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1、<p><b>  外文資料翻譯</b></p><p>  The 10-bit CMOS ADC (Analog to Digital Converter) is a recycling type device with 8-channel analog inputs. It converts the analog input signal into 10-bit binar

2、y codes at a maximum conversion rate of 500KSPS with 205MHZ A/D converter clock. A/D converter operates with on-chip sample-and-hold function and power down node is supported.</p><p>  The LCD controller in

3、the S3C2440 consists of the logic for transferring LCD image data from a video buffer located in system memory to an external LCD driver.</p><p>  The LCD controller supports monochrome,2-bit per pixel(4-lev

4、el gray scale) or 4-bit per pixel (16-level gray scale) mode on a monochrome LCD,using a time-based dithering algorithm and Frame Rate Control (FRC) method and it can be interfaced with a color LCD panel at 8-bit per p

5、ixel (256-level color) and 12-bit per pixel (4096-level color) for interfacing with STN LCD.</p><p>  The LCD controller can be programmed to support different requirements on the screen related to the numbe

6、r of horizontal and vertical pixels, data line width for the data interface, interface timing and refresh rate.</p><p><b>  FEATURES</b></p><p>  TFT LCD Displays:</p><p&g

7、t;  Supports 1,2,4 or 8-bpp (bit per pixel) palletized color displays for TFT</p><p>  Supports 16,24-bpp non-palletized true-color displays for color TFT</p><p>  Supports maximum 16M color TFT

8、 at 24bit per pixel mode</p><p>  Supports multiple screen size</p><p>  Typical actual screen size: 640 * 480 , 320 * 240 , 160 * 160 , and others</p><p>  Maximum virtual screen s

9、ize is 4Mbytes</p><p>  Maximum virtual screen size in 64K color mode : 2048*1024 and others</p><p>  A/D converter classification:</p><p>  1. The integral type (such as TLC7135)&

10、lt;/p><p>  Integral type AD work principle is the input voltage will convert time (pulse width signal) or frequency (pulse frequency), and then by the timer/counter get digital value. Its advantage is to use a

11、 simple circuit can get high resolution, but shortcomings due to a conversion precision dependent on integral time, so the conversion rate is extremely low. At the early stage of the monolithic AD converter is used mostl

12、y integral type, now compare successive type has gradually become the mainstream.</p><p>  2. Compare two successive type (such as TLC0831)</p><p>  Successive type AD by a comparison is used an

13、d DA converter through successive more logical structure, from the MSB began, in order to every will input voltage and built-in DA converter output carries on the comparison, the n times comparison and the numerical valu

14、e of output. The circuit of the scale to belong to medium. Its advantage is high speed, low power consumption, low resolution (< 12 a) cheap, but high precision (> twelve) price is very high. </p><p> 

15、 3. Parallel comparison of type/parallel comparison type (such as TLC5510)</p><p>  Parallel comparison with multiple comparator type AD, only for a comparison of the conversion, also called flash (fast) typ

16、e. Due to the conversion rate is extremely high, n a conversion to need 2 n-a comparator and, therefore, the size of a circuit, the price is high, only applies to the video AD converter, particularly high speed of the fi

17、eld. String of parallel comparison between parallel structure type AD on the type and successive comparison between type, the most typical is by 2 n/two para</p><p>  4. Σ-Δ modulated (such as AD7705)</p&

18、gt;<p>  Σ-Δ type AD by integrator, comparator, a DA converter and digital filters etc. In principle similar to integral type, the input voltage conversion to time (pulse width) signal, a digital filter to get dig

19、ital value after the treatment. The digital circuit of the single chip basically easily, so easy to do high resolution. Mainly used for audio and measurement. 5. Capacitance array is successive type</p><p> 

20、 Capacitance array type compare successive AD develops in the built-in DA converter capacitance matrix < http://baike.baidu.com/view/10337.htm > way, can also be called charge FenPeiXing again. The general resistor

21、 DA converters most resistance value must be consistent, in a single chip generate high precision of the resistor is not easy. If use capacitance array replace resistor, can be made with low cost high precision monolithi

22、c AD converter. Recent successive type AD converter is mostly for t</p><p>  Pressure frequency conversion type (such as AD650)</p><p>  Pressure Frequency conversion model (Voltage-Frequency Co

