【正文】 ren of the feelings in a period, but was eventually infarction when graduation party in the throat, later again stood on the pitch he has sweat profusely, looked at his thrown a basketball hoops, suddenly found himself has already can39。那些曾經(jīng)所謂的非做不可，只是青蔥年華里自己給自己注射的一支強心劑，或者說，是自以為是的精神寄托罷了。ll be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. It will be like he is 單片機原理及系統(tǒng)課程設計報告 17 diving into the shallow end. Skydiver preps for the big jump When he jumps, he is expected to reach the speed of sound 690 mph (1,110 kph) in less than 40 seconds. Like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him pletely. If he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. His team hopes it39。突然想到那件藍格子襯衫；那些被折成各種各樣形 狀的信紙；那段從街角深巷伊始的友誼；還有那場還沒有開始就宣告了終結的邂逅計劃 …… 那些年那些天的非做不可，終于和青春一樣，都將在我們的人生中謝幕。也曾經(jīng)好像已經(jīng)下定了決心去做某件事，但單片機原理及系統(tǒng)課程設計報告 16 更多的時候是最后又打起了退堂鼓。t really grow up, it seems is not so important。s actions. CSKA said they were surprised and disappointed by Toure39。t charge you more than 35% of your pensation if you win the case. If you are thinking about signing up for a damagesbased agreement, you should make sure you39。查字形碼 MOV DPTR,TABEL MOVC A,A+DPTR MOV P0,A 。中斷初值設定 MOV TL0,0B0H DJNZ R2,RET0 MOV R2,18H MOV A,20H CLR C DEC A MOV 20H,A MOV A,21H CJNE A,00H,PFF 。B 隊加三分 JNB ,BD1 。比賽分數(shù)顯示 。分緩沖區(qū) MOV 33H,01H MOV 34H,00H 。定時計數(shù)器 0 中斷 LJMP TIME。電路的連接不可放過每個細節(jié)，少有疏忽就會出錯。按 下相應按鍵可以達到本系統(tǒng)各個計分功能。 X T A L 218X T A L 119A L E30EA31P S E N29RS T9P 0 .0 /A D 039P 0 .1 /A D 138P 0 .2 /A D 237P 0 .3 /A D 336P 0 .4 /A D 435P 0 .5 /A D 534P 0 .6 /A D 633P 0 .7 /A D 732P 1 . 01P 1 . 12P 1 . 23P 1 . 34P 1 . 45P 1 . 56P 1 . 67P 1 . 78P 3 .0 /R X D10P 3 .1 /T X D11P 3 .2 /I NT 012P 3 .3 /I NT 113P 3 .4 /T 014P 3 .7 / R D17P 3 . 6 / W R16P 3 .5 /T 115P 2 .7 /A 1 528P 2 .0 / A 821P 2 .1 / A 922P 2 .2 /A 1 023P 2 .3 /A 1 124P 2 .4 /A 1 225P 2 .5 /A 1 326P 2 .6 /A 1 427U1A T 8 9 C5 1 圖 1 AT89C51 引腳圖 （ 2） 7 段共陰 LED 顯示器 本設計中采用的是 LED 顯示器 7SEGMPX 系列。即比賽前將時 間設置好，即 12 分鐘，比賽開始時啟動計時，直至計時到零為止。在此設計中共接入了 2 個 7 段共陰 LED 顯示器，用于記錄得分和比賽時間，顯示范圍可以達到 0 到 99 分，基本滿足賽程需求。 關鍵詞： AT89C51； LED 顯示；定時計數(shù)器 單片機原理及系統(tǒng)課程設計報告 1 Abstract This system is designed by single chip microputer AT89C51 as the core ponents. Use 7 with Yin LED as a display device. In the design of the munist party of China access to the two 7 with Yin LED displays, used to record scores and game time, showing the range can reach 0 to 99 points, basic meet schedule requirements. Graded according to the countdown, timing time of 12 minutes every time, when the time to stop and start the time alarm. Timing is the countdown, using the timer/counter interrupt 0, the score with the method of query, the query whether there is a button press, if there are program to jump to the corresponding gauge molecules score accordingly. Keywords: AT89C51,LED display ,timing counter 單片機原理及系統(tǒng)課程設計報告 2 1 引言 設計要求 （ 1）能記錄整個賽程的比賽時間；（ 2）能隨時刷新甲、乙兩隊在整個過程中的比分，輸入錯誤時能夠糾正比分；（ 3）中場交換比賽場地時，能交換甲、乙兩隊比分的位置。 芯片引腳介紹 （ 1） AT89C51 介紹 目前在單片機系統(tǒng)中，應用比較廣泛的微處理器芯片主要為 8XC5X 系列單片機。在單片機系統(tǒng)中使用最多的是如圖 2 所示的七段數(shù)碼顯示器。 計分和時 間顯示電路設計 計分和時間顯示采用四位七段共陰極數(shù)碼管（如圖 2），用單片機的 P0 口用于兩個數(shù)碼管的段選， P2 口低四位用于控制時間顯示的位選 ， P2 口的高四位用以比分顯示的位選，由于采用的是共陰極數(shù)碼管，所以要有電源和上拉電阻。 在這次的實踐與學習當中，盡管區(qū)間困難多多，但我還是從中學到了很多的單片機原理及系統(tǒng)課程設計報告 8 新知識、新技能和解決困難的方法，也最終體驗到了經(jīng)歷困難到最終獲得成功的那種無以言表喜悅。分