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1、重庆理工 大学文献翻译二级学院计算机科学与工程学院班 级 112030701学生姓名李洋学 号译文要求1、译文内容必须与课题(或专业)内容相关,并需注明详细出处。2、外文翻译译文不少于2000字;外文参考资料阅读量至少3篇(相当于10万外文字符以上)。3、译文原文(或复印件)应附在译文后备查。译文评阅导师评语(应根据学校“译文要求”,对学生外文翻译的准确性、翻译数量以及译文的文字表述情况等作具体的评价)指导教师:基于控制蓝牙数据传输系统摘要:蓝牙协议,是一种基于蓝牙数据传输系统的研发MCU控制协议已经被提出。在 系统中,其中,所述蓝牙HCI协议已经被嵌入MCU处于用于控制UART蓝牙模块, 使
2、蓝牙设备的蓝牙网络中建立连接,并自动传输数据。在硬件设计中,芯片C8051F020 被选择作为主机控制器。由于芯片C8051F020有两个UART串行接口,可满足设计 要求,简化电路和增强系统的抗干扰能力。在系统中使用的蓝牙模块是CSR蓝牙芯 4与蓝牙标准2.01类具有高的信号灵敏度的优点,长距离连接和易于使用。关键词:蓝牙;数据通信;MCU; HCI; UART1荷介蓝牙是一种无线电技术,支持在短距离设备的通信,以及制备可能众多设备之间 进行无线信息传输。蓝牙在一系列被使用技术,方法和理论对硬件和软件的设计。例 如,无线通信和网络技术,工程和软件可靠性理论,协议测试技术,标准的描述语言, 内
3、置RTOS,跨平台开发和图形用户接口技术,接口技术的软件和硬件,和CMOS 芯片集成技术等1。由于小尺寸和低功耗,蓝牙应用的技术比一台计算机的外围设 备等等。它可以在任何数字设备的内部被集成,特别是对于微器件和便携式设备,其 不要求在传输速度高品质。在现代生活中,随着数字技术的快速发展,无线信息传输各种数码设备和计算机 之间经常需要。尤其是在工业控制和数据采集器,连接电脑和MCU之间的安全无线 的方式和交换信息是特别重要的。基于这个问题,基于单片机蓝牙通信系统中控制在 本文提出。该系统是由微控制控制,并且可以与任何通信其他蓝牙设备中的蓝牙网络 的范围内,如地窖电话,PDA等。蓝牙协议栈的概述2
4、.1协议标准和蓝牙规范蓝牙采用多种协议。核心协议由行业组织蓝牙定义SIG(特别兴趣小组)。附加议 定书已经从其他标准组织采纳。在这部,核心协议和那些通过协议被广泛采用将全面 的概述讨论。核心协议提供了蓝牙产品的标准和资格。目前,蓝牙规范有几个版本 1.0,1.1,2.0,2.1,3.0,4.0 2。4月21日,2010年,蓝牙技术联盟完成了蓝牙核 心规范4.0版,其中包括经典支持蓝牙,蓝牙高速,低功耗蓝牙协议。高速蓝牙是基 于无线网络连接,和传统蓝牙由传统的蓝牙协议3。蓝牙是一个标准线更换通信协 议主要用于低功耗消费,具有短的范围(功率级依赖性:100米,10米和1m,但范 围内变化在实践;见
5、下表)根据每个设备低成本的收发器芯片。因为这些设备使用的 无线电(广播)的通信系统,它们不必在视线彼此的线。表中每个类的参数CL15SMaxiilium Permitted PowerR戢mWdBmClass 110020100 metersClass 22.5410 metersClass 3101 meter在大多数情况下,2级的设备的有效范围,如果他们连接到一个1级收发器延伸 时,相比纯粹的2级网络。这是由更高的灵敏度和传输完成1类设备的电源。而蓝牙 核心规范并授权为最低范围内,该技术的范围是应用特定并且是没有限制的。制造商 可以调整他们的实现的范围需要支持个别用例。蓝牙规范包括两部分:
6、协议规范和应 用程序框架。协议规范定义了每个层和应用程序框架蓝牙协议指示如何使用这些协议 来制造的应用程序。该协议栈可分为三个部分从上到下:传输协议,中介协议和应用 协议。该传输协议,包括LMP,L2CAP,HCI,在负责确认蓝牙设备的相互位置,建 立物理链路和逻辑链路的和管理它们。对高层次应用协议或调解协议提供支持其中蓝 牙逻辑链路上工作,并提供应用层的各种方案接口(如RFCOMM,SDP,红外,PPP, UDP,TSC和AT指令集等)。2.2蓝牙核心协议蓝牙核心协议被分成四部分:1)基带协议(BP)基带层,也被称为基带包,在蓝牙协议中的物理层协议堆叠。在蓝牙基带从像其 他服务管理物理信道和
7、链路分开纠错,数据美白,跳选择和蓝牙安全。基带层位于顶 在蓝牙堆栈的蓝牙无线电层。基带协议是作为一个链接控制器,其与链路管理器适用 于进行像链路连接的链路级例程和功率控制。基带还管理异步和同步链路,处理数据 包和没有寻呼,查询到该地区的访问和查询蓝牙设备。2)链路管理协议(LMP)它用于建立蓝牙设备之间的链路,以及用于无线电链路的该控制。它是主机控 制器上实现。3)逻辑链路控制和适配协议(L2CAP)它是适配协议,它为高级别转移层协议屏蔽基带协议和应用层协议。它提供了高 级别应用层和传输层,用更有效的数据包格式。它被用于使用复用的两个设备之间的 多个逻辑连接不同更高级别的协议。它提供了分段和在
8、空气包的重新组装。在基本模 式,L2CAP提供数据包具有可配置高达64KB的有效载荷,有672字节默认的MTU 和48字节的最低强制支持MTU。在重传与流动控制模式,L2CAP可配置为可靠或 同步数据每通过执行重传和CRC校验通道。蓝牙核心规格附录1增加了两个额外的 L2CAP模式的核心规范:增强重传模式(ERTM)4和流模式(SM)的5。这些模 式有效地弃用原来的重传和流控制模式。在任何这些模式的可靠性是由下层任选和/ 或附加地保证通过配置重传和冲洗超时数蓝牙BDR / EDR空中接口(时间在此之后, 无线电将刷新包)。顺序排序由下层保证。4)服务发现协议(SDP)SDP起到蓝牙框架非常重要
9、的作用,它是所有的用户模式的基础。它许一个设备 发现其他设备,以及它们的相关联的参数的支持服务。例如,移动电话连接到蓝牙 耳机时,SDP将被用于确定哪些蓝牙配置文件是由耳机(耳机模式,免提模式,高级 音频支持传输模式(A2DP)等),并连接到他们每个人所需要的协议多路复用设置。 每个服务都由一个全局唯一标识符(UUID),官方服务(蓝牙标识配置文件)分配一 个短表UUID(16位,而不是完整的128)。在蓝牙系统,只能通过SDP,客户可以 获取设备的信息,服务和服务功能的信息来建立不同SDP层链路。2.3。HCI 协议HCl (主机控制器接口)的主机栈之间的标准化的通信(例如,个人电脑或手机
10、OS)和所述控制器(蓝牙IC)。该标准允许的主机栈或控制器集成电路以最小适应交 换。盐酸属于蓝牙协议栈,这是一个标准接口,蓝牙定义规范。它适合用于蓝牙通信 模块的硬件。该定义描述了 HCI驱动器和主机控制器固件之间的接口。HCI传输层 是蓝牙主机与蓝牙主机控制器之间的物理接口。目前,HCI传输层的物理接口是由通 用串行总线(USB)构成的,串行端口(RS232),通用异步收发器(UART)和个人 电脑存储卡7。最常用的是USB (个人电脑)和UART(在移动电话和PDA)。上的 UART传输层,所述蓝牙HCI Protocol可以两种UART串行端口间使用它们是在相同 的PCB板。串行和并行形
