lpc932单片机PWM输出-lpc932 SCM PWM output 下载
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LPC932用CCU实现PWM-LPC932 CCU with PWM 下载
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可以用LPC932产生脉宽可调的PWM，然后通过外围电路实现DA转换-LPC932 can produce the PWM pulse width adjustable, and then through the external circuit DA Converters 下载
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he LPC932 can be used to create a Pulse Width Modulated PWM signal. That s an analog signal, with only 2 discrete levels, for example 0V and 5V and a constant period. The current value of this signal at a certain poiTnt of time is proportional to its Duty Cycle. That s the High Time during one period divided by the period. It can also be calculated as the average value during a particular period. That means after low pass filtering, (e.g. RC circuit) the signal becomes analog, with an actual value controlled by the microcontroller. The PWM functionality enables the LPC932 to control for example the speed of DC motors or the brightness of electric lighting. -he LPC932 can be used to create a Pulse Width Modulated PWM signal. That s an analog signal, with only two discrete levels, for example 0V and 5V and a constant period. The current value of this signal at a certain time is of poiTnt proportional to its Duty Cycle. That s the High Time during one period divided by the period. It can also be calculated as the average value during a particular period. That means after low pass filtering (eg RC circuit) the signal becomes analog, with an actual value controlled by the microcontroller. The PWM functionality enables the LPC932 for example to control the speed of DC motors or the brightness of electric lighting. 下载
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Uses the general purpose timer T1 of the LPC932 for generating PWM signals-Uses the general purpose timer T1 of the LPC 932 for generating PWM signals 下载
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The general purpose timer T1 of the LPC932 is set up to PWM Mode 6. In this mode it becomes a 8 bit up-counter with a special 8 bit reload on overflow. The reload values are alternating and represent the High Time and one period minus the High Time (=Low Time) of the PWM signal. On each overflow there can be an interrupt or a toggle of a certain port pin. The assigned port pin of T1 is P0.7.- 下载
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