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1、<p><b>  中文3464字</b></p><p>  畢業(yè)設(shè)計外文資料翻譯</p><p>  題 目 基于MSP430F149單片機的時 </p><p>  鐘設(shè)計 </p><p>  專 業(yè) 機械設(shè)計制造及其自動化 </p&

2、gt;<p>  班 級 機械1102班 </p><p>  學(xué) 生 </p><p>  學(xué) 號 </p><p>  指導(dǎo)教師

3、 </p><p>  二〇一 五 年 三 月 九日</p><p>  SmartGrid,2013,3,91-95doi:10.12677/sg.2013.33016</p><p>  Published Online June 2013</p><p>  Based on MSP430F149 SCM smalles

4、t system design and application</p><p><b>  By</b></p><p><b>  AE Tuuml</b></p><p>  Department of Mechanical and Electronic Engineering, College China Unive

5、rsity of Geosciences, </p><p><b>  430200</b></p><p><b>  Abstract:</b></p><p>  Single chip microcomputer minimum system, or the minimum application system,

6、 refers to the element with the least amount of single-chip microcomputer system can work. For the single chip MSP430 series Machine, the smallest system generally includes: single chip microcomputer, the power supply mo

7、dule, crystal vibration module, reset circuit module, JTAG interface circuit. This paper introduces the MSP430F149 single the characteristics of the machine and the minimum system based on MSP430F149 MCU </p><

8、p>  Keywords: MSP430; smallest system; circuit design; simulation; test</p><p>  Based on MSP430F149 SCM smallest system design and application</p><p>  Introduction</p><p>  Wit

9、h the rapid development of modern electronic technology and computer technology, microcontroller technology has penetrated into every aspect of human life, in automation, intelligent instrumentation, process control and

10、increasing use of household appliances and many other fields, microcontroller family is becoming more and more big, more and more varieties, and in technology have distinguishing feature each, Texas instruments (TI) new

11、MSP430F149 Single-chip low power consumption, powerful, f</p><p>  Single-chip microcomputer with necessary external device, generally including power supply into the power switch, reset circuit, crystals, i

12、nput and output circuit can constitute a minimum system, such as simple structure</p><p>  MSP430F149 chip has 60 KB FLASH + 256 bytes, 2 karma, including the basic clock module, the watchdog timer, with thr

13、ee capture/compare registers and PWM output 16-bit timers, with seven capture/compare registers and PWM output, two 16 bit timer interrupt function of 8 bits parallel port, four 8-bit parallel port, analog comparator, 12

14、 bit A/D converter, and the two serial communication interface module, etc. MSP430F149 chip has the following characteristics:(1) Low power consumption, voltage of </p><p>  6 mu s; (9) ESD protection, stron

15、g anti-interference; (10) fan running environment temperature - 40 ~ + 85 ℃, suitable for the industrial environment.</p><p>  Of all peripheral modules MSP430 series MCU control is achieved through special

16、registers, so it is relatively easy to write. When programming development through the special programmer, you can choose to assembly or C language programming, IAR for MSP430 series MCU development the company dedicated

17、 C430 languages, can directly by the WORKBENCH and C - SPY compiler debugging, using flexible and simple.</p><p>  1 The minimum system design</p><p>  Minimum system is a necessary to ensure re

18、liable processors work of basic circuit, including power supply module, the module of crystal vibration and reset circuit module, JTAG interface circuit, display module, etc</p><p>  1.1 The power supply mod

19、ule</p><p>  This system need to use the + 5 V and + 3.3 V dc regulated power supply; including MSP430Fl49 and some peripheral devices need to + 3.3 V power supply, the other part need to + 5 V power supply.