23、nverter) is through the indirect conversion way realization of conversion module. Its principle is first the input analog signal conversion into frequency, then use the counter will frequency converted into digital quant

24、ity. In theory this AD resolution can be almost unlimited increase, as long as the sampling time can meet the requirements of the output pulse frequency resolution cumulative number of width. Its advantage is high resolu

25、tio</p><p>  ARM9E-S as an example to introduce the main ARM9 processor structure and characteristics. Its main characteristics as follows: (1) 32 bit fixed-point RISC processors, improved ARM/Thumb code int

26、erweave, enhance sexual on time-multiplier design. Support real-time (real-time) commissioning; (2) in the SRAM of instructions and data, and instructions and data storage capacity of adjustable; (3) in high speed of ins

27、tructions and data buffers (cache) from 4 K bytes capacity to 1 M bytes); (4) set prot</p><p><b>  中文資料翻譯</b></p><p>  10位CMOS ADC (模數(shù)轉(zhuǎn)換器 )是一個(gè)8通道模擬輸入的再循環(huán)類型設(shè)備。器轉(zhuǎn)換模擬輸入信號(hào)為10位二進(jìn)制數(shù)字編碼,最大轉(zhuǎn)

28、換率為2.5MHZ A/D轉(zhuǎn)換器時(shí)鐘下的500KSPS。A/D轉(zhuǎn)換器支持片上采樣 保持功能和掉電 模式的操作 。</p><p>  S3C2440中的LCD控制器由從位于系統(tǒng)存儲(chǔ)器的視頻幀緩沖區(qū)到外部LCD驅(qū)動(dòng)器的轉(zhuǎn)移LCD圖像數(shù)據(jù)邏輯組成。LCD控制器支持單色LCD的單色。2位每像素(4階灰度 )或4位每像素(16階灰度)模式,通過(guò)使用 基于時(shí)間的抖動(dòng)算法和幀頻控制(FRC)方法,其可以連接到8位沒(méi)像素(25

29、6色)的彩色LCD面板和連接到12位每像素(4096色 )的STN LCD.</p><p>  可以編程LCD控制器來(lái)支持不同涉及屏幕水平和垂直像素?cái)?shù),數(shù)據(jù)接口的數(shù)據(jù)線寬度,接口時(shí)序和刷新頻率的需要。</p><p>  TFT LCD顯示:</p><p>  支持 TFT的1、2、4、8bpp(位每像素)調(diào)色顯示 </p><p>  

30、支持彩色TFT的16、24bpp無(wú)調(diào)色顯示</p><p>  支持24位每像素模式下最大16M色TFT</p><p><b>  支持多種屏幕尺寸</b></p><p>  典型實(shí)際屏幕尺寸:640*480、320*240、160*160等</p><p>  最大虛擬屏幕尺寸為4M字節(jié)</p>&l

31、t;p>  64K色模式最大虛擬 屏幕尺寸: 2048*1024等</p><p>  A/D轉(zhuǎn)換器的分類:</p><p>  1.積分型(如TLC7135)</p><p>  積分型AD工作原理是將輸入電壓轉(zhuǎn)換成時(shí)間(脈沖寬度信號(hào))或頻率(脈沖頻率),然后由定時(shí)器/計(jì)數(shù)器獲得數(shù)字值。其優(yōu)點(diǎn)是用簡(jiǎn)單電路就能獲得高分辨率, 但缺點(diǎn)是由于轉(zhuǎn)換精度依賴于積分時(shí)

32、間,因此轉(zhuǎn)換速率極低。初期的單片AD轉(zhuǎn)換器大多采用積分型,現(xiàn)在逐次比較型已逐步成為主流?! ?lt;/p><p>  2.逐次比較型(如TLC0831)</p><p>  逐次比較型AD由一個(gè)比較器和DA轉(zhuǎn)換器通過(guò)逐次比較邏輯構(gòu)成,從MSB開(kāi)始,順序地對(duì)每一位將輸入電壓與內(nèi)置DA轉(zhuǎn)換器輸出進(jìn)行比較,經(jīng)n次比較而輸出 數(shù)字值。其電路規(guī)模屬于中等。其優(yōu)點(diǎn)是速度較高、功耗低,在低分辯率(<1

