本实验使用8253的定时计数器2，GATE2接到开关K1上，CLK2接1MHZ的时钟脉冲，OUT2接示波器观测输出波形，并在数码管上显示“8253---C”。-The timing of the experiments using 8253 counter 2, GATE2 received on the switch K1, CLK2 clock pulses received 1MHZ, OUT2 connected oscilloscope to observe the output waveform and digital display " 8253--- C" .