外文文献及翻译基于STC89C52单片机的多路抢答器设计.docx

1、外文文献及翻译基于STC89C52单片机的多路抢答器设计2010 International Conference on Intelligent Computation Technology and AutomationDesign and Implement of Responder Based on Freescale HCS12 Single Chip MicrocomputerCheng Qiming, Cheng Yinman, Wang Mingmei, Chang LinCollege of Electric Power and Automation Shanghai Unive

2、rsity of Electric PowerChangyang 2588 road, Yandpu district, Shanghai 200090, China E-mail :*AbstractAn 8-channel responder based on Freescale HCS12 single chip microcomputer is designed. The responder can display the number of the first player correctly. It also can count the scores and show the pl

3、ayer with the highest score. The system includes four modules: CPU12, the SCI serial communication, digital display tube and timer. When competition signal input, it is been caught and then cause interruption, the timer is used to time accurately, the serial port is used to send and receive the star

4、t answer signal, judgment signal and other signals, the digital display tube is used to show the scores of the current player . LCD display tube shows subjects and answers. So the basic functions of the responder are achieved.Keywords-responder; single chip microcomputer; timer; input capture; inter

5、ruptionI.INTRODUCTIONResponder is also known as the first signal discriminator, which is widely used in various competitions. It can judge the number of the first player accurately, fairly and intuitively. Currently, a variety of quiz responder has emerged on the market, in which a small responder i

6、s commonly designed with small-scale digital integrated circuit. Although the technology has been quite mature, but it is simple function, low intelligence, high fault, simple display, less flexibility, not convenience for upgrade, it has been unable to meet all kinds of requirements for intellectua

7、l competitions and variety shows. Therefore, it is necessary to develop some kinds of responder which are more suitable for applications.In recent years, with the rapid development of science and technology, the applications of single-chip microcomputer are becoming widely, which promotes the develo

8、pment of traditional measurement and control technology. In this paper, Freescale HCS12 1-3 is designed as a core component to achieve an intelligent digital responder with 8-channel 4-8, it has some breakthroughs on technology, function and other aspects, comparing with the past responder. It is ch

9、aracterized by simple structure, powerful, good reliability, practicability, so that the competition can really carried out on just, fair and open rules.II.FUNCTION OF RESPONDERThe basic functions of responder designed in this paper are:(1)The system can limit the competition time and answer time of

10、 the alarm;1 This work is supported by Leading Academic Discipline Project of Shanghai Municipal Education Commission (Project Number: J510301， J510303)978-0-7695-4077-1/10 $26.00 2010 IEEE DOI 10.1109/ICICTA.2010.1281127(2)The system can identify the answer signal and identify the players number;(3

11、)The system can calculate score for each player and display the scores.Responder can accommodate 8 players numbered 1 to 8. In addition, LED digital tubes are designed to display the latched data. After race host clears the system, if participants press switch, and after answer is certificated wheth

12、er it is correct or not, the number of first player to answer in action is immediately shown by digital tubes. Responder should have a strong ability to distinguish players to answer in the action, its resolution reaches at least a few ms.III.IDEAS OF RESPONDER DESIGNAfter the requirements and funct

13、ions of responder are analyzed, the following circuits are required in general:AResponder circuitThe circuit has two functions: one is to identify the number of the player who press button, and to save the number; the other is to prohibit the other players from buttoning or to make other buttons not

14、 available.BTiming circuitsHost can set competition time and answer time by the time pre-set-circuit. If nobody can answer question within the set time, all players will not get score, then the host will announce the answer. Besides, if someone gets the chance to answer the question, but does not gi

15、ve the right result before the allowable time, he or she wont get the score, the overtime signal will be also send, the host will declare the right answer. Freescale HCS12 contains timer module, the timer module can be directly used.COvertime circuitHCS12 will send overtime signal when time goes bey

16、ond the set time, this signal will be transferred to the PC computer by the serial port. The next question will be proceeded to answer.DScores count and display circuit.When host presses the answer key, it is time to start to answer, if one player presses the answer key, his or her number will be re

