【正文】 無線傳輸模塊在無線傳輸模塊部分，PC機(或其他外部設(shè)備)有數(shù)據(jù)傳輸或需設(shè)置設(shè)備參數(shù)時，通過串口將數(shù)據(jù)發(fā)送給單片機，單片機在接收數(shù)據(jù)后，將需發(fā)送的數(shù)據(jù)(包括目標設(shè)備地址和所要發(fā)送的數(shù)據(jù))又通過SPI接口發(fā)送給nRF905，nRF905給數(shù)據(jù)加前導碼和CRC碼，將數(shù)據(jù)包發(fā)送。當最高2位中有1個為0時，作為當前放音操作的起始地址。錄放音的操作采用的是M6模式，在M6模式下，/EOM作為操作指示信號，當錄音或放音操作時，該引腳輸出高電平，在暫?；蛲Ｖ共僮鲿r，該引腳輸出低電平。當放音時，根據(jù)需播放的語音內(nèi)容，單片機找到相應(yīng)的語音段起始地址，并通過口線送出。通過改變各相通電的次序可以調(diào)整步進電機的運轉(zhuǎn)方向。 P5口作為帶鎖存器的并行輸出口，CPU通過P5送出步進電機的四相驅(qū)動信號STEPA、STEPB、STEPC、STEPD，～，輸出線為低時，對應(yīng)的相線通電。③ 通過改變每步的延時時間來控制步進電機的速度調(diào)節(jié)。③ 所賦的初值不能過小，否則 D/A 的輸出不足以驅(qū)動開關(guān)管 Q1 的導通，致使直流電機不旋轉(zhuǎn)。對特定的具體設(shè)計，主要問題是按照系統(tǒng)功能合理組織按鍵的組成。b 鍵識別，以確定閉合鍵的行列位置。但具體那些由硬件完成由軟件完成，要看接口電路的情況。經(jīng)過幾個月的努力，核心問題已經(jīng)全部解決，所有功能已基本實現(xiàn)，只是在通用性上還有待提高。由于受時間限制，整個實驗箱的制作與完成都比較倉促，另外有的器件很不好找，所以實驗箱在功能實現(xiàn)方面還有點欠缺。相信經(jīng)過不斷的完善，現(xiàn)代高端數(shù)字實驗箱能成為學校單片機實驗的主體設(shè)備。劉老師在大局上指導我畢業(yè)設(shè)計的每一進程。在此表示衷心的感謝和崇高的敬意！在此，我還要非常感謝同組的王彪、王博同學以及胡建明老師。由于我是初次擔負這樣的設(shè)計調(diào)試任務(wù)，所以在設(shè)計思路和實現(xiàn)功能上難免有些不足之處，希望各位老師能夠批評指正。C to +85186。A Istbydclk Supply current in standby, uCLK enabled 2) 181。42 177。A StandBy 12OFF 27181。A StandBy 8 125181。A StandBy 41 130181。A StandBy 201 170181。A StandBy 202 210181。A StandBy 164 285181。s nRF905 is monitoring the air for ining munication. 3. When the nRF905 senses a carrier at the receiving frequency, Carrier Detect (CD) pin is set high. 4. When a valid address is received, Address Match (AM) pin is set high. 5. When a valid packet has been received (correct CRC found), nRF905 removes the preamble, address and CRC bits, and the Data Ready (DR) pin is set high. 6. MCU sets the TRX_CE low to enter standby mode (low current mode). 7. MCU can clock out the payload data at a suitable rate via the SPI interface. 8. When all payload data is retrieved, nRF905 sets Data Ready (DR) and Address Match (AM) low again. 9. The chip is now ready for entering ShockBurst ?RX, ShockBurst ?TX or power down mode. If TX_EN is set high while TRX_CE is kept high, the nRF905 would enter ShockBurst?TX and start a transmission according to the present contents in the SPIregisters. If TRX_CE or TX_EN is changed during an ining packet, the nRF905 changes mode immediately and the packet is lost. However, if the MCU is sensing the Address Match (AM) pin, it knows when the chip is receiving an ining packet and can therefore decide whether to wait for the Data Ready (DR) signal or enter a different mode. To avoid spurious address matches it is remended 。A Rx433 16OFF Rx868/915 16OFF Ma Reduced Rx 16OFF mA Tx 10dBm 16OFF 30 mA Tx 6dBm 16OFF 20 mA Tx 2dBm 16OFF 14 mA Tx 1dBm 16OFF 11 mA Conditions: VDD = , VSS = 0V, TA = 27186。A StandBy 84 275181。A StandBy 82 185181。A StandBy 121 150181。A StandBy 16 135181。A StandBy 20OFF 46181。