11、式之间的转换的基本方法。数字串行传输通过一个单一的金属丝或其他媒体信息(位)比平行更具成本效益 通过多线传输。通常,在UART不产生或接收的不同项之间所使用的外部信号直接装备。单独的 接口设备用于UART的逻辑电平信号转换为并从外部信令水平。外部信号可以是许 多不同的形式。示例电压信号标准RS-232, RS-422和RS-485从环评。历史上,存 在或无电流(电流环路)的在电报电路中使用。一些信令方案不使用电线。这样的例 子有光纤,红外和蓝牙在其串行端口配置文件(SPP)。一些信令方案使用的载波信 号的调制(带或不带线)。例子音频信号的调制与电话线调制解调器,具有数据无线 电RF调制,DC-
12、LIN用于电力线通信。通信可能是“全双工”或“半双工”。在系统中,UART使用RS232接口参数配置,如表II表II。RS232接口参数配置Baud rateSpecific mfonnationData bits8Parityivo neStop bit1Flow controlRTS/CTSFlow time3ni5使用RTS / CTS是避免UART缓冲区溢出。它允许主机控制器或蓝牙主机传送数 据时的CTS的值是1,并且不当值为0完全流动时间是最大从RTS的值设置为0到 流传输完成时间。UART信号线设置调制解调器模式为null,RS232的连接状态。要 RS232,当地TXD与RXD遥
13、控器,反之亦然联系。的UART具有校正的功能。当蓝 牙主机失去了与连接它必须复位主机控制器。出RS232的同步意味着HCI分组指示 器或者HCI分组长度超出的范围。主机控制器将硬件宕机的信息发送到蓝牙主机, 通知错误消息的蓝牙主机中,如果它是从主控制器和蓝牙之间的同步。对于重新同步, 主机控制器需要接受来自蓝牙主机的命令复位。系统设计图1.系统硬件设计研究蓝牙协议之后,我们通过使用模式取系统的设计,该蓝牙模块(蓝牙)与主 机控制器(MCU)连接。在系统中,MCU将接受AT命令来控制UART蓝牙模块。 该系统设计有几个技术指标,如下,1)自动连接模式这种连接方式,我们应该一对具有相同的硬件两个蓝
14、牙,MCU器件结构,但事 先不同的物理地址。这两个设备会,如果他们自动连接到达连接距离。2)FLASH 存储A级FLASH芯片MCU上进行。这是要被发送可以被存储在FLASH和它的数据 当它建立了两个设备之间的链接将被自动发送。该数据将不被发送不止一次。3)搜索和选择功能主设备可以搜索所有装置与它相同的模型,并与其他装置网络中的蓝牙功能。搜 索结果的格式为“设备地址+设备类型+信号强度“,而主设备将决定哪些设备搜寻 后链接。4)接收模式该系统两个接收模式:一种是,蓝牙MCU器件与其他连接像PC和智能终端智 能终端是负责数据传输的。另一种是不存在终端与蓝牙-MCU设备连接和该数据将是 发送到FL
15、ASH直接。该模式消除终端环节,使设备更便携,而且设备可以随时与他 人建立和传输数据自动链接没有通知任何他人或触发任意键。该系统被分成两个部 分,一个是蓝牙模块与蓝牙HCI协议,并另一种是MCU从而起到主机控制器的作用, 进行它的闪存芯片。系统硬件结构系统由微控制器串行端口上的控制,可以配置蓝牙模块的参数和自动传输数据。图2.蓝牙MCU系统的硬件结构4.1。芯片选择MCU该系统主控制器C8051F020选择的芯片。C8051F020的是混合信号系统MCU。 它是用CIP-51核兼容并且它也具有SPI接口和两个UART串行接口,可满足设计的 要求,简化了电路,提高系统的抗干扰能力C8051F02
16、0拥有更少的扩展芯片,结构 简单,更多的资源优势,更高运算速度快,编程简单,易升级,与普通MCU相比。 有可能保证了可靠性和稳定性。蓝牙模块蓝牙模块采用CSR蓝牙Core4与蓝牙2.0标准的蓝牙芯片类1.蓝牙Core4具有高 的信号灵敏度的优点,长距离连接的和易于使用。它可以与AT命令查看和配置参数, 满足要求数据传输的无线串口上。蓝牙模块支持所有蓝牙协议。它采用串行通信方式 和可以通用串行接口和蓝牙数据传输之间进行转换。与模块多从的结构可与具有最多 7个远程蓝牙主设备进行通信SPP在它在同一时间。它使用AT命令来设置控制参数 或发出控制命令和支持多种波特率。硬件流控制,还支持和最大波特率连接
17、 1382400bps。模块的通信频带是蓝牙标准的2.4GHz。该蓝牙模块包括三个部分:基 带控制器,蓝牙适配器和2.4GHz的RF模块。蓝牙适配器,增加额外的功率放大器 和外置天线,扩展了蓝牙通信范围使得最大连接距离可以在理想的环境中达到 1800M。FLASH 芯片FLASH芯片采用Atmel公司生产的AT45DB161D-SU。其存储容量为16M,和供 给电压范围为2.7V-3.6V,最大工作电流为15mA4.2。主控制器和蓝牙模块连接MCU使用与22.1184MHz频率的晶体,和连接波特率蓝牙模块和MCU是38400个基 点。单片机系统及其发挥主控制器的作用带有蓝牙模块的连接应该是人机
18、交互。HCI 包括两部分,一个是主控制器其与蓝牙模块连接,而另一个是命令接口的软件。 五,结论基于蓝牙协议,尤其是蓝牙核心协议和蓝牙HCI的研究协议,一种蓝牙数据传输 基于MCU的控制系统在文中提出,提供产品开发低成本和便携式蓝牙设备的解决方 案。通过使用该系统,连接可以自动两个蓝牙设备之间建立具有相同的模式,但不同 的物理地址,其被预先配对。该系统具有制定了关于终端的对等层的文件传输协议, 使得文件可传送自动。在此基础上,该系统可扩展到点的模式,以多点或特设网络。原文:MCU-Controlling Based Bluetooth Data TransferringJia LIU,Guang
19、min SUN*, Dequn ZHAO, Xu YAO, Yihang ZHANG AbstractBased on researching of Bluetooth Protocol, a kind of Bluetooth data transferring system based on MCU-controlling has been proposed in the paper. In the system, the MCU in which the Bluetooth HCI protocol has been embedded is used to control the Blu
20、etooth module on UART and make the Bluetooth devices in the Bluetooth network establish connection and transfer data automatically. In the hardware design, the chip C8051F020 is selected as the host controller. Because chip C8051F020 has two UART serial interfaces, it can meet the requirement of des
