Development Of Multi-function Experiment Board Based On AT89C52

With the development of electronic technology, the microcontroller in the industrialcontrol, smart instrumentation, peripheral control, household appliances, robots have madeextensive use. Thus, in schools and factories in more and more people learn microcontroller.To help them learn better, especially designed for this experiment, a multi-functional board.The test board can be used as their experimental circuit boards. To help users better learnmicrocontroller programming to their own hands, especially a multi-user experiment designedboard. The microcontroller board for fans of those in use on the machine programming. Thisexperimental activities for the development of high value.For this experiment board requirements are: relatively low price, very good to learn thecontents of the classroom and experiment together. Based on the above requirements, thedesign of the circuit moderators have the following components: DC power supply,microcontroller minimum system, reset circuit, keyboard and LED display interface circuit,A/D conversion interface circuits, D/A converter interface circuits, RS-232Interface circuit.The test board consists of the following components:1, power supply.2, the smallestsingle chip system.3, the reset circuit.4, keyboard and LED display interface circuit5, A/Dconversion interface circuit.6, D/A converter interface circuits.7, RS-232interface circuit.The experiment plate using ATMEL’s microcontroller AT89C52, D/A converter chipDAC0832, A/D converter chip we use the ADC0809, the parallel interface chip8255A, datamemory by6264.We designed this versatile experimental board the need to achieve A/D conversion, D/Aconversion, and computer communication interface, keypad and LED display functions. Atthe same time can be achieved by programming the signal generator, oscilloscope, counterand other functions. In addition, in order to better demonstrate program design, you need towrite can be directly coupled to the control of light-emitting diodes.The experiment board to the main function is as follows:(1) A/D conversionIt can be analog input voltage value is converted to digital form, and through the LEDdigital display tube display analog voltage values. The value of the voltage requiredbetween-5V-+5V. (2) D/A conversionIt is through D/A converters produce a given value of the voltage, the voltage value inthe LED digital display tube display. The value of the voltage required between-5V-+5V.(3) Intelligent Signal GeneratorThe board can generate sine, triangle wave, sawtooth, square wave, exponential integralwave, the index differential wave, which frequency, waveform can be configured keyboard,and the frequency by using decimal LED digital display. Where the amplitude range of-5V-+5V between.(4) oscilloscopeThe board not only as a low-speed digital storage oscilloscope, it is by an external analogsignals into digital signals and stored, and through the RS-232interface data to the computer,and then the analog signal from the computer display, in order to achieve Analog signalstorage. At the same time it also displayed on the computer directly to analog signals.(5) CounterThe board can also count external pulses, through an external LED display the totalnumber of pulses. The maximum count is10,000, counting to10,000after the reset and thenre-count.(6) light is blinking functionThe circuit board can be programmed light cycle display. Similarly, we can also realizewe can be programmed to display any form of light, thus greatly facilitate our demo.(7) and PC-communicationThe circuit board provides RS-232communication interface, so that we cancommunicate with the PC machine. We can be programmed to receive the circuit board to thePC, the data displayed on the LED above.In addition, the board also provides a self-test function to detect RAM, if properlydisplayed through the LED display GOOD, if an error is displayed BAD.Using this experimental board we can set up the following experiment:(1) light is blinking(2) A/D conversion(3) D/A Converter(4) generating sine wave, triangle wave, sawtooth, square wave, exponential integralwave, the index differential wave(5) to an external signal storage and display by computer(6) count of external signal (7) RAM detection(8) communicates with the PC and displays the received data...