基于nrf24l01的无线接收与发送系统翻译

1、苏州大学本科生毕业设计（论文）附件：外文文献资料与中文翻译稿外文文献资料收集：苏州大学 应用技术学院 10电子（学号1016405041） 林俊涵 the system design of wireless basketball timer based on mcu and nrf24l01 abstract: currently, basketball players must know the progress well in time in the game, the presence of electronic timer with led display influences the

2、 basketball games. the wired operation influences the control distance, control reliability, control efficiency and so on. so how to make it longer, anti-interference, easy operation and high efficiency is a difficult problem. a kind of wireless basketball timer is designed based on micro-computer u

3、nit (mcu) and wireless nrf24l01 module to compensate for the existing disadvantages, which has led digital tube of large size for the section number display and middle size for game display and 24s display.the user is easy to carry and control the timer wirelessly at any place in the basketball cour

4、t using the sending control device. the test results show that the system, easy to control and stable to operate, is reliable to transmit the wireless data. keywords: basketball timer, mcu , nrf24l01 , system design , wireless communication 1. introduction in the current basketball games, players ne

5、ed to know 24 sec and the remaining time of each period match in time; electronic timer with the advantages of its convenient operation, compact size and visualization has been widely used in basketball games. nba timing and score system was designed by a chip called 8031 of mcs-51.the system consis

6、ts of time counting, score counting, keyboards and display sub-systems (luo-sheng, 2004). a new timing and scoring equipment for basketball match was designed and made by chinese basketball association, used in 2004 cba league match and nba in beijing, which was helpful for the present timing and sc

7、oring equipment specialized in sport venues and has great room for development and application (zhang et al., 2006).the control system of basketball scoreboard with 16*16 matrix led was designed based on single-chip microcomputer, which could be off-line and continuous long-term operation and so on

8、(wei-yu et al., 2008).the design of hardware and software of timing-score system was achieved using 89c51, which had the functions of the total time and the total countdown, with its features of modular design, simple process structure, clear mandate and easy to prepare (han et al., 2009).the device

9、 was based on p89v51rb2 single-chip microcomputer, which can show the current section, the remaining time and the score, according to actual situations, the time and score can be amended (rong-jian et al., 2010).the countdown circuit was designed based on stc89c52 single-chip microcomputer, which ca

10、n countdown 999 days, accurate to seconds. the result of the experiment demonstrates the correctness and feasibility of the design (ze-shi, 2011).although these timer or score systems are convenient to use, there are some disadvantages during the use of them, some are inconvenient for both players a

11、s a result of small size and the position of use and some are inconvenient to install and repair and low efficiency and reliability and so on, because of the long cable connect of between sending device and receiving device.in the current chinese market, a electronic timer includes a sending device

12、which can be moved and a receiving device which is fixed on or over the basketball frame, can provide real-time information of time for players and audiences.still it is easy to cause bad connect because of the frequent connect of sending device and receiving device.in the basketball game, the baske

13、tball referee can need to move frequently, which is away from the sending device and cannot carry it due to the wire and must pass some information about the game to the live operator operating the sending device, which can lead to inaccurate and no timely information.according to the above reasons,

14、 a system based on mcu and wireless chip can be put forward which can send the information wirelessly and easy to carry, etc.2. basketball timer basketball timer is an indispensable instrument in basketball games, which used to show the information of time and quarter of the game.in addition, in ord

15、er to accelerate the game, players should shoot at the basket within 24 sec, otherwise it will break the rule. in common, basket timer is connected with receiver from transmitter by rs232 serial.however, the electric cables are fragile and difficult to operate.so, wireless data transmission is a bet

16、ter choice. some short distance wireless data communication such as bluetooth, zigbee, wi-fi that work on 2.4ghz, but these technologies are complicated and cost more, it is difficult to meet the rapid development and low cost requirement in general applications.nrf24l01 module is a new single chip

17、rf transceiver device launched by norway nordic semiconductor, built-in frequency synthesizer, a power amplifier, a crystal oscillator, a modulator module (zhang et al., 2004) and fused with enhanced shock burst technology, with advantages of high transmission rate, small volume and low power consum

