统计一组数中的负数个数，三种方法，DUT计算机原理作业5_3-Statistics in a group of several negative number, three methods, DUT computer operating principle 5_3

从串口接收车检器接收机数据，并转换成电平信号-Level signal and convert the device-under-test (DUT) receiver data from the serial port to receive car

它利用了STC11系列单片机能同时进行输入输出的特点，借助温度传感器检测来向被测设备（DUT）输出一个激励信号，同时采集从被测设备返回的响应信号来进行处理分析通常，被测设备(DUT)包含各种不同的功能，需要通过外围的测试硬件来进行检验-Advantage STC11 Series MCU both input and output characteristics, with the temperature sensor detects a stimulus to the device under