33、2位)時(shí)價(jià)格便宜,但高精度(>12位)時(shí)價(jià)格很高。  </p><p>  3.并行比較型/串并行比較型(如TLC5510)  </p><p>  并行比較型AD采用多個(gè)比較器,僅作一次比較而實(shí)行轉(zhuǎn)換,又稱flash(快速)型。由于轉(zhuǎn)換速率極高,n位的轉(zhuǎn)換需要2n-1個(gè)比較器,因此電路規(guī)模也極大,價(jià)格也高,只適用于視頻AD轉(zhuǎn)換器等速度特別高的領(lǐng)域。串并行比較型AD結(jié)構(gòu)上介于并行型和

34、逐次比較型之間,最典型的是由2個(gè)n/2位的并行型AD轉(zhuǎn)換器配合DA轉(zhuǎn)換器組成,用兩次比較實(shí)行轉(zhuǎn)換,所以稱為 Half flash(半快速)型。還有分成三步或多步實(shí)現(xiàn)AD轉(zhuǎn)換的叫做分級(jí)(Multistep/Subrangling)型AD,而從轉(zhuǎn)換時(shí)序角度 又可稱為流水線(Pipelined)型AD,現(xiàn)代的分級(jí)型AD中還加入了對(duì)多次轉(zhuǎn)換結(jié)果作數(shù)字運(yùn)算而修正特性等功能。這類AD速度比逐次比較型高,電路 規(guī)模比并行型小?!?lt;/p>

35、<p>  4.Σ-Δ調(diào)制型(如AD7705)  </p><p>  Σ-Δ型AD由積分器、比較器、1位DA轉(zhuǎn)換器和數(shù)字濾波器等組成。原理上近似于積分型,將輸入電壓轉(zhuǎn)換成時(shí)間(脈沖寬度)信號(hào),用數(shù)字濾波器處理后得到數(shù)字值。電路的數(shù)字部分基本上容易單片化,因此容易做到高分辨率。主要用于音頻和測(cè)量。   5.電容陣列逐次比較型</p><p>  電容陣列逐次比較

36、型AD在內(nèi)置DA轉(zhuǎn)換器中采用電容矩陣方式,也可稱為電荷再分配型。一般的電阻陣列DA轉(zhuǎn)換器中多數(shù)電阻的值必須一致,在單芯片上生成高 精度的電阻并不容易。如果用電容陣列取代電阻陣列,可以用低廉成本制成高精度單片AD轉(zhuǎn)換器。最近的逐次比較型AD轉(zhuǎn)換器大多為電容陣列式的。 </p><p>  壓頻變換型(如AD650)  </p><p>  壓頻變換型(Voltage-Frequency Co

37、nverter)是通過(guò)間接轉(zhuǎn)換方式實(shí)現(xiàn)模數(shù)轉(zhuǎn)換的。其原理是首先將輸入的模擬信號(hào)轉(zhuǎn)換成頻率,然后用計(jì)數(shù)器將頻率轉(zhuǎn)換成數(shù)字量。從理論上講這種AD的分辨率幾乎可以無(wú)限增加,只要采樣的時(shí)間能夠滿足輸出頻率分辨率要求的累積脈沖個(gè)數(shù)的寬度。其優(yōu)點(diǎn)是分辯率高、功耗低、價(jià)格低,但是需要外部計(jì)數(shù)電路共同完成AD轉(zhuǎn)換。</p><p>  以ARM9E-S為例介紹ARM9處理器的主要結(jié)構(gòu)及其特點(diǎn)。其主要特點(diǎn)如下:(1)32bit定點(diǎn)

38、RISC處理器,改進(jìn)型ARM/Thumb代碼交織,增強(qiáng)性乘法器設(shè)計(jì)。支持實(shí)時(shí)(real-time)調(diào)試;(2)片內(nèi)指令和數(shù)據(jù)SRAM,而且指令和數(shù)據(jù)的存儲(chǔ)器容量可調(diào);(3)片內(nèi)指令和數(shù)據(jù)高速緩沖器(cache)容量從4K字節(jié)到1M字節(jié);(4)設(shè)置保護(hù)單元(protection unit),非常適合嵌入式應(yīng)用中對(duì)存儲(chǔ)器進(jìn)行分段和保護(hù);(5)采用AMBA AHB總線接口,為外設(shè)提供統(tǒng)一的地址和數(shù)據(jù)總線;(6)支持外部協(xié)處理器,指令和數(shù)據(jù)總線

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