.. _pwmv2_output:

PWM输出
==========

概述
------

**pwm** 工程主要演示了如何配置几种不同类型的pwm波形并通过MCU的引脚进行输出。

- 强制输出

- 边沿对齐pwm

- 中心对齐pwm

- 中心对齐互补pwm

- PWM故障模式

配置
------

- 一个双通道示波器

- 安装串口终端，查看 :ref:`板子信息 <board_resource>` 并配置串口终端参数

-  :ref:`PWM_P0和PWM_P1引脚 <board_resource>` 根据板子型号查看具体信息

运行现象
------------

- 上电后，通过示波器可依次观测到P0、P1输出高电平、低电平、边沿对齐PWM、中心对齐PWM、中心对齐互补PWM

- 失效引脚给定高电平后，P0和P1引脚PWM输出低电平，失效引脚给定低电平后，P0和P1引脚P恢复正常

- 串口打印如下信息:


.. code-block:: console

   pwm example


   >> Test force PWM output on P0 and P1
   Output high
   Output low

   >> Generate edge aligned waveform
   Two waveforms will be generated, PWM P0 is the target waveform
   whose duty cycle will be updated from 0 - 100 and back to 0; PWM P1 is a reference

   >> Generate central aligned waveform
   Two waveforms will be generated, PWM P0 is the target waveform
   whose duty cycle will be updated from 0 - 100 and back to 0; PWM P1 is a reference

   >> Generate central aligned waveform in pair
   Two waveforms will be generated in pair, PWM P0 and P1 are target
   waveforms whose duty cycle will be updated from 0 - 100 and back to 0
   test done


.. note::

   只依次输出一次PWM波形，如果需要再次观测波形，需要重新运行程序。