21、ign, simplify the circuit and enhance system anti-jamming capability. The Bluetooth module used in the system is CSR Bluetooth Core 4 with Bluetooth Standard 2.0 class 1 which has the advantages of high signal sensitivity, long distance of connection and easy to use.Keywords: Bluetooth; Data Communi
22、cation; MCU; HCI; UARTIntroductionBluetooth is a radio technology, supporting communication of device in short distance, and making wireless information transfer between numerous devices possible. The Bluetooth has been used in a series of technologies, methods and theories for hardware and software
23、 designs. For example, wireless communication and technologies in network, engineering and software dependability theory, protocol testing technology, standard describing language, built-in RTOS, cross-platform development and graphical user interfaces technology, interface technology for software a
24、nd hardware, and CMOS chips integration technology etc.1. Because of the small size and the low power, the application of Bluetooth technology is more than a compuperipheral device. It can be integrated inside of any digital device, especially for micro devices and portable devices, which do not req
25、uire high quality on transfer speed. In modern life, with fast development of digital technology, the wireless information transfer is needed frequently between all kinds of digital devices and computers. Especially in industrial control and data collection, a secure wireless way to connect and exch
26、ange information between computer and MCU is particularly important. Based on the problem, a Bluetooth communication system based on MCUcontrollingis proposed in the paper. The system is controlled by MCU and can communicate with any other Bluetooth device in the range of Bluetooth network, such as
27、cellar phone, PDA etc.Overview of Bluetooth Protocol Stack2.1. Protocol Standards and Specification of BluetoothBluetooth uses a variety of protocols. Core protocols are defined by the trade organization Bluetooth SIG (Special Interest Group). Additional protocols have been adopted from other standa
28、rds bodies. In this section, an overview of the core protocols and those adopted protocols that are widely used will be fully discussed. Core protocols provide the standards and qualification for Bluetooth products.Currently, the Bluetooth specification has several versions 1.0, 1.1, 2.0, 2.1, 3.0,
29、4.0 2 On April 21, 2010, the Bluetooth SIG completed the Bluetooth Core Specification version 4.0, which includes ClassicBluetooth, Bluetooth high speed and Bluetooth low energy protocols. Bluetooth high speed is based on Wi-Fi, and Classic Bluetooth consists of legacy Bluetooth protocols 3Bluetooth
30、 is a standard wire-replacement communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 100 m, 10 m and 1 m, but ranges vary in practice; see table below) based on low-cost transceiver microchips in each device. Because the devices use a radio
