【正文】 共 14 頁 五、總結(jié) 基于 C51 單片機和 PWM 調(diào)光的 LED 燈以 STC10F08XE 作為主控芯片，通過輸出不同的 PWM 占空比實現(xiàn)了對光度的手動調(diào)節(jié)。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。QA9wkxFyeQ^! djsXuyUP2kNXpRWXm Aamp。gTXRm 6X4NGpP$vSTTamp。gTXRm6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。M uWFA5uxY7J nD6YWRr Wwc^vR9amp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^GjqvadNuKNamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTamp。gTXRm 6X4NGpP$vSTTamp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。MuWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^Gjqv^$UE9wEwZQcUE%amp。ksv*3t nGK8! z89Am YWpazadNuGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTamp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。ksv*3t nGK8! z89AmYWv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWv*3t nGK8!z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。MuWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^Gjqv^$U*3t nGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWv*3t nGK8! z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTamp。qYpEh5pDx2zVkum amp。M uWFA5uxY7JnD6YWRr Wwc^vR9CpbK!zn%M z849Gx^Gjqv^$U*3t nGK8! z89AmYWpazadNuKNamp。ksv*3t nGK8!z89Am YWv*3t nGK8!z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。6a*CZ7H$dq8Kqqf HVZFedswSyXTyamp。gTXRm 6X4NGpP$vSTTamp。gTXRm6X4NGpP$vSTTamp。ksv *3t nGK8!z89Am YWpazadNuKNamp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。gTXRm6X4NGpP$vS TTamp。ksv*3t nGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89AmYWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuGK8! z89Am YWpazadNuKNamp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK!zn%Mz849Gx^Gjqv^$UE9wEwZQcUE%amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。gTXRm 6X4NGpP$vSTTamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqv^$UE9wEwZQcUE%amp。qYpEh5pDx2zVkum amp。ksv*3t nGK8! z89Am YWv*3t nGK8! z89Am YWpazadNuKNamp。MuWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^Gjqv^$U*3t nGK8!z89Am YWpazadNuKNamp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。gTXRm6X4NGpP$vSTTamp。ksv*3t nGK8!z89Am YWv*3tnGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8! z89AmYWv*3t nGK8! z89Am YWpazadNuKNamp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^Gjqv^$UE9wEwZQcUE%amp。qYpEh5pDx2zVkum amp。gTXRm 6X4NGpP$vSTTamp。gTXRm6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTamp。qYpEh5pDx2zVkum amp。gTXRm6X4NGpP$vSTTamp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。 } /*********************************************************/ // 延時子程序 /*********************************************************/ void delayms(unsigned char ms) { unsigned char i 。 } } /*********************************************************/ // 定時器 0 中斷服務程序 . /*********************************************************/ void timer0() interrupt 1 { TR1=0 。 TH0=0xfc 。利用公式 ITI ONL t? 可知，利用調(diào)整 PWM 不同的占空比 就可以控制電流的大小?？梢酝ㄟ^調(diào)整 PWM 的周期、 PWM 的占空比而達到控制充電電流的目的。同時，學習使用單片機了解計算機原理與結(jié)構(gòu)的最佳選擇。 現(xiàn)在，這種單片機的使用領(lǐng)域已十分廣泛。 這次設計利用 51 單片機產(chǎn)生占空比可變的矩形波，當產(chǎn)生此矩形波的I/O 通過濾波電路再與 LED 燈相連接后，由于輸出矩形波占空比不斷變化，那么一個周期內(nèi)有一部分時間 LED 導通，一部分時間截止，從整體來看有一個平均電壓，因為 PWM 信號頻率周期很高，我們無法通過肉眼來觀察到每一個周期 LED 燈亮滅的變化過程，所以通過平均電壓的方式來決定 LED燈的亮的程度。 第 8 頁 共 14 頁 電流通斷的變化用 NMOS 管 K2717 實現(xiàn)，三極管 9014 提供驅(qū)動 K2717 的電流 ， PWM 由 輸出，低電平有效。 //1ms 延時常數(shù) 12M TL0=0x18 。 TH0=0xfc 。 while(ms) { for(i = 0 。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。ksv*3t nGK8! z89AmYWpazadNuKNamp。ksv*3t nGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8!z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。qYpEh5pDx 2zVkum amp。qYpEh5pDx2zVkum amp。M uWFA5uxY7JnD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqv^$U*3t nGK8! z89AmYWpazadNuKNamp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK!zn%Mz849Gx^Gjqv^$U*3tnGK8!z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。qYpEh5pDx2zVkum amp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqv^$UE9wEwZQcUE%amp。gTXRm6X4NGpP$vSTTamp。qYpEh5pDx2zVkum amp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z 849Gx^Gjqv^$UE9wEwZQcUE%amp。ksv*3t nGK8! z89Am YWv*3t nGK8! z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。gTXRm6X4NGpP$vSTTamp。gTXRm6X4NGpP$vSTTamp。qYpEh5pDx2zVkum amp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqv^$UE9wEwZQcUE%amp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqv^$U*3t nGK8! z89Am YWpazadNuKNamp。MuWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%Mz849Gx^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%M z849Gx^Gjqv^$UE9wEwZQcUE%amp。ksv*3t nGK8!z89Am YWv*3t nGK8!z89Am YWpazadNuKNamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK!zn%Mz849Gx^Gjqv^$UE9wEwZQcUE%amp。ksv*3t nGK8! z89Am YWpazadNuGK8! z89Am YWpazadNuKNamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。QA9wkxFyeQ^! djsXuyUP2kNXpRWXm Aamp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。gTXRm 6X4NGpP$vSTTamp。M uWFA5uxY7J nD6YWRr Wwc^vR9CpbK! zn%M z849Gx^Gjqvt nGK8! z89AmYWv*3t nGK8! z89AmYWpazadNuKNamp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRr Wwc^vR9amp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。ksv*3t nGK8!z89Am YWv*3t nGK8!z89Am YWpazadNuKNamp。M uWFA5uxY7J nD6YWRrWwc ^vR9CpbK! zn%M z849Gx^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRrWwc^vR9CpbK! zn%M z849Gx^GjqvUE%amp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。M uWFA5uxY7J nD6YWRr Wwc^vR9amp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。ksv*3t nGK8! z89Am YWpazadNuKNamp。qYpEh5pDx2zVkum amp。gTXRm 6X4NGpP$vSTTamp。gTXRm 6X4NGpP$vSTTamp。ksv*3t nGK8!z89Am YWpazadNuKNamp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。M uWFA5ux^Gjqv^$UE9wEwZQcUE%amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。qYpEh5pDx2zVkum amp。ksv*3t nGK8!z89Am YWpazadNuKNamp。ksv