基于51单片机的 ，运用查表法产生正弦波的程序，频率和占空比均可调-Based on 51 single-chip, procedures, frequency and duty cycle can be adjusted for use of look-up table method generates a sine wave

方波信号发生器设计（幅度、频率、占空比可调）-Square-wave signal generator design (amplitude, frequency, duty cycle adjustable)

飞思卡尔的PWM代码，通过改变PWM输出的占空比，可以做出特定频率的方波-Freescale s PWM code by changing the duty cycle of the PWM output, you can make a specific frequency square wave