新疆大学课程设计报告所属院系：电气工程学院专业：电气工程及其自动化课程名称：电子技术基础B设计题目：出租车自动计费器班级：电气#####班学生姓名：要要学生学号：@@@@@@指导老师: 常翠宁刘兵完成日期：2013. 1. 4出租车自动计费器一、总体方案的选择1.拟定系统方案框图：方案一：汽车在行驶时，里程传感器将里程数转换成与之成正比的脉冲个数，然后由计数译码电路变成收费金额。
里程传感器由磁铁和干簧管组成，磁铁置于变速器涡轮上，每行驶100米，磁铁与干簧管重合一次，即输出一个脉冲信号，则10个脉冲/公里（设为P3）。
里程单价（设2.1元/公里）可由两位（B2=2、B1=1）BCD拨码开关设置，经比例乘法器（如J 690）后将里程计费变换成脉冲数P1=P3(1B2+0.1B1)。
由于P3=10，则P1为21个脉冲，即脉冲当量为0.1元/脉冲。
同理，等车计费也可以转换成脉冲当量，这需要由脉冲发生器产生10个脉冲/10分钟（设为P4），如果等车单价为0.6元/10分钟（置B4=0、B3=6），经比例乘法器后将等车计费变换成脉冲数P2=P4(0B4+0.1B3)。
由于P4=10，则P2为6个脉冲，即得到相同的脉冲当量为0.1元/脉冲。
同理，起步价（设3元）也可以转换成脉冲数（P0= 单价/当量=5/0.1=50个脉冲)或者将P0作为计数器的预置信号（框图所示）。
最后行车费用转换成脉冲总数P=P0+P1+P2，其结果用译码显示器显示。
图1：出租车自动计费器方案一框图脉冲，行程里程及起步电路则是60毫秒/脉冲。
而等候电路为6秒/脉冲。
实现此电路我用555多谐振荡器构成。
为了减少实验测量时间，我把脉冲周期都缩小了1000倍，即0.06毫秒/脉冲和6毫秒/脉冲。
设计电路图及仿真波形图如下：图3：0.06毫秒555多谐振荡脉冲电路图4：0.06毫秒脉冲波形图图5：6毫秒555多谐振荡脉冲电路图6：6毫秒脉冲波形图2.里程计数及计价电路（1）行车里程计费行车里程计费的电路将汽车行驶的里程数转换成与之成正比的脉冲个数，然后由计数译码电路变成收费金额，在出租车转轴上加装传感器，以便获得“行驶里程信号”。
若每前进10米发一个脉冲到一公里，则输出100个脉冲，需要有一个脉冲发生器产生与等候时间成正比的脉冲信号，然后选用BCD码乘法器将里程脉冲数乘以每公里的单价比例系数，由于器件有限，所以此部分通过预算直接将计费电路的里程计费变换为脉冲个数。
由于单价为1.5元/公里，则可以用150脉冲代替，，即一个脉冲当量为0.01元/脉冲。
0.06豪秒脉冲驱动150进制计数器表示图7：0.06豪秒脉冲驱动150进制计数器（2）等候里程计费与里程计费一样，需要把等候时间变成脉冲个数，且每个脉冲所表示的金额（当量）应与里程计费等值，即0.01元/脉冲。
也需要有一个脉冲发生器产生与等候时间成正比的脉冲信号。
此过程计费为1元/10分钟，即0.1元/分钟，所以可以用10个脉冲代替起价计费。
所以等候时间用10进制计数器表示。
如下图8所示：（3）起步价计费此电路也按当量将起步价转换成脉冲个数，由于起步价为6元，所以用600个脉冲代替，即用600进制计数器表示。
如下图9所示：图8：6豪秒脉冲驱动10进制计数器图9：0.06豪秒脉冲驱动600进制计数器3.总的费用显示电路设计：总的费用显示用0000—9999一万进制表示，最高费用为999.9元。
经测试仿真满足要求，其电路如下图所示：图10：总的费用显示电路三、总电路图图11：总电路图表1 元器件明细表四、仿真与电路调试1.利用软件仿真利用EDA软件MultiSim10对所需设计的电路进行仿真，仿真结果如下：（1）等待计费仿真：图12：等待计费仿真图（2）起步计费仿真:图13：起步计费仿真（3）超过起步价行车计费图14：超过起步价行车计费2.实验室调试在利用MultiSim10实现仿真后，我和组员到实验室进行调试，在调试过程中发现软件与实际接线还是有区别的，比如：在软件上74LS192的4号管脚必须接高电平芯片才能工作，而在实验室做调试是，4号管脚悬空即可，无需接高电平。
还有在调试时发现150进制计数器在从000计数到149时不能自动清零，经过同组员的共同检查和讨论，发现74LS192的14号管脚清零端没有接高电平，在接上高电平后计数器才正常工作，继而完成调试！在这次调试过程中我发现，理论和实际还是有区别的，只有掌握扎实的理论值，才能在实践中善于发现问题和解决问题。
这次调试提高了我理论联系实际，善于思考和敢于实践的能力！六、参考文献[1] 康华光《电子技术基础》（第五版），高等教育出版社出版[2] 毕满清《电子技术实验与课程设计》（第三版）机械工业出版社[3] 阎石《数字电子技术基础》（第五版）北京高等教育出版社g an employment tribunal claimEmployment tribunals sort out disagreements between employers and employees.You may need to make a claim to an employment tribunal if:you don't agree with the disciplinary action your employer has taken against youyour employer dismisses you and you think that you have been dismissed unfairly.For more information about dismissal and unfair dismissal, see Dismissal.You can make a claim to an employment tribunal, even if you haven't appealed against the disciplinary action your employer has taken against you. However, if you win your case, the tribunal may reduce any compensation awarded to you as a result of your failure to appeal.Remember that in most cases you must make an application to an employment tribunal within three months of the date when the event you are complaining about happened. If your application is received after this time limit, the tribunal will not usually accept it.If you are worried about how the time limits apply to you, take advice from one of the organisations listed under Further help.Employment tribunals are less formal than some other courts, but it is still a legal process and you will need to give evidence under an oath or affirmation.Most people find making a claim to an employment tribunal challenging. If you are thinking about making a claim to an employment tribunal, you should get help straight away from one of the organisations listed under Further help.If you are being represented by a solicitor at the tribunal, they may ask you to sign an agreement where you pay their fee out of your compensation if you win the case. This is known asa damages-based agreement. In England and Wales, your solicitor can't charge you more than 35% of your compensation if you win the case.If you are thinking about signing up for a damages-based agreement, you should make sure you're clear about the terms of the agreement. It might be best to get advice from an experienced adviser, for example, at a Citizens Advice Bureau. To find your nearest CAB, including those that give advice by e-mail, click on nearest CAB.For more information about making a claim to an employment tribunal, see Employment tribunals.The (lack of) air up thereWatch m Cayman Islands-based Webb, the headof Fifa's anti-racism taskforce, is in London forthe FootballAssociation's 150thanniversarycelebrations and willattend City's PremierLeague match atChelsea on Sunday."I am going to be at thematch tomorrow and I have asked to meet Yaya鼓。