20、 In this system, in order to + 5 V dc voltage for the input voltage, 3.3 V + linear step-down directly by the + 5 V.</p><p>  1.2 Crystal vibration module</p><p>  MSP430 series MCU clock module

21、 includes numerical control oscillator (DCO), high-Speed of crystal oscillator and crystal oscillator at low speed clock source. This is to understand System of rapid processing data and low power requirements of contrad

22、iction, through the design multiple clock source or for clock design all sorts of different working mode, can solve some Peripheral parts clock requirements of real-time applications, such as low frequency communication,

23、 LCD display, timing Device, c</p><p>  Low-speed crystal oscillator (L X F T L) can meet the requirements of low power consumption and the use of 32.768 kHz crystal vibration. Default LFXTL oscillator work

24、in low frequency mode, the 32.768 kHz, but can be by external 450 kHz ~ 8 MHZ crystal vibration at a high speed Oscillation device or ceramic resonator working in high frequency mode, in this system using low frequency m

25、ode Type, crystals external 2 33 PF capacitor after XIN and XOUT connected to the MCU. High-speed chip, also know</p><p>  1.3 Reset circuit module</p><p>  Manual reset is minimal systems commo

26、nly used functions, this system adopts the manual reset button switches and RC circuit implementation, the circuit structure is simple.</p><p>  1.4 The JTAG interface circuit</p><p>  JTAG tech

27、nology is a kind of embedded debugging technology, chip internal encapsulates the special electrical test TAP (test access port), through special JTAG test tools to test and control of internal nodes, At present most of

28、the ARM device support JTAG protocol, standard JTAG interface is 4 line; TMS (test mode selection), TCK (the clock) and TDI (test data serial input), TDO serial output (test data). JTAG interface connection there are two

29、 standards that 14 needle JTAG interface MC9328MX1 </p><p>  2 Application circuit design based on minimum system</p><p>  2.1 digital tube display module</p><p>  A digital tube di

30、splay need 74 hc164 drive, 74 hc164 serial input and parallel output. Its parallel output actually there is a delay, just delay time is small, can be considered as parallel output. Here is the way a serial port 0, 0 is a

31、nd communication of the shift register. TXD, RXD at this time is not like other ways a send, a receiver, but RXD can also input, output TXD shift pulse. Sending and receiving data must be 8, bit rate fixed is 1/12 of the

32、 crystals. When set mode 0, it is automatic</p><p>  Receiving process: REN first to buy 1, then 1 TXD, read RXD condition, high level will receive 1, receive low level 0; Then pull down the TXD, after a sli

33、ght delay TXD again high, read RXD, high level will receive 1, low level 0, and so on. Read until 8 bits. Send SBUF process: is sent automatically. Send 1 RXD high first, TXD again get higher; And TXD become low, send 0

34、RXD lower first, TXD again get higher; Then the TXD become low, and so on. This process is done automatically, need not specia</p><p>  2.2 The LED display module</p><p>  Pick up a few LED thro

35、ugh the I/O port, through the programming a simple program, which can realize the LED flashing, so as to achieve the test circuit and chip is normal.</p><p>  2.3 D/A conversion module</p><p>  

36、MSP430F149 MCU with 12 bit A/D converter, but no D/A conversion, need external D/A conversion circuit. So choose DAC0832 d/a conversion chip, and UA741 high-gain general amplifier composed of d/a conversion circuit opera

37、tion. UA741 chip pins as shown in figure 1.</p><p>  DAC0832 is 8 of D/A conversion chip. Complete compatible with microprocessor. The DA chip with its low cost, simple interface, convert the advantages of e

38、asy control, widely used in the MCU application system. D/A converter by eight input latch, 8-bit DAC registers, 8 D/A conversion circuit and control circuit. DAC0832 is sampling frequency for 8 D/A conversion chip, Inte

39、grated circuit has two levels of input register, DAC0832 chip with double buffer, single buffer and through three kinds of inp</p><p>  2.4 LCD display module</p><p>  A/D conversion output data

40、, need to use the LCD display.</p><p>  2.5 Eight independent type keyboard module</p><p>  The keyboard in the microcomputer application system, realize the function of the input data, transmit

41、 command, and is a major means of human intervention. Keyboard with coding and non coding keyboard, independent type button structure, matrix structure key. First, monitoring any key press, the key of closed or not, refl

42、ect on the voltage is present a high level or low level, so through the detection level of high and low status, can confirm button pressed or not. Second, determine which key is </p><p>  2.6 The software de

43、sign</p><p>  Using the IAR Embedded Workbench Evaluation for MSP4305.10.1 software programming, the basic idea: the LED lights, digital tube as the main program, the 7 key as interrupt, LCD is used to enter

