54.4.3. QEO_PWM_OUT

54.4.3.1. Overview

The QEO_PWM_OUT sample project demonstrates the functionality of the QEO (Quadrature Encoder Output) peripheral in controlling PWM output based on position information. QEO can receive position information either through software injection or from hardware (such as MMC), and generate corresponding PWM waveforms based on preset PWM commutation tables and resolution settings. This is commonly used in stepper motor control.

54.4.3.2. Working Process

This example demonstrates two working modes:

  1. Software Position Injection Mode Configuration steps:

    • Initialize QEO module and configure PWM output

    • Configure 4-phase PWM output table:

      • Set PWM forced output state for each phase

      • Configure 4-step commutation sequence for motor phase control

    • Set resolution line count

    • Software position injection process:

      • Calculate position increment per step

      • Enable software position injection

      • Cyclically inject position values to switch PWM output

      • Wait for position calculation completion

      • Disable software position injection

  2. Hardware Position Input Mode

    In this example, the MMC (Motor Motion Control) peripheral provides position information to QEO, which then outputs corresponding PWM waveforms based on the received position information.

    Configuration steps:

    • Initialize QEO module and configure PWM output

    • Configure 4-phase PWM output table:

      • Set PWM channels to non-forced output state (adjustable PWM duty cycle)

    • Configure safety mode output table

    • Configure hardware trigger and safety mode:

      • Set TRGM to trigger QEO entering safety mode

      • Automatically exit safety mode when new position arrives

    • Configure PWM in center-aligned mode

    • Configure MMC position output:

      • Connect MMC position output to QEO through TRGM

      • Configure MMC open-loop prediction mode

    • Enable motor timestamp function

54.4.3.3. Hardware Setting

Observe the output waveform on the specified PWM pins (Please refer to Pin Description section).

54.4.3.4. Running the Example

When the project runs correctly, you will observe the following:

  1. Serial terminal output:

QEO PWM example
QEO generate PWM signal with software inject postion
QEO generate PWM signal with hardware(MMC) provide postion

  1. PWM output waveforms:

Using a logic analyzer, you can observe two different PWM waveforms:

  • Forced output waveform in software position injection mode:

PWM waveform in software position injection mode

  • PWM modulation waveform in hardware position input mode:

PWM waveform in hardware position input mode