18、ption.nrf24l01 chip with pcb antenna has 100 meters effective transmission distance, which will be satisfied with the design requirement. lq-nrf24l01 module of beijing long-qiu intelligent technology center is used in this system (xiu-mei and nai-an, 2004).in this system, the user (operator) can set

19、, modify and halt the match time by using its keyboard module.at the same time the match quarters changed, 24s ball-control time started and stopped. the system was easy to carry; anywhere within 100 meters from the timer display system it can be operated effectively. the overall system block diagra

20、m is shown in fig. 1.fig. 1: the system block diagram 3. hardware design of the system3.1. keyboard module: the keyboard module is mainly used to set and modify the section number, the game time and stop time of the section, 24 sec of the start and stop operation.considering the electronic basketbal

21、l timer required function and easy to extend, a 4*4 matrix keyboard is used.mcu scans the matrix keyboard and reads the key value through p0 port per 100 ms. the interface of the circuit is shown in fig. 2.fig. 2: keyboard and mcu interface circuit 3.2. sending and receiving (lq-nrf24l01) module: th

22、e system proposed a short distance of wireless data transmission design method based on the 2.4 ghz nrf24l01 chip, which has the advantages of low cost, low power consumption, fast development etc.nrf24l01 is a monolithic rf transceiver chip, with automatic response and re-transmitting function and

23、the data can be wrote through the spi bus.nrf24l01 chip has very low power consumption, for example, working current is only 9 ma and receiving current only for 12.3 ma while -6dbm power is transmitted.and with 125 channels available and a variety of low power modes so that the energy-saving design

24、more convenient, while the markets have many other modules based on nrf24l01 and easy to buy.lq-nrf24l01 module is used in the design. nrf24l01 has several working modes; sender-receiver model is only introduced, which has three modes such as enhanced shockburst tm, shockburst tm and direct mode.and

25、 that can be determined by configuration register.for the enhanced shockburst tm mode, inside fifo stack area is used and in order to minimize energy consumption the data are input with low speed, but are emitted with high speed (1 mbps). so enhanced shockburst tm technology can reduce average worki

26、ng current of the system.in the mode, nrf24l01 can process the prefix and crc check code automatically, which is completed by crc encoding and decoding circuit (hong-cai, 2008). during data transmission, the predix and crc check code are added automatically, meanwhile ce signal is set high for 10 us

27、 until the completion of the transmission.while receiving data, the prefix and crc check code will be deleted. interface circuit diagram is shown in fig. 3 between lq-nrf24l01 module and mcu, csn port of the module is a chip select with active low level, sck port for serial clock (spi clock).due to

28、no standard spi bus interface for atmel89c51 mcu, the function of spi bus is simulated by the software.miso is a host input / slave output port and mosi is a slave input/host output data port. irq port is the interrupt signal line, while data is sent successfully irq signal changed into low level.ce

29、 port is mode control of the chip, under the condition of low csn level, nrf24l01 status is decided by ce and nrf24l01 configration register.fig. 3: lq-nrf24l01module and mcu interface circuit 3.3. led display module:in order to improve the display effect and increased visibility, led digital displa

30、y device is used in the system. according to the display actual situation, led digital tubes of middle size are adopted to display the section number and the game time and led digital tubes of large size are adopted to display control time.because of these led digital tubes are drove by higher volt

31、which 51-mcu cannot afford, uln2803 driver chip with darlington tube of sufficient magnification is used (li et al., 2011) and the schematic diagram is shown in fig. 4. in order to reduce the complexity of the system, the dynamic scan mode is used to control the led display here. the valid bit displ

32、ay method can improve the mcu efficiency, where once the bit is a valid value it could be displayed. fig. 4: led digital tube and mcu interface circuit 4. software design of the system c or asm language can be used to design the mcu program with 51 kernels. and c language with the characteristic of

33、simple and easy to understand, so it could accelerate the developed program speed,at the same time convenient transplantation between different mcus.asm language is relatively difficult to read and graft and the rate of development is slower, but it has the highest executable program efficiency (hon