44、 the interrupt and A/D conversion output display output.</p><p>  2.7 extensions</p><p>  By extending the mouth can facilitate the single-chip microcomputer and peripheral module, resources, ma

45、ke full use of the chip pin real MSP430 single chip microcomputer powerful function into full play. Loading other modules in the extension mouth, through debugging, testing can produce a corresponding products on the mar

46、ket, strong practicability and wide prospect of market. Load on minimum system for example, a pressure sensor, electronic scale, what you can accomplish through programming, do</p><p>  3 Conclusions</p&g

47、t;<p>  Minimum system can directly as a core component used in the engineering and scientific research, has good versatility and expansibility. On the basis of the minimum system, can be easily to carry on the se

48、condary development and function extension, can shorten the development cycle, and reduce development costs. This paper realized the basic function of the minimum system, each module of hardware circuit is introduced. An

49、d on this basis to build a simple application platform. The minimum system </p><p>  References:</p><p>  [1] Cao lei. MSP430 microcontroller C program design and practice [M]. Beijing Universit

50、y of aeronautics and astronautics Press, 2007:105-2007.</p><p>  [2] Xiao Xing gong, strong bum then asked xiong-ying wu. MSP430 single chip microcomputer based and practice [M].Beijing University of aeronau

51、tics and astronautics press, 2008:84-85.</p><p>  [3] Texas Instrument, MSP430x14xFamilyUser’sGuide[S].2003.(http://www.ti.com.).</p><p>  [4] jian-hua shen. MSP430 series 16 ultra-low power MCU

52、 principle and practice [M]. Beijing University of aeronautics and astronautics press, 2008:202-202. The Modern Construction of Modern Construction.</p><p>  SmartGrid,2013,3,91-95doi:10.12677/sg.2013.33016&

53、lt;/p><p>  Published Online June 2013</p><p>  基于MSP430F149單片機的最小系統(tǒng)設(shè)計及其應(yīng)用</p><p><b>  AE Tuuml</b></p><p>  Department of Mechanical and Electronic Engineerin

54、g, College </p><p>  China University of Geosciences, 430200</p><p>  摘 要 : 單片機最小系統(tǒng),或稱為最小應(yīng)用系統(tǒng),是指用最少的元件組成的單片機可以工作的系統(tǒng)。對于MSP430系列單片機來說,最小系統(tǒng)一般包括:單片機,電源模塊,晶振模塊,復(fù)位電路模塊,JTAG接口電路。本文介紹了MSP430F149單片機的特點及

55、基于MSP430F149單片機的最小系統(tǒng)設(shè)計及其應(yīng)用,并介紹了各模塊的組成及功能。包括數(shù)碼管顯示模塊,LED燈顯示模塊,LCD液晶顯示模塊,8位獨立鍵盤等電路模塊及擴展應(yīng)用。該最小系統(tǒng)可進行在線下載,仿真和調(diào)試,經(jīng)實驗證明原理正確可靠,可以廣泛應(yīng)用于教學(xué),科研和電子設(shè)計領(lǐng)域。通過加載相應(yīng)模塊可以制作成實用的產(chǎn)品,具有很大的實用性。</p><p>  關(guān)鍵詞 MSP430;最小系統(tǒng);電路設(shè)計;仿真;調(diào)試<

56、/p><p>  隨著現(xiàn)代電子技術(shù)和計算機技術(shù)的飛速發(fā)展,單片機技術(shù)已經(jīng)滲透到人類生活的各個方面,在自動化裝置、智能化儀器儀表、過程控制和家用電器等許多領(lǐng)域得到日益廣泛的應(yīng)用, 單片機家族也越來越龐大,品種越來越多,且在技術(shù)上各有特色, 美國德州儀器公司(TI公司)新推出的MSP430F149單片機功耗低, 功能強大, 為廣大硬件設(shè)計師所青睞。單片機芯片配以必要的外部器件,一般包括電源供入及電源開關(guān)、復(fù)位電路、晶振、

