【正文】 (2) clocked into the WREN instruction。(3) to send the 8byte address。5, the display code converter module: AD value of the binary system is converted into BCD code, BCD code converted to separate BCD code used to achieve separation, BCD code to convert digital display code in order to send the display, it is the display processing program The advance team.6 SCR zero power adjustment speed control module: used to achieve singlechip control of motor speed.In addition to the above functions, the system also has a watchdog function and work status display.Dynamic display and key scan processing time have high requirements, so the timer interrupt service routine. T1 Timer 0 (T0), the two functions. The dynamic display in a moment, only to a word line is the gating state, namely, the mon cathode is low, the corresponding bit of the field line output you want to display the field code of the character. Others the word line is still in limbo, not shown. Also in the next instantaneous display only the next LED, such a cycle for each LED. Although these characters are displayed in a variety of instantaneous rotation, but due to the residual effect of the human visual to see is each display character. The 1ms initial value loaded into the timer, then the content of the program counter (breakpoint address) onto the stack protected, then the corresponding T0 timer interrupt vector to load the program counter PC, and the program turned to T0 interrupt vector address 000BH execute the interrupt service routine.The X5045 chip poweron reset, voltage monitor, watchdog timer and EEPROM data storage four functions on the set with the multipurpose chip.1, read timing(1) CS low to select the chip。[2] According to the algorithm flowchart: draw the block diagram of algorithms and problemsolving steps and gradually, in order to reduce the risk of error.[3] to write the program: the selection of the appropriate mand to line up according to the block diagram of the algorithms and steps to constitute an organic whole, namely the program.The program data is an ideal method is the structured programming method. Structured programming control structure class program to use to make the appropriate restrictions, in particular, is to limit the use of steering statements (or instructions) to control the plexity of the program, and strive to procedures on the below order and execution processes consistent , make the program easy to read and easy to understand, reduce logic errors and easy to modify, and debug. According to the system control tasks, the software design of the system by the main program, initialization procedures, display of subroutine, data acquisition subroutine, the interrupt subroutine, and delay procedures.To be able to achieve the above functions, after careful analysis and sorting, and the overall function of refinement, distribution, system program is divided into the following main modules:1, the initialization module: This module on the stack, timer, counter, interrupt, and special function registers an assignment, the register is cleared, and counter / timer initial value storage.2, the key operation module: This module in the system, a power after the start of the keyboard scan, once detected, a key is in the appropriate moment, will turn to perform the corresponding handler disposed to return to the main program.3, A / D conversion module: MAX18739。 and in the zero pulse signal. (2) the zerocrossing pulse signal must be controlled by a singlechip output control information control. In order to control the thyristor zero trigger pulse number. These two problems are solved by software and hardware to finishProgram design is a plex task, in order to make plicated orderly, it is necessary to have the appropriate steps and methods. The steps can be summarized as the following three points: the sensor generates a signal in the analog to digital conversion prior to conditioning, including the gain and filtering, this will obviously increase the cost.The integral type A/D converter: such as: ICL7135, ICL7109, ICL1549, MC14433 etc.. The integral type ADC is also known as dual slope or the slope ADC, is used widely in the class of converter. Its basic principle is through the two points will be the input analog voltage into its average value is proportional to the time interval. At the same time, in this time interval counter use when the clock pulses are counted, so as to realize A/D conversion. The integral type ADC two integral time is utilized in conjunction with a clock generator and a counter to determine, thus the obtained expression and clock frequency independent, its conversion precision depends only on the reference voltage VR. In addition, due to the integrator input end, so the AC noise has strong inhibiting ability. If the integrator timing integration time and frequency signal of the integer, the frequency error caused by the noise is reduced to a minimum, and effectively restrain the power frequency interference. This type of ADC is mainly used in low speed, precision measurement and other fields, such as digital voltage meter. Its advantages are: high resolution, up to22。 and other than ADC, power consumption is quite low。s 8051and 8751can be used, here choose ATMENL production AT89CXX series mcu. AT89CXX has two advantages: first, sheet memory storage device with flash memory, so that the writing program more convenient。s weight is converted into known weight of objects with certain functional relationship between ( generally proportional to the relationship of signal ( voltage ) or current ). The signals are amplified by the amplifying circuit, the filter and then by a / D ( A/D ) for the conversion of digital signals, and then sent to the micr