以单片机为中央控制器，设计一台出租车计价系统。系统中的直流电源由车载电源提供，电源电压为+9V~+24V。行驶里程传感器不需要设计，假设它具有汽车每行使1km提供1000个脉冲信号的特性。显示器可以采用LED数码管或LCD液晶显示模块。

应达到的技术指标：

1、 白天、晚上分别设置不同的里程单价，两位数码显示“X.X”,并用一键控制转换及

显示；

2、 两位数码显示车辆行使的里程数“XX”；

3、 营运起步价为5.00元，当小于3公里按起步价结算，当大于3公里时，按里程单价×里程数结算，并用三位数码显示“XX.X”；

4、 一键控制总价清除及开始计价，即按一下系统开始计价，再按一下时总价被清除（即用按键模拟出租车上的“空车”指示牌功能）。 -Single-chip microcomputer as the central controller, the design of a taxi meter system. System in the DC source is vehicle power supply, power supply voltage of+9 V ~+24 V. No mileage sensor design, assuming it has a car 1km each exercise provides 1000 pulses features. LED digital tube display can be used or LCD display module.

Should meet the technical specifications:

1, daytime, evening set different mileage unit, two digital display "XX", and conversion and with a key control

Display

2, the exercise of two digital display vehicle mileage "XX"

3, the operation starting at 5.00 yuan, while less than 3 km at prices starting at settlement, when more than 3 km, priced according to mileage × mileage settlement, and with three digital display "XX.X"

4, a key control and began to clear the total valuation, that valuation system began clicking, and then click when the total is cleared (ie, simulated with a taxi on the button "empty" sign function).