【正文】 chool level, a smaller ball is used, but the ball in men39。s Christian Association (YMCA), which later became Springfield College. Naismith (18611939) was a physical education teacher who was seeking a team sport with limited physical contact but a lot of running, jumping, shooting, and the handeye coordination required in handling a ball. The peach baskets he hung as goals gave the sport the name of basketball. His students were excited about the game, and Christmas vacation gave them the chance to tell their friends and people at their local YMCAs about the game. The association leaders wrote to Naismith asking for copies of the rules, and they were published in the Triangle, the school newspaper, on January 15,1892. Naismith39。s ball is in (7274 cm) in circumference. The covering of the ball is leather, rubber, position, or synthetic, although leather covers only are dictated by rules for college play, unless the teams agree otherwise. Orange is the regulation color. At all levels of play, the home team provides the ball. Inflation of the ball is based on the height of the ball39。t e naturally or easily to them, and so they are trying to follow a predetermined set of rules. Some individuals with autism have normal intelligence, and many have special talents in areas such as music or memory. However, individuals with autism may have other mental or emotional problems that coexist with their autism. Some of these other disorders may include impulse control disorders, obsessivepulsive disorder , mood and anxiety disorders, and mental retardation . PSYCHOLOGICAL AND FAMILY FACTORS. Although Henry Maudsley, in the late 1800s, was the first psychiatrist to focus on very young children with mental disorders, it was the psychiatrist Leo Kanner who coined the phrase early infantile autism in 1943. Kanner believed that the parents of children with autistic behaviors were emotionally cold and intellectually distant. He coined the term refrigerator parents to describe them. His belief that parental personality and behavior played a powerful role in the development of autistic behaviors left a devastating legacy of guilt and selfblame among parents of autistic children that continues to this day. Recent studies are unequivocal, however, in demonstrating that parents of autistic children are no different from parents of healthy children in their personalities or parenting behaviors. In fact, many families with an autistic child also have one or more perfectly healthy children. Because autistic children can be extremely sensitive to change, any change within the family situation can be potentially traumatic to the autistic child. A move, divorce, birth of a sibling or other stressors that occur in the lives of most families may evoke a more extreme reaction from an autistic child. While there is no single neurological abnormality found in children with autistic disorders, some research using noninvasive brain imaging 第 25 頁 techniques