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at 45 minutes each, to six 90minute episodes. The quick pacing threw off many native viewers, who are accustomed to a more leisurely daytimesoapstyle narrative rhythm. (Chinese TV stations would run two or three episodes every day.) I did not finish the fulllength version and found the truncated one not difficult to follow. What39。t help but sing the folk songs, Nasun says. The vastness of Inner Mongolia and the lack of entertainment options for people living there, made their lives lonely. The nomadic people were very excited about our visits, Nasun recalls. We didn39。每一次鼠標(biāo)信號處理總時(shí)間不大于 1ms,計(jì)算機(jī)自動(dòng)識別無線鼠標(biāo),不需要額外安裝程序,無線鼠標(biāo)移動(dòng)靈活。此時(shí) Shifxa=0需要重新賦值并進(jìn)入下一個(gè)循環(huán)。 //計(jì)算數(shù)據(jù) value_y=temp。 X X2 表示鼠標(biāo)前后移動(dòng)時(shí) (X 方向) 圖像的數(shù)據(jù); Y1 、 Y2 表示鼠標(biāo)左右移動(dòng)時(shí) (Y 方向) 圖像的數(shù)據(jù)。 如圖 22,微控制器通過模擬 SPI 總線與 nRF24L01 連接,控制信號的接收與處理。 無線 模塊的選擇 在幾種短距離無線通信的比較當(dāng)中 ,紅外方案有一定的方向性 ,而藍(lán)牙技術(shù)比較復(fù)雜 ,價(jià)格比較高 ,而無線射頻通信技術(shù)無 論是從系統(tǒng)開銷,電池壽命還是成本方面都占有很大優(yōu)勢 ,同時(shí)它低傳輸速率的特點(diǎn) ,恰恰適合發(fā)送信息量非常小的無線鼠標(biāo)設(shè)計(jì)。最值得一提的它集成了一個(gè) 32級先進(jìn)先出 (FIFO)存儲器管理系統(tǒng),可用于輸出數(shù)據(jù)的緩沖,降低主機(jī)處理器負(fù)荷,并降低整體系統(tǒng)功耗。同時(shí)也避免新收到的數(shù)據(jù)包覆蓋前一個(gè)數(shù)據(jù)包。 關(guān)鍵詞:微加速度計(jì);無線鼠標(biāo);低功耗 目錄 總體結(jié)構(gòu)框圖 ........................................................ 1 系統(tǒng)軟件設(shè)計(jì) ........................................................ 1 方案比較 ............................................................ 3 控制器的選擇 .................................................. 3 微加速度計(jì)選擇 ................................................ 3 無線模塊的選擇 ................................................ 3 二、單元模塊設(shè)計(jì) ............................................................ 4 電路的設(shè)計(jì) .......................................................... 4 遠(yuǎn)端控制子系統(tǒng)硬件電路設(shè)計(jì) .................................... 4 主機(jī)端信號接收系統(tǒng)電路設(shè)計(jì) .................................... 6 軟件的設(shè)計(jì) .......................................................... 6 ADXL345 微加速 度計(jì)模塊程序設(shè)計(jì) ................................ 6 HT82M98A 鼠標(biāo)控制器程序設(shè)計(jì) ................................... 7 nRF24L01 無線模塊程序設(shè)計(jì) ..................................... 7 三、系統(tǒng)調(diào)試 ................................................................ 7 四、設(shè)計(jì)總結(jié) ................................................................ 8 參考文獻(xiàn) .................................................................... 8 附錄 ........................................................................ 8 ................................................ 8 主機(jī)端接收電路原理圖 ................................................. 9 1 一、總體方案設(shè)計(jì) 總體 結(jié)構(gòu)框圖 本系統(tǒng)主要由 無線鼠標(biāo)發(fā)射器、單片機(jī)控制系統(tǒng)、無線鼠標(biāo)接收器和接收系統(tǒng)識別 組成 。 方案二:采用 89C52的優(yōu)點(diǎn) ,且具有 89C52所不具備的一些性能,可不接外部晶振和外部復(fù)位電路,使硬件設(shè)計(jì)更簡單;大容量 2K字節(jié) SRAM;有兩個(gè)獨(dú)立串口;內(nèi)部有 8通道高速 10位 A/D轉(zhuǎn)換器 ,還具有 PWM輸出;總的來說, STC15F2K60S2是一種高速,高可靠性,超低功耗的性能更好的單片機(jī)。 ,超低功耗。接收時(shí),工作電流只有 mA,多種低功率工作模式(掉電模式和空閑模式),使節(jié)能設(shè)計(jì)更方便。 圖 23 按鍵模塊 電路 原理圖 6 主機(jī)端信號接收系統(tǒng)電路 設(shè)計(jì) 無線鼠標(biāo)信號接收電路由無線傳輸模塊 nRF24L0鼠標(biāo)專用通信芯片 HT82M98A、 USB 端口及其他外圍電路組成。因?yàn)?ADXL345 為 16 位數(shù)據(jù)格式,從數(shù)據(jù)寄存器中獲取加速度數(shù)據(jù)后,用戶必須對數(shù)據(jù)進(jìn)行重建。假設(shè)獲取 X 的移動(dòng)值為 50,則光標(biāo)需要移動(dòng) 50個(gè)單位長度,移動(dòng)過程如下: Initialise_state(void)函數(shù)用于初始化狀態(tài)機(jī): Shifxa=positivea。接收方不斷檢測射頻信號,發(fā)現(xiàn)有效數(shù)據(jù)包時(shí),便將其存入接收數(shù)據(jù)緩沖隊(duì)列,并產(chǎn)生中斷,接收完成后,自動(dòng)轉(zhuǎn)入發(fā)送模式,發(fā)送應(yīng)答信號。我們不能學(xué)到后面就忘了前面的知識,更應(yīng)該將所學(xué)的知識緊緊的結(jié)合在一起,綜合運(yùn)用,所謂設(shè)計(jì),就是要求創(chuàng)新,只有將知識綜合運(yùn)用起來才能真正的設(shè)計(jì)好。s performers of the troupe still tour the region39。s essay titled SelfReliance. If you39。 work lives easier, but I simply could not digest the fact that that was my sole purpose in life. With no family to support, I was the sole beneficiary of my employment: the paycheck, the benefits, the incentives and the rewards were mine alone. Not much of a purpose in being selfserving, is there? While I was a student, I felt I was leading a purposeful life. Learning new things, broadening my horizons, expanding my life experiences all gave my life a zip and drive that I had not felt since being in survival mode when my kids were small. After graduating college I felt oddly deflated… but by then, China was on my ho rizon.