17、corded, his or her score will be counted and displayed on the LED digital tubes.Bedside the circuits designed above, some necessary logic designs are also necessary. The logic designs are as following:First, the host will read the question which will show in the LCD; next, the PC computer will send

18、letter “k”, which means that play is beginning to competition. At the same time, timing circuit starts to work, if nobody gets the chance to answer the question within permitted time, microcontroller will send the word “chao shi” to PC computer; If someone presses the competition key within the spec

19、ified time, microcontroller will send his or her number. If the time goes beyond the permitted time, PC computer will send “next” which means turning to the next question, the next question will be automatically showed to answer. If some player gets the chance to answer the question, his or her numb

20、er and scores will decrease 1 automatically and show in the digital tubes, then microcontroller sends “next” to go on the next question. If the score is few than 0 after decreasing, player is eliminated. The right answer will show on the LCD. Finally, if all the questions are done, microcontroller w

21、ill send “e” to end the game, then the scores of all players will be computed, the highest one will be shown on the digital tubes.IV.DESIGN OF RESPONDER HARDWAREResponder hardware is firstly designed; Responder hardware is taken directly from the hardware resources of Freescale HCS12 development boa

22、rd developed by Suzhou University. The development board takes MC9S12DG128 as the core, using modular design approach, it extracts part of I/O resources, and it also provides each module with a corresponding interface circuit. It also provides A/D input channels, PWM low-pass filter circuits, 16-key

23、 keyboard input channels, 8-bit digital I/O circuits, SPI I/O circuits, SCIcommunication circuits, I2C bus I/O expansion circuits and so on.In this paper, the hardware modules, the pin connections and the corresponding interfaces of the development board are listed and unified to redesign by actual

24、needs of the system. Figure 1 shows the hardware structure diagram of the selected part of development board.Figure 1. Diagram of hardware structureASelection of hardware modulesThe responder designed in this paper is relatively simple, the I/O ports and the modules involved are not many.(1)The syst

25、em uses push-button switch as the competition key, which is generally used as a switch input, there are 0 and1. Here, the system need know whether the button is switched by somebody, the system need not care about the switch on or off.(2)Timer module is indispensable in timing circuit. Here, the tim

26、er modules functions are to limit time, and to captureinput signals. This will be followed some of the circuit design described in detail.(3)LED digital tubes are used to show the participants number and scores in the display circuit. The system records the players number and the corresponding score

27、, and then transmits to the LED digital tubes through I/O ports. LCD is achieved by external connection module; it is used to display questions and answers.(4)LED small light is used to show whether somebody presses the competition button. If player answer, the small light will be bright, otherwise,

28、 it will not light.(5)SCI module is necessary in serial communication port. Since the signal that starts to answer needs to be send by PC computer, if there is no serial communication port, the whole system will be paralyzed. The function of SCI module is thatreceives the signal to HCS12, and then s

29、ends the players number to PC.BDesign of hardware circuits1) Competition circuit designCompetition circuit captures competition signals by means of input capturing; there will be a interruption once the push- button switch jumps. 8 push-button switches are connected with 8 channels, so the system ca

30、n know which player competes to answer the question by reading corresponding channel. In this paper, the 8 channels connect with input capture channels PT0 PT7 of HCS12.2)Timing circuitAs the HCS12 has its own timing module, timing circuit dont need to be designed, and internal timing module of HCS1

31、2 can be directly used.3)Overtime reminding circuitSmall light or buzzer could connect with any I/O port, but the system should ensure the selected I/O ports have not conflict with the I/O ports occupied by the module. Once the specified time is over, I / O port send a high level, and the LED small

32、light is on. In this paper, the first pin of PA port is chosen as the alarm signal port; this pin is connected to the testing of small light.4)Electronic counter and display circuitThe scoring scores can be resolved by programming, but the displaying scores needs hardware connection, LED digital tubes and LCD are connected with corresponding I/O ports of HCS12, external LCD module should have the function of displaying Chinese characters.5)Communication connectThe development board has a 9-pin cable of RS