1、*【使用說明】:晶振為利用定時器控制產生占空比可變的PW波按K3, PWM值增加，則占空比減小,LED燈漸亮按K4, PWM值減小，則占空比增加,LED燈漸暗當PWM值增加到最大值或減小到最小值時，蜂鳴器將報警丄"丄"丄"丄"丄"丄"尢 丄"KW 丄"丄"丄"KW 丄"丄"丄"%lx 丄"丄"±丄"vz 丄"” " £"* 4 * ,、* I * "、* *| * j *#in

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