31、 (broadcast) communications system, they do not have to be in line of sight of each other. TABLE I. PARAMETERS OF EACH CLASSMaximum Permitted Pon ertiipproxiniste)mWdBmClass. 110020100 inet-ersClass 22.5410 metersClass 3101 meterIn most cases the effective range of class 2 devices is extended if the
32、y connect to a class 1 transceiver, compared to a pure class 2 network. This is accomplished by the higher sensitivity and transmission power of Class 1 devices. While the Bluetooth Core Specification does mandate minimums for range, the range of the technology is application specific and is not lim
33、ited. Manufacturers may tune their implementations to the range needed to support individual use cases.The Bluetooth Specification includes two parts: Protocol Specification and Application Framework. The Protocol Specification defines Bluetooth protocols on each layer and the Application Framework
34、indicates that how to use those protocols to manufacture applications.The Protocol Stack can be divided into three parts from top to bottom: Transfer Protocol, Mediation Agreement and Application Protocol. The Transfer Protocol, including LMP, L2CAP, HCI, are in charge of confirming the mutual posit
35、ion of Bluetooth devices, establishing the physical link and logical link and managing them. The Mediation Agreement provide support for high-level application protocol or programs which work on the Bluetooth logical link, and provide application layer with all kinds of interfaces (such as RFCOMM, S
36、DP, IrDA, PPP, UDP, TSC and AT instruction set etc.).Bluetooth Core ProtocolBluetooth Core Protocol is divided into four parts as:Baseband Protocol (BP)Baseband layer, also known as baseband packet, is a physical layer protocol in the Bluetooth protocol stack. The Baseband in the Bluetooth manages p
37、hysical channels and links apart from other services like error correction, data whitening, hop selection and Bluetooth security. The Baseband layer lies on top of the Bluetooth radio layer in the Bluetooth stack. The baseband protocol is implemented as a Link Controller, which works with the link m
38、anager for carrying out link level routines like link connection and power control. The baseband also manages asynchronous and synchronous links, handles packets and does paging and inquiry to access and inquire Bluetooth devices in the area.Link Management Protocol (LMP)It is used to establish the
39、link between Bluetooth devices, and for the control of the radio link. It is implemented on the host controller.Logical Link Control and Adaptation Protocol (L2CAP)It is an adaptation protocol which shield baseband protocol for high-level transfer layer protocol and application layer protocol. It pr
40、ovides high-level application layer and transfer layer with more effective data packet format. It is used to multiplex multiple logical connections between two devices using different higher level protocols. It provides segmentation and reassembly of on-air packets.In Basic mode, L2CAP provides pack
