49.1. HRPwm Output

49.1.1. Overview

The pwm project demonstrates how to configure and output various PWM waveforms using the MCU’s HRPWM module, including:

  • Forced output mode: Control the PWM pin output high or low level by software

  • Fault mode: Demonstrate PWM output protection and automatic recovery triggered by external fault signals

  • Edge-aligned PWM: Output edge-aligned PWM waveform with variable duty cycle

  • Center-aligned PWM: Output center-aligned PWM waveform with variable duty cycle

  • Frequency-variable PWM: Demonstrate dynamic adjustment of PWM output frequency

49.1.2. Configurations

49.1.3. Running the Demo

  • After power on, the serial port will sequentially output prompt information for each function mode

  • The oscilloscope can observe P0 and P2 pins outputting high level, low level, edge-aligned PWM, center-aligned PWM, and frequency-variable PWM waveforms in turn

  • In edge-aligned and center-aligned modes, P0 is the target waveform with gradually changing duty cycle, and P2 is the reference waveform

  • In fault mode, when an external fault signal is triggered, the PWM output enters protection state and automatically recovers on hardware or software events

  • In frequency-variable mode, the PWM output frequency changes gradually

  • Serial port printing information:

hr pwm example

>> Test force HRPWM output on P0 and P2
Output high
Output low

>> Generate edge aligned waveform
Two waveforms will be generated, HRPWM P0 is the target waveform
whose duty cycle will be updated from 0 - 100; HRPWM P2 is a reference

>> Generate central aligned waveform
Two waveforms will be generated, HRPWM P0 is the target waveform
whose duty cycle will be updated from 0 - 100; HRPWM P2 is a reference

>> Generate frequency-variable waveforms
whose frequency will be updated; HRPWM P0 is the target waveform
test done

Note

The PWM waveform is output only once. If you need to observe the waveform again, please rerun the program.