AT89C52. External data memory 6264 connected with the AT89C52 the P0 port. III. SYSTEM HARDWARE CIRCUIT DESIGN A. Circuit Design of MCU Control System The size of Chinese characters is 32 32, but microcontroller has 32 I/O port, and can’t meet design requirements, so the I/O port must expand, the data port expansion was implemented by two 8255A. The data port expansion is shown in , 74HC373 is the address latch, and latch low eight address, the low eight address signals of 6264 provided by it, but the high eight address signals of 6264 provided by ~, Internal port of 8255A was chosen by A0 and A1. 74HC139 is 24 decoder, whose input signals are provided by and of SCM, and provided strobe for the external I / O devices, because the system has more than one external device, make sure that they can not be gated, so that their addresses is the only and do not repeat. The clock circuit of AT89C52 posed of 18, 19feet from the clock side (XTALI and XTAL2), and 12MHz crystal, capacitor C1 and C2. B The Circuit Design of Display Memory Unit The size of Chinese characters is 3232 in the design, each character posed of four parts。