41、ets with a payload configurable up to 64kB, with 672 bytes as the default MTU, and 48 bytes as the minimum mandatory supported MTU.In Retransmission & Flow Control modes, L2CAP can be configured for reliable or isochronous data per channel by performing retransmissions and CRC checks.Bluetooth Core
42、Specification Addendum 1 adds two additional L2CAP modes to the core specification: Enhanced Retransmission Mode (ERTM) 4 and Streaming Mode (SM).These modes effectively deprecate original Retransmission and Flow Control modes.Reliability in any of these modes is optionally and/or additionally guara
43、nteed by the lower layer Bluetooth BDR/EDR air interface by configuring the number of retransmissions and flush timeout (time after which the radio will flush packets). In-order sequencing is guaranteed by the lower layer.Service Discovery Protocol (SDP)SDP play a very important role in Bluetooth fr
44、amework and it is the base of all of user mode. It allows a device to discover services supported by other devices, and their associated parameters. For example, when connecting a mobile phone to a Bluetooth headset, SDP will be used for determining which Bluetooth profiles are supported by the head
45、set (Headset Profile, Hands Free Profile, Advanced Audio Distribution Profile (A2DP) etc.) and the protocol multiplexer settings needed to connect to each of them. Each service is identified by a Universally Unique Identifier (UUID), with official services (Bluetooth profiles) assigned a short form
46、UUID (16 bits rather than the full 128). In Bluetooth system, only by SDP, can clients get information of devices, information of service and service features to establish different SDP layer link”.HCI ProtocolHCI (Host Controller Interface) standardizes communication between the host stack (e.g., a
47、 PC or mobile phone OS) and the controller (the Bluetooth IC). This standard allows the host stack or controller IC to be swapped with minimal adaptation.HCI belongs to Bluetooth Protocol Stack, which is a standard interface, defined by Bluetooth Specification. It fits for the hardware of Bluetooth
48、communication module. The definition describes the interface between HCI driver and host controller firmware.HCI transport layer is the physical interface between Bluetooth host and Bluetooth host controller. Presently, the physical interface of HCI transport layer was constituted by Universal Seria
49、l Bus (USB), Serial Port (RS232), Universal Asynchronous Receiver Transmitter (UART) and personal computer memory card7The most commonly used are USB (in PCs) and UART (in mobile phones and PDAs). On UART Transport Layer, the Bluetooth HCI Protocol can be used between the two UART serial ports which
50、 are on the same PCB board.The system uses UART to transfer data between Bluetooth host and Bluetooth host controller. The UART takes bytes of data and transmits the individual bit in a sequential fashion. At the destination, a second UART re-assembles the bits into complete bytes. Each UART contain
