用C实现信号发生装置：1、正弦波：频率、幅度可调。

2、三角波：频率、幅度可调。

3、方 波：频率、幅度、占空比可调。

4、按键：波形切换、频率调节、幅度调节、方波占空比调节。

5、显示：信号的频率、幅度，在方波时还要显示占空比。

-Implementation using C Signal: 1, sine wave: frequency, amplitude adjustable. 2, triangle-wave: frequency, amplitude adjustable. 3, square wave: the frequency, amplitude, duty cycle adjustable. 4, button: switch waveform, frequency regulation, rate regulation, adjust the duty cycle square wave. 5, show that: the signal frequency, amplitude, when they showed at the duty cycle square wave.