This gathering system design realizes the following function using SD2001E:
(1) Real-time clock calendar. SD2001E may provide the high accuracy the clock and the calendar function, has timing data gathering, the output control, the data storage satisfiedly as well as fixed time reports to the police and so on function embedded system needs, simultaneously may also provide the time as well as the date demonstration function for the system.
(2) Data storage. Using SD2001E internal 32 KB, scratches writes the number is 10,000,000,000 time high performance NVRAM, does not need to consider that the memory scratches writes the life and the data storage reliable question. Therefore, SD2001E was these needs the frequent read-write data the application to provide the solution.
(3) Fixed time outputs. When the system needs fixed time to output take the minute as the Fundamental unit (for example gathering cycle with multi-channel data acquisitions which, tour examination system decides and so on), may SD2001E the condition register's INT1ME position " 1 ", the INT1FE position " 0 ", take choose as each minute border interrupt output or INT1ME, INT1FE simultaneously sets " 1 " the choice for each minute fixed interrupt output. Through monolithic integrated circuit's counter or the interrupt number of times software counting's method, may obtain take the minute as unit's random time output. SD2001E and AT89S52 monolithic integrated circuit's hardware junction circuit as shown in Figure 2. Because AT89S52 does not have the I2C main line, therefore uses P2.0 and the P2.1 connection line simulates the I2C main line. SD2001E internal SRAM I2C bus interface SDAE and SDA are parallel, SCLE and SCL are parallel.
 Figure 4.2 SD2001E and AT89S52 connection diagram
基于单片机的数据采集系统
1.单片机简介
单片机是指一个集成在一块芯片上的完整计算机系统。尽管他的大部分功能集成在一块小芯片上，但是它具有一个完整计算机所需要的大部分部件：CPU、内存、内部和外部总线系统，目前大部分还会具有外存。同时集成诸如通讯接口、定时器，实时时钟等外围设备。而现在最强大的单片机系统甚至可以将声音、图像、网络、复杂的输入输出系统集成在一块芯片上。
2.传感器
随着科学技术的迅猛发展，非物理量的测试与控制技术，已越来越广泛地应用于航天、航空、交通运输、冶金、机械制造、石化、轻工、技术监督与测试等技术领域，而且也正逐步引入人们的日常生活中去。可以说，测试技术与自动控制水平的高低，是衡量一个国家科学技术现代化程度的重要标志。传感器技术是实现测试与自动控制的重要环节，在测试系统中，被作为一次仪表定位，其主要特征是能准确传递和检测出某一形态的信息，并将其转换成另一形态的信息。
    具体地说传感器是指那些对被测对象的某一确定的信息具有感受（或响应）与检出功能，并使之按照一定规律转换成与之对应的可输出信号的元器件或装置。如果没有传感器对被测的原始信息进行准确可靠的捕获和转换，一切准确的测试与控制都将无法实现，即使最现代化的电子计算机，没有准确的信息（或转换可靠的数据），不失真的输入，也将无法充分发挥其应有的作用 单片机的数据采集系统英文文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_32092.html