51、s a shift register which is the fundamental method of conversion between serial and parallel forms. Serial transmission of digital information (bits) through a single wire or other medium is much more cost effective than parallel transmission through multiple wires.Usually, the UART does not generat
52、e or receive the external signals used between different items of equipment directly. Separate interface devices are used to convert the logic level signals of the UART to and from the external signaling levels. External signals may be of many different forms. Examples of standards for voltage signa
53、ling are RS-232, RS-422 and RS-485 from the EIA. Historically, the presence or absence of current (in current loops) was used in telegraph circuits. Some signaling schemes do not use electrical wires. Examples of such are optical fiber, IrDA and Bluetooth in its Serial Port Profile (SPP). Some signa
54、ling schemes use modulation of a carrier signal (with or without wires). Examples are modulation of audio signals with phone line modems, RF modulation with data radios, and the DC-LIN for power line communication. The communication may be full duplex or half duplex.In the system, UART uses RS232 in
55、terface parameter configuration, as table II,TABLE II. RS232 INTERFACE PARAMETER CONFIGURATIONBaud rateSpecific infbrniationData bits8ParitynoneStop bit1Flow controlRTS/CTSFlow time3nisUsing RTS/CTS is to avoid that UART buffer overflow. It allows host controller or Bluetooth host to transfer data w
56、hen the value of CTS is 1, and does not when the value is 0. Complete flow time is the max time from setting the value of RTS to 0 to the flow transfer finishing .UART signal line sets Modem mode to null and RS232 in connection status. To RS232, the local TXD is linked with remote RXD and vice versa
57、.UART have the function of correction. It must be reset when the Bluetooth host lost connection with the host controller. Out of sync of RS232 means that HCI packet indicator or HCI packet length is out of the range10. The host controller will send the information of hardware-downtime to Bluetooth h
58、ost, informing the Bluetooth host of error message, if it is out of sync between host controller and Bluetooth host. For resynchronization, the host controller needs accepting a command from Bluetooth host to reset.System Design/wMCd.MLWilFLw nxtwitgluwarHJmyK4IPI1Fig. 1. System hardware designAfter
59、 researching the Bluetooth Protocol, we take the design of the system by using the mode that the Bluetooth module (Bluetooth) connects with the host controller (MCU). In the system, MCU will accept AT commands to control the Bluetooth module on UART.The system design has several technical targets, a
60、s follows,1) Automatic connection modeTo this connection mode, we should pair two Bluetooth-MCU devices which have same hardware structure but different physical addresses in advance. The two devices will connect automatically if they reach the connection distance.FLASH storageA FLASH chip is carrie
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