57、輸入輸出電路等就能構(gòu)成最小系統(tǒng),結(jié)構(gòu)簡單。MSP430F149芯片有60KB+256字節(jié)FLASH,2KBRAM,包括基本時鐘模塊、看門狗定時器、帶3個捕獲/比較寄存器和PWM輸出的16位定時器、帶7個捕獲/比較寄存器和PWM輸出的16位定時器、2個具有中斷功能的8位并行端口、4個8位并行端口、模擬比較器、12位A/D轉(zhuǎn)換器、2個串行通信接口等模塊。MSP430F149芯片具有如下特點: (1)功耗低:電壓2.2V、時鐘頻率1MHz時,

58、活動模式芯片電流為200μA,關(guān)閉模式時電流僅為0.1A;(2)高效16位RISC-CPU,27條指令,8MHz時鐘頻率時,指令周期時間為125ns,絕大多數(shù)</p><p>  1 最小系統(tǒng)系統(tǒng)設(shè)計</p><p>  最小系統(tǒng)是由保證處理器可靠工作所必須的基本電路組成的,主要包括電源模塊、晶振模塊、復(fù)位電路模塊、JTAG接口電路、顯示模塊等組成</p><p>

59、<b>  1.1電源模塊</b></p><p>  本系統(tǒng)需要使用+5V和+3.3V的直流穩(wěn)壓電源,其中MSP430Fl49及部分外圍器件需要+3.3V電源,另外部分需要+5V電源。在本系統(tǒng)中,以+5V直流電壓為輸入電壓,+3.3V由+5V直接線性降壓。</p><p><b>  1.2 晶振模塊</b></p><p&

60、gt;  MSP430系列單片機時鐘模塊包括數(shù)控振蕩器(DCO)、高速晶體振蕩器和低速晶體振蕩器等3個時鐘源。這是為了解決系統(tǒng)的快速處理數(shù)據(jù)要求和低功耗要求的矛盾,通過設(shè)計多個時鐘源或為時鐘設(shè)計各種不同工作模式,才能解決某些外圍部件實時應(yīng)用的時鐘要求,如低頻通信、LCD顯示、定時器、計數(shù)器等。數(shù)字控制振蕩器DCO已經(jīng)集成在MSP430內(nèi)部,在系統(tǒng)中只需設(shè)計高速晶體振蕩器和低速晶體振蕩器兩部分電路。</p><p>

61、;  低速晶體振蕩器( L F X T l ) 滿足了低功耗及使用32.768kHz晶振的要求。LFXTl振蕩器默認(rèn)工作在低頻模式,即32.768kHz,也可以通過外接450kHz~8MHz的高速晶體振蕩器或陶瓷諧振器工作在高頻模式,在本系統(tǒng)中使用低頻模式,晶振外接2個33pF的電容經(jīng)過XIN和XOUT連接到MCU。</p><p>  高速晶振也稱為第二振蕩器XT2,它為MSP430F149工作在高頻模式時提供

62、時鐘,XT2最高可達8MHz。在系統(tǒng)中XT2采用4MHz的晶體,XT2外接2個33pF的電容經(jīng)過XT2IN和XT2OUT連接到MCU。</p><p>  1.3 復(fù)位電路模塊</p><p>  手動復(fù)位是最小系統(tǒng)常用的功能,本系統(tǒng)采用按鍵開關(guān)和RC組合電路實現(xiàn)手動復(fù)位,電路結(jié)構(gòu)簡單。</p><p>  1.4 JTAG接口電路</p><p

63、>  JTAG技術(shù)是一種嵌入式調(diào)試技術(shù),芯片內(nèi)部封裝了專門的測試電路TAP(測試訪問口),通過專用的JTAG測試工具對內(nèi)部節(jié)點進行測試和控制,目前大多數(shù)ARM器件支持JTAG協(xié)議,標(biāo)準(zhǔn)JTAG接口是4線;TMS(測試模式選擇)、TCK(測試時鐘)、TDI(測試數(shù)據(jù)串行輸入)、TDO(測試數(shù)據(jù)串行輸出)。JTAG接口的連接有兩種標(biāo)準(zhǔn),即14針JTAG接口與MC9328MX1連接電路。這里使用的是由74HC244D三態(tài)輸出的八路緩沖器