34、g-cai, 2008; yun-xin et al., 2009).c language is chosen in the system because of the current c language in the powerful compiler can already has the similar efficiency compared with assembler language. wireless basketball timer software design mainly includes the transmitting and receiving parts.4.1

35、. transmitting program design: main functions of the transmitting part are as follows: at first,the initialization of mcu and nrf24l01 module and nrf24l01 is set transmitting mode, then the keyboard is scanned at fixed time and the key value is got and that is transmitted wirelessly which is encoded

36、 by the nrf24l01 module. transmitting mode configuration of nrf24l01 module is as follows (zhu and zhang, 2011): （1）set csn high,ce low and configuring mode （2）delay above 130 us （3）configuration data is written to the lq-nrf24l01module by i/o port of mcu （4）set csn low, completing configuration （5）

37、set the ce high, nrf24l01 for tx mode （6）delay above 130 us （7）data to be transmitted is written to the lq-nrf24l01 fifo buffer by i/o port of mcu （8）set ce is low, transmitting through shockburst tx mode （9）clear fifo buffer after completing transmission （10）the program diagram is shown in fig. 5.f

38、ig. 5: transmitting program diagram 4.2. receiving program design:main functions of the receiving part are as follows: while a valid packet could not be received, the data of different display buffers are read and displayed on the corresponding led digital tube. and while a valid packet could be rec

39、eived, the receiving control system is interrupted and the received data in the nrf24l01 module are read and stored to the corresponding display buffers. program flow diagram is shown in fig. 6.fig. 6: receiving program diagram, (a) main program diagram of the control system, (b) interrupt service r

40、outine diagram receiving mode configuration of nrf24l01 module is as follows (zhu and zhang, 2011):（1）set ce high, nrf24l01 for receiving mode（2）while rx_dr bit of the status register becomes to high level, that confirms the fifo buffer of nrf24l01 has received the data and mcu reads these data by t

41、he interrupt mode（3）clear fifo buffer after completing to read data5. conclusionthe study introduced a kind of wireless basketball timer based on the mcu and nrf24l01 module, the current some problem can be solved such as wiring inconvenient an so on.the system has the advantages of simple structure

42、, convenient installation and repair, convenient operation, low cost and flexible layout, so it has great value in practical generalization and application.第 17 页中文翻译稿翻译：苏州大学 应用技术学院 10电子（学号1016405041） 林俊涵基于单片机和nrf24l01的无线篮球定时器的系统设计摘要：目前，篮球运动员必须及时地很好的知道比赛的进展情况，带有led显示屏的电子定时器的存在对篮球比赛产生了很多影响。有限操作影响控制的距

43、离，控制的可靠性和控制的有效性等等。因此如何使它更长距离控制，有更高的抗干扰性，有更简便的操作和高度的有效性是一个困难的问题。一种基于单片机（mcu）和无线芯片nrf24l01设计模块的无线篮球计时器可以用来补偿以上的缺点，它有大尺寸led数码管用来段数显示和中型的尺寸作为比赛和24秒的显示。裁判可以在篮球场上任何地方使用发送装置对定时器进行控制，并且它很容易携带。试验结果表明，该系统稳定，易于控制和操作，使无线传输数据具有可靠性。关键词：篮球计时器，单片机，nrf24l01，系统设计，无线通信第1章 引言在目前的篮球比赛中，运动员需要知道24秒，以及比赛期间每个时间段剩余时间;电子计时器以其

44、简便的操作，体积小和易于观看的优势，已被广泛应用于篮球比赛。nba使用由8031mcs-51构建的计时和评分系统。该系统由计时，计分，键盘和显示子系统构成。 一个由中国篮球协会设计和制造的新的篮球比赛计时计分设备，用于2004年北京cba和nba联赛。这有助于在体育场馆的目前用于计时计分的专用设备的发展和应用，同业具有巨大的发展空间（张等人.2006）。16*16矩阵led篮球计分牌控制系统是基于单片机设计的，并且可以长期连续地离线运作等。计时评分系统的硬件和软件的设计是采用89c51单片机实现的，具有总时间计算和倒计时功能，其设计模块化，程序结构简单，指令清晰并且容易配备。该设备是基于p89