such as magic resonance imaging (MRI) suggests that certain areas of the brain may be involved. Several of the brain areas being researched are known to control emotion and the expression of emotion. These areas include the temporal lobe (large lobe of each side of the brain that contains a sensory area associated with hearing), the limbic system, the cerebellum, the frontal lobe, the amygdala, and the brain stem, which regulates homeostasis (body temperature and heart rate). Recent research has focused particularly on the temporal lobe because of the finding that previously healthy people who sustain temporal lobe damage may develop autisticlike symptoms. In animal research, when the temporal lobe is damaged, social behavior declines, and restless, repetitive motor behaviors are mon. When measured by MRI, total brain volume appears to be greater for those with autistic disorders. Other neurological factors include lesions to the brain, congenital rubella, undiagnosed and untreated phenylketonuria (PKU), tuberous sclerosis, and Rett39。平時傳感器輸出低電平，當(dāng)有人在探測區(qū)范圍內(nèi)移動時輸出低電平變?yōu)楦唠娖?，此高電平輸入單片機(jī)，作為單片機(jī)的外部觸發(fā)信號處理，經(jīng)單片機(jī)內(nèi)部軟件編程處理后，單片機(jī)輸出控制信號，驅(qū)動聲光報警電路開始報警。 第 19 頁 本設(shè)計所要求達(dá)到的目標(biāo)是在接收到紅外傳感器帶來的低電平信號，可使圖中的綠燈由暗變亮，紅燈產(chǎn)生報警，可觀察到紅燈一閃一閃的。無中斷輸入 ,中斷返回 LN1: SETB CLR CLR 。循環(huán) ,繼續(xù)工作 2. 外部中斷 INTO 服務(wù)程序： PINT0: CLR EX0 。查詢記數(shù)溢出 SJMP L2 L1:MOV TL0 0B0H MOV TH0 3CH DJNZ 51H,L2 。10S 循環(huán)次數(shù) MOV TMOD,01H 。延時消抖 JNB ,ALARM 。指針入口地址 SETB CLR MOV P1,0FFH 。同時，利用中斷方式可以實現(xiàn)報警持續(xù)時間未到 10 秒時，用手工按鍵停止的聲光報警的作用。 第 15 頁 LSSpeakerQ18050R64K7VCC單片機(jī)TXD 圖 10 聲音報警電路 圖 系統(tǒng)硬件電路的選擇及說明 硬件電路的設(shè)計見附圖示， 從以上的分析可知在本設(shè)計中要用到如下器件： AT89C5熱釋電紅外傳感器、 LED、按鍵、反相器 74LS0蜂鳴器等一些單片機(jī)外圍應(yīng)用電路，以及單片機(jī)的手工復(fù)位電路等。如圖 8 示為復(fù)位電路。如圖 7 所示為時鐘電路。該反向放大器可以配置為片內(nèi)振蕩器。驅(qū)動電路將控制信號放大并推動聲光報警設(shè)備完成相應(yīng) 動作。 從設(shè)計的要求來分析該設(shè)計須包含如下結(jié)構(gòu)： 熱釋電紅外傳感探頭電路 、報警電路、單片機(jī)、復(fù)位電路及相關(guān)的控制管理軟件組成；它們之間的構(gòu)成框圖如 圖 4 總體設(shè)計框圖所示： 第 12 頁 圖 4 總 體設(shè)計框圖 處理器采用 51 系列單片機(jī) AT89C51。 就此設(shè)計的核心模塊來說，單片機(jī)就是設(shè)計的中心單元，所以此系統(tǒng)也是單片機(jī)應(yīng)用系統(tǒng)的一種應(yīng)用。 第 11 頁 89C51 的特性像上面都羅列了，它的只讀存儲器即 ROM 是電可擦除的，也稱為FLASHROM， 這就方便了我們的使用 ， 3 方案設(shè)計 總體設(shè)計思路 本設(shè)計包括硬件和軟件設(shè)計兩個部分。在掉電模式下，保存 RAM 的內(nèi)容并且凍結(jié)振蕩器，禁止所用其他芯片功能，直到下一個硬件復(fù)位為止。在芯片擦操作中，代碼陣列全被寫 “1” 且在任何非空存儲字節(jié)被重復(fù)編程以前，該操作必須被執(zhí)行。石晶振蕩和陶瓷振蕩均可采用。 XTAL1：反向振蕩放大器的輸入及內(nèi)部時鐘工作電路的輸入。但在訪問外部數(shù)據(jù)存儲器時，這兩次有效的 /PSEN信號將不出現(xiàn)。如想禁止 ALE 的輸出可在 SFR8EH 地址上置 0。在 FLASH 編程期間，此引腳用于輸入編程脈沖。 P3 口也可作為 AT89C51 的一些特殊功能口，如下表所示： P3 口管腳 備選功能 RXD（串行輸入口） TXD（串行輸出口） INT0（外部中斷 0） INT1（外部中斷 1） T0（記時器 0 外部輸入） T1（記時器 1 外部輸入） WR （外部數(shù)據(jù)存儲器寫選通） RD （外部數(shù)據(jù)存儲器讀選通） P3 口同時為閃爍編程和編程校驗接收一些控制信號。 P2 口在 FLASH編程和校驗時接收高八位地址信號和控制信號。并因此作為輸入時， P2 口的管腳被外部拉低，將輸出電流。 P1 口： P1 口是一個內(nèi)部提供上拉電阻的 8 位雙向 I/O 口， P1 口緩沖器能接收輸出4TTL 門電流。 P0 口： P0 口為一個 8位漏級開路雙向 I/O口，每腳可吸收 8TTL 門電流。采用 40 引腳雙列直插封裝形式。 圖 2 為 AT89C51 單片機(jī)的基本組成功能方塊圖。在傳感器頂端開設(shè)了一個裝有濾