64、組成的14針JTAG接口電路。</p><p>  2 基于最小系統(tǒng)應(yīng)用電路設(shè)計</p><p>  2.1 數(shù)碼管顯示模塊</p><p>  位數(shù)碼管顯示需要74HC164驅(qū)動,74HC164是串行輸入,并行輸出的。它的并行輸出其實是有延時的,只是延時時間小,可以認(rèn)為是并行輸出。這里用的是串口的方式0,方式0是和移位寄存器通訊的。此時TXD、RXD不是像別的方式

65、那樣一個發(fā)送,一個接收,而是RXD既可輸出也可輸入,TXD作移位脈沖。收發(fā)數(shù)據(jù)必須是8位,比特率固定是晶振的1/12。當(dāng)設(shè)置方式0后,它就自動把TXD作移位脈沖了。在TXD高電平時檢測RXD,若是高電平,74HC164就讀進1,若是低電平,就讀進0。</p><p>  接收的過程:先給REN置1,然后TXD置1,讀RXD狀態(tài),高電平就接收1,低電平接收0;然后拉低TXD,略微延時后TXD再置高,讀RXD,高電平

66、就接收1,低電平接收0,以此類推。直到讀完8個位。然后RI變高。發(fā)送過程:給SBUF寫進一個數(shù),就自動發(fā)送。發(fā)送1時RXD先變高,TXD再變高;然后TXD變低,發(fā)送0時RXD先變低,TXD再變高;然后TXD變低,以此類推。上述過程都是自動完成的,不用專門編程。</p><p>  數(shù)碼管從正面看,小數(shù)點在右下腳,上面的引腳從左向右分別是F、G公共端A、B下面的引腳從左向右分別是E、D公共端 C、Dp(小數(shù)點)。&

67、lt;/p><p>  2.2 LED顯示模塊</p><p>  從I/O口接幾個LED,通過編程一個簡單的程序,可實現(xiàn)LED燈閃爍,從而達</p><p>  到檢驗電路及芯片是否正常。</p><p>  2.3 D/A轉(zhuǎn)換模塊</p><p>  MSP430F149單片機自帶12位A/D轉(zhuǎn)換器,但沒有D/A轉(zhuǎn)換,

68、需要外接D/A轉(zhuǎn)換電路。因此選用DAC0832數(shù)模轉(zhuǎn)換芯片,及UA741高增益運算通用放大器組成的數(shù)模轉(zhuǎn)換電路。UA741芯片引腳如圖所示。</p><p>  DAC0832是8分辨率的D/A轉(zhuǎn)換集成芯片。與微處理器完全兼容。這個DA芯片以其價格低廉、接口簡單、轉(zhuǎn)換控制容易等優(yōu)點,在單片機應(yīng)用系統(tǒng)中得到廣泛的應(yīng)用。D/A轉(zhuǎn)換器由8位輸入鎖存器、8位DAC寄存器、8位D/A轉(zhuǎn)換電路及轉(zhuǎn)換控制電路構(gòu)成。</p

69、><p>  DAC0832是采樣頻率為八位的D/A轉(zhuǎn)換芯片,集成電路內(nèi)有兩級輸入寄存器,使DAC0832芯片具備雙緩沖、單緩沖和直通三種輸入方式,以便適于各種電路的需要(如要求多路D/A異步輸入、同步轉(zhuǎn)換等)。這8位D/A轉(zhuǎn)換器有8個輸入端(其</p><p>  中每個輸入端是8位二進制數(shù)的一位),有一個模擬輸出端。輸入可有28=256個不同的二進制組態(tài),輸出為256個電壓之一,即輸出電壓

70、不是整個電壓范圍內(nèi)任意值,而只能是256個可能值。</p><p>  2.4 LCD顯示模塊</p><p>  A/D轉(zhuǎn)換輸出數(shù)據(jù),需要用LCD顯示。控制器內(nèi)部帶有80×8位(80字節(jié))的RAM緩沖區(qū)。</p><p>  2.5 八位獨立式鍵盤模塊</p><p>  鍵盤在單片機應(yīng)用系統(tǒng)中,實現(xiàn)輸入數(shù)據(jù)、傳送命令的功能,是人

