应用单片机对直流电机的加减速控制（汇编），利用蜂鸣器的频率产生音乐，单片机的定时器和中断进行24秒篮球倒计时的数码管显示。-SCM application acceleration and deceleration of the DC motor control (assembly), the frequency of use of the buzzer produces music, single-chip timers and interrupt the countdown for 24 s