58 KHZ RGFSK Data rate 100 KBPS fCH433 Channel spacing for 433MHz band 100 KHZ fCH868/915 Channel spacing for 868/915MHz band 200 KHZ Transmitter operation PRF10 Output power 10dBm setting6) 7 10 11 dBm PRF6 Output power 6dBm setting6) 3 6 9 dBm PRF2 Output power –2dBm setting6) 6 2 2 dBm PRF10 Output power 10dBm setting 6) 14 10 6 dBm PBW 20dB bandwidth for modulated carrier 190 KHZ ITX10dBm Supply current 10dBm output power 30mA ITX10dBmSupply current 10dBm output power 11mAReceiver operationIRX Supply current in receive mode mA RXSENS Sensitivity at %BER 100 dBm RXMAX Maximum received signal 0 dBm C/ICO C/I Cochannel 8) 13 dB C/I1ST Blocking at ＋10MHz 8) 7 dB C/I2ND Blocking at 10MHz 8) 16 dB C/I1M Image rejection 8) 30 dB 1) Max value determined by design and characterization testing. 2) Output frequency is 4MHz load of external clock pin is 5pF, Crystal is 4MHz. 3) Crystal is 4MHz. 4) Pin voltages are VSS or VDD. 5) Chip in power down, SPI_SCK frequency is 1MHz. 6) Operates in the 433, 868 and 915 MHz ISM band. 7) The crystal frequency may be chosen from 5 different values (4, 8, 12, 16, and 20MHz) 8) Data is Manchesterencoded before GFSK modulatio n. 9) Optimum load impedance, please see peripheral RF information. 10) Channel width and channel spacing is 200kHz. CURRENT CONSUMPTION Table 4 nRF905 current consumption. MODECRYSYALFREQ.[MHZ]OUTPUTCLOCKFREQ. [MHZ]TYPICAL CURRENTPowerDown 16OFF StandBy 4OFF 12181。A ISPI Supply current in SPI programming 3) 20 181。C) Table 3 nRF905 electrical specifications.SymbolParameter(condition)NotesMin.Typ.Max.Operating conditions VDD Supply voltage V TEMP Operating temperature 40 27 +85 176。2002．145～152.[3] :中國電力出版社,～20.[4]黃智偉，：電子工業(yè)出版社，～192.[5] :北京理工大學出版社,2001. 92～94.[6] 何立明．單片機高級教程——應(yīng)用與設(shè)計，北京：北京航天航空大學出版社，～173．[7]康華光，陳大欽. 電子技術(shù)基礎(chǔ)—數(shù)字部分. 北京：高等教育出版社，2000. 29～31.[8] 吳景狄．，2001(4):30～31．[9] 求是科技. :人民郵電出版社,～91.[10] 劉光潭．中外集成電路簡明速察手冊，上海：電子工業(yè)出版社，1991．45～46.[11]李忠杰．步進 電動機應(yīng)用技術(shù)[M]．北京：機械 工業(yè) 出版社，～25.[12]劉瑞新，趙全利，趙建軍等．單片機原理及應(yīng)用教程，北京：機械工業(yè)出版社，2003年7月，157～164．[13] 李光飛，：北京航空航天大學出版社,2004. 13～20.[14]張俊謨. MCS51和80C51系列單片機. 電子世界，2001年，第8期，30～38.[15] 李廣弟，朱月秀，王秀山．單片機基礎(chǔ)（修訂版），北京：北京航空航天大學出版社，2001年，16～17．[16]譚博學，苗匯靜等．集及成電路原理應(yīng)用．電子工業(yè)出版社，2003．29～31.[17]AT89C51，AT89C52說明書[S] ATMEL公司提供[18]ISD Inc．ISD data book．April 1998 [19]Wind River System Inc．VxWorks NetWork Programmer’sGuide[Z] [20]Single chip 433／868／915MHz Transceiver nRF905．Nordic VLSI ASA．2004．1．附錄一：各模塊原理圖附錄二：實驗箱PCB圖附錄三：英文資料Single chip 433/868/915 MHz Transceiver nRF905 FEATURES ? True single chip GFSK transceiver in a small 32pin package (32L QFN 5x5mm) ? ShockBurst? mode for low power operation ? Power supply range to V ? Multi channel operation – ETSI/FCC Compatible ? Channel switching time 650us ? Extremely low cost Bill of Material (BOM) ? No external SAW filter ? Adjustable output power