【正文】 op amp39。 The design of microcontrollerbased signal generator Huang Pengyong (Meizhou Bay Vocational Technical College, Putian, Fujian, 351 254) Abstract Waveform generator, a simple function signal generator, a produce a variety of waveforms, such as the triangle wave, sawtooth wave, square wave, sine waveform circuit. Function signal generator circuit experiments and equipment, instruments with a wide range of uses. By the principle of the function generator, as well as structure analysis, can be designed one can transform the triangle wave, sawtooth wave, square wave, sine function waveform generator. Function signal generator signals in industrial production and scientific research to measure the performance and parameters of the ponents, electrical and electronic products index validation, parameter adjustment, and performance appraisal. Most of the monly used signal generator by an analog circuit, this analog signal generator for lowfrequency signal output often requires the RC value, so that not only the parameters of accuracy is difficult to guarantee, but the size and power consumption are large by the digital circuit posed of lowfrequency signal generator, although its performance is good, but larger, more expensive, highprecision, wide amplitude modulation will bee the trend of the digital signal generator. This article describes the 89C52 microcontroller and digital to analog converter DAC0832 to produce the desired signal of the low frequency signal source, the signal amplitude and frequency can be controlled as required. The article briefly describes the structure of principles and use of the DAC0832 digitaltoanalog converter, the 89C52 basic theory and design of circuits a variety of chips. The paper focuses on how to use microcontroller to control the D / A converter to produce the hardware and software programming of the above signals. The signal frequency range is also adjustable as required. The core of the design tasks are: AT89C52 as the D / A converter and DAC0832 devices, circuit simulation software, design hardware drivers written in C, in order to achieve process control to produce sine wave, triangle wave, square wave, three monly used lowfrequency signals. Waveforms and enter any frequency value can be selected via the keyboard. Key words: on AT89C52 function waveform generator DAC0832 square wave, triangle wave, sine wave 1 Introduction SCM is an integrated circuit chip, VLSI technology with data processing capability of the central processing unit CPU random access memory RAM, read only memory ROM, and a variety of I / O port and interrupt system, timers / timer other functions (which may also include a display driver circuit, pulse width modulation circuit, analog multichannel converter, A / D converter and other circuit) integrated into a silicon constitute a small puter system. The waveform generator is a data signal generator, in the debugging of hardware, we often need to add some signal, whether it is normal to observe circuit operation. General signal generator, not only cumbersome, but only made a few simple waveform, can not meet the need. Example, when users want to debug serial munication program, it is necessary on the puter to write a program, and then wire to connect the puter and the user target board, if not normal, do not know that the munication lines have a problem or a problem with the program. E2020 / L waveform generator capability, you can define the serial data. Output logic probe hook, quick and easy to debug. Based on a simple waveform generator of the microcontroller is a mon source, is widely used in the experiment of electronic technology, automatic control system and other scientific fields. At present, the position of simple waveform generator There are many ways, such as type of DDS (Direct2Digital Synthesis) arbitrary waveform generator, using a dedicated signal chip MAX038 AWG. The design stems from the 2020 National Undergraduate Electronic system to contest, through analysis and parison with traditional methods to achieve the multifunction waveform generator. With highperformance singlechip high speed of operation, system integration, strong advantages, the design of this signal generator, digital signal generator than the previous hardware is simple to understand and implement easier, clearer design ide