45、v51rb2单片机，它可以显示当前部分，剩余时间和得分，根据实际情况，时间和分数可以修改。倒计时电路是基于stc89c52单片机设计的，它可以倒计时999天，精确到秒。实验结果证明了设计的正确性和可行性。虽然这些定时器和评分系统方便使用，但他们在实际使用中仍然存在一些弊端，由于小尺寸和摆放位置导致了双方球员的不便，还有难以安装和修理的不便，这些都是发送装置和接收装置之间的长电缆导致的。在目前的中国市场，一个由可以移动的发送装置和一个固定在篮球框的接收装置制成的电子计时器，便可以为运动员和观众提供时间的实时信息。还是很容易造成因为频繁地连接发送和接收设备而造成的接触不良。在篮球比赛中，篮球裁判可

46、能需要经常移动，发送设备因为电线的缘故不能随身携带，但必须传递关于比赛的资料，这就要远离发送设备。只能由操作人员操作发送设备，这可能会导致信息的不准确和不具有实时性。基于以上原因，基于单片机和无线芯片可以做出具有无线传输和方便携带等功能的系统。第2章 篮球计时器篮球计时器在篮球运动中是不可缺少的工具，用于显示时间和比赛阶段信息。此外，为了加快比赛节奏，选手必须在24秒内投篮，否则将算作犯规。一般而言，篮球定时器通过连接rs232串口进行信号收发。然后电缆是脆弱并且难以操控的。因此无线数据传输是更好的选择。一些短距离无线数据通信技术，如蓝牙，wifi等工作在2.4ghz，但是这些技术复杂，成本高

47、，难以满足快速发展的一般应用的低成本要求。nrf24l01模块是一个由挪威北欧半导体推出新的单片射频收发装置，内置频率合成器，功率放大器，晶体振荡器，调制器模块并融合增强的冲击地压技术，具有传输速率高，体积小，功耗低的优点。基于nrf24l01芯片的pcb天线有100米的有效传输距离，这满足设计要求。北京长秋智能技术中心的lq-nrf24l01应用于本系统。在这个系统中，用户（操作员）可以通过使用键盘模块建立，修改和停止比赛的时间。包括比赛段的改变，24秒的开始和停止。该系统便于携带，在计时器显示系统100米范围内的任何地方都可以有效地操作。该系统总体框架如图1所示。图1 系统模块框图第3章

48、该系统的硬件第3.1.节 键盘模块键盘模块主要用于设置和修改比赛的阶段，比赛开始时间和终止时间，24秒的启动和停止。考虑到电子篮球定时器所需要的功能和已与扩展的特性而使用了4*4的矩阵键盘。单片机扫描矩阵键盘通过p0口每100毫秒读取一次键值。该电路的接口，如图2所示。图2 键盘和单片机的接口电路第3.2.节 发送和接收（lq-nrf24l01）模块该系统提出了一种基于nrf24l01芯片工作频率为2.4 ghz的短距离无线数据传输的设计方案，具有成本低，功耗低，快速发展等特点。nrf24l01是单片射频收发芯片，具有自动应答、转发功能，可以通过spi总线写入数据。nrf24l01具有非常低的功耗，例如当发送频率为-6dbm时工作电流只有9ma，接收时电流为12.3ma。有125个频道和多种低功耗模式，使节能设计更方便，而市场上也有许多其他基于nrf24l01的模块，并且很容易购买到。本设计中应用lq-nrf24l01模块。nrf24l01具有多种工作模式，本课题只介绍信号收发模式，它还具有三种模式如增强型，节能型和直接模式。这可以通过配置寄存器确定。在增强模式下，在先进先出的堆栈区使用，以减少能量消耗，但是以高速发射的(速度高达1mbps)。因此，增强型单片机 tm技术可以降低系统的平均工作电流。在该模式下，nrf24l01的可自动加工前缀和crc