71、工干預(yù)的主要手段。鍵盤有編碼鍵盤和非編碼鍵盤,獨立式按鍵結(jié)構(gòu),矩陣式按鍵結(jié)構(gòu)。幾種方式各有千秋,這里我們使用的是8位獨立式鍵盤。編碼鍵盤的鍵輸入程序完成三個基本任務(wù):首先,監(jiān)測有無鍵按下,鍵的閉合與否,反映在電壓上就是呈現(xiàn)出高電平或低電平,所以通過電平的高低狀態(tài)的檢測,便可確認(rèn)按鍵按下與否。其次,判斷是哪個鍵按下。最后,完成鍵處理任務(wù)。其中軟件編程使用的是中斷掃描方式。</p><p>  鍵盤電路中使用的74H

72、C2是一個高速Si-gate CMOS1集成芯片,其引腳低功耗兼容。屬于肖特基TTL(輸入通道)。該74HC21提供4-input與功能。</p><p><b>  2.6 軟件設(shè)計</b></p><p>  使用IAR Embedded Workbench Evaluation for MSP4305.10.1軟件編程,基本思想:把LED燈,數(shù)碼管作為主程序,7

73、號鍵作為中斷,LCD用來進入中斷和A/D轉(zhuǎn)化后輸出顯示輸出。</p><p><b>  2.7 擴展應(yīng)用</b></p><p>  通過擴展口可以方便單片機與外圍模塊相連,充分利用芯片引腳資源,真正發(fā)揮MSP430單片機強大的功能。在擴展口上加載其他模塊,通過調(diào)試、測試,可以生產(chǎn)出相應(yīng)產(chǎn)品投放市場,實用性強,市場前景廣闊。譬如,在最小系統(tǒng)上加載一個壓力傳感器,再通

74、過編程、下載就可以做成電子秤,由于系統(tǒng)的功耗低,可以做成便攜式,給人們的生活帶來很大的方便;在最小系統(tǒng)的基礎(chǔ)上加載一個高精度的超聲波測距模塊,同樣,通過編程、下載就可以做成電子尺,從而取代傳統(tǒng)的卷尺,可以彌補卷尺的一些缺點;如果加上揚聲器,編程下載,把整個系統(tǒng)封裝成模塊,可以應(yīng)用到汽車上,當(dāng)車在行駛過程中車距小于某一距離時,通過發(fā)聲提醒駕駛員請保持車距等其他相關(guān)應(yīng)用。</p><p><b>  3 結(jié)

75、束語</b></p><p>  最小系統(tǒng)可以直接作為核心部件應(yīng)用于工程和科研中,具有良好的通用性和可擴展性。在最小系統(tǒng)的基礎(chǔ)上,可以很方便地進行二次開發(fā)和功能擴展,能夠縮短開發(fā)周期,降低開發(fā)成本。本文實現(xiàn)了最小系統(tǒng)的基本功能,介紹了各模塊的硬件電路。并在此基礎(chǔ)上搭建了簡單的應(yīng)用平臺。該最小系統(tǒng)可以作為學(xué)習(xí)、實踐教學(xué)實驗板用。也可經(jīng)過適當(dāng)修、計算機教學(xué)與科研、工業(yè)控制等領(lǐng)域,還可以通過加載相應(yīng)模塊,改

76、裝成實用的產(chǎn)品,投入市場。</p><p><b>  參考文獻:</b></p><p>  [1] Cao lei. MSP430 microcontroller C program design and practice [M]. Beijing University of aeronautics and astronautics Press, 2007:105

77、-2007.</p><p>  [2] Xiao Xing gong, strong bum then asked xiong-ying wu. MSP430 single chip microcomputer based and practice [M].Beijing University of aeronautics and astronautics press, 2008:84-85.</p>

78、;<p>  [3] Texas Instrument, MSP430x14xFamilyUser’sGuide[S].2003.(http://www.ti.com.).</p><p>  [4] jian-hua shen. MSP430 series 16 ultra-low power MCU principle and practice [M]. Beijing University o

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