4 Based on monolithic integrated circuit's data acquisition system
     Based on monolithic integrated circuit's data acquisition system hardware circuit including monolithic integrated circuit modules and so on control core, monitoring module, A/D sampling, demonstration actuation, data storage, data transmission. Shown in Figure 1 for the data acquisition system composition diagram.
 Figure 4.1  Data acquisition system composition diagram
4.1 Monolithic integrated circuit control module
The this data acquisition system's monolithic integrated circuit control module selects AT89S52. AT89S52 has 40 pins, 8 KB the Flash internal program memory, 1 full-duplex serial passes unguardedly, built-in watch-dog (WDT) electric circuit.
4.2 Monitoring module
In the observation system has the power source to open breaks, the transient voltage not stably and so on factors, causes the system to halt, the bit drop-out, the movement not stably and so on breakdowns. In order to realize the system safety reliable, stable, the real-time movement, must join the monitoring module in the observation system. System's monitoring module uses x25045, this component has functions and so on voltage monitoring, watch-dog timer and E2PROM. May establish contacts directly with the micro controller's I/O port.
4.3 A/D sampling module
The A/D sampling module uses TLC1543. TLC1543 is TI Corporation uses the SPI technology the modulus switch, has the input channel many, high speed, the high resolution, the high performance-to-price ratio, easy and characteristics and so on monolithic integrated circuit connection.the TLC1543 control carries CS, I/O CLOCK, ADDRESS and data out-port DATAOUT follows the serial peripheral device connection SPI agreement. Although 51 series monolithic integrated circuit not built-in SPI connection, but only need then realize the correspondence through the software simulation SPI agreement. TLC1543 and between microprocessor's serial interface may through a 4 connection high speed transmission data.
4.4 Demonstration actuation module
The system demonstrated that the actuation module uses PS7219. PS7219 is one kind of high performance-to-price ratio many LED demonstration supervisor, uses synchronized serial peripheral device connection (SPI), may be connected with any monolithic integrated circuit, and may simultaneously actuate 8 LED.
4.5 Serial communication interface circuit
In the industry observation system, gathers the scene simulation quantity, the switch quantity commonly used in 51 series monolithic integrated circuits, but PC machine uses in monitoring the entire control scene. This both's data transmission or constitutes the localized network, multiuser systematic and the distributional control system uses the serial communication, PC machine is generally the main engine, the monolithic integrated circuit for from machine. This system data transmission uses the asynchronous serial communication, uses Maxim Corporation's model serial communication connection component MAX232ECP to realize the data transmission.
4.6 Data storage module
To realize the system data fixed time to gather and according to the date preservation data, expands piece of real-time clock calendar component SD2001E. This component has the I2C bus interface, the built-in real-time clock needs electric circuits and so on battery, crystal oscillator, power source management. When system power failure may guarantee the clock normal operation. SD2001E does not need the periphery part, then constitutes the high accuracy real-time clock and has 256 KB non-volatility SRAM data storage electric circuit.
SD2001E uses 24 pin DIP seal. SD2001E principal characteristic: Year, month, Japan, week, pides, the second BCD code input/output: I2C bus interface (including real-time clock part and SRAM part); Automatic calendar to 2099 (including leap year automatic conversion function); The built-in crystal oscillator, before the leaving the plant, to the clock calibration, had guaranteed that the precision for ±4×10-6, namely the clock year error is smaller than 2 min; The low power loss, the typical value is 1.0μA (VDD=3.5 V); The working voltage is 3.0 V~5.5 V; May establish two groups alarm clocks to output and 1 Hz~32 768 Hz square-wave signal outputs; May establish each minute fixed interrupt output or the designation frequency fixing interrupt output; Built-in charging circuit and rechargeable battery, power source management electric circuit as well as voltage-stabilizer circuit and battery power failure examination electric circuit; Built-in 256 KB non-volatility SRAM, it scratches writes the number of times is 10,000,000,000 times, and writes the time delay without the interior. 单片机的数据采集系统英文文献和中文翻译(2):http://www.youerw.com/fanyi/lunwen_32092.html