54.4.4. QEOV2_ABZ_OUT

54.4.4.1. Overview

The QEOV2_ABZ_OUT sample project demonstrates the functionality of QEOv2 (Quadrature Encoder Output Version 2) peripheral in generating ABZ quadrature encoder signals based on position information. QEOv2 can receive position information either through software injection or from hardware (such as MMC), and generate standard ABZ quadrature encoder signals based on preset resolution lines, supporting position synchronization for ABZ signal output.

54.4.4.2. Working Process

This example demonstrates two working modes:

  1. Software Position Injection Mode Configuration steps:

    • Initialize QEO module and configure ABZ signal output mode

    • Configure ABZ signal generation parameters:

      • Set encoder resolution (1024 lines/revolution)

      • Set maximum output frequency (250kHz)

      • Enable ABZ signal output

    • Software position injection process:

      • Calculate position increment value

      • Enable software position injection

      • Cyclically inject position values to simulate 2 forward revolutions

      • Wait for ABZ signals to reach injected position

      • Reset position to 0 and disable injection

  2. Hardware Position Input Mode

    In this example, the hardware generator provides position information to QEO, which generates ABZ signals in real-time based on the received position information.

    Configuration steps:

    • Initialize QEO module with the same ABZ parameters as software mode

    • Configure hardware position input:

      • Configure hardware position generator

      • Enable ABZ signal output

    • Enable motor system timestamp function

54.4.4.3. Hardware Setting

Use oscilloscope/logic analyzer to observe the quadrature encoder signals on QEO ABZ output pins (Please refer to Pin Description section).

For MCU that does not support MTG peripheral, a QEI peripheral connected to an ABZ encoder (4000 lines) is required to provide hardware position input for testing.

54.4.4.4. Notes

  1. QEO ABZ Signal Uniformity Issues:

    • When QEO’s position input frequency is greater than 2 times the output ABZ signal frequency (position difference between inputs does not exceed 1/4 line of ABZ), the output maintains uniformity

    • When QEO’s position input frequency is less than 2 times the output ABZ signal frequency (position difference between inputs exceeds 1/4 line of ABZ), uniformity is maintained by dynamically adjusting the minimum width of ABZ signals

54.4.4.5. Running the Example

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

  1. Serial terminal output:

QEO ABZ example
QEO generate ABZ signal with software inject position
QEO generate ABZ signal with hardware provide position
  1. ABZ Signal Output:

Using oscilloscope/logic analyzer, you can observe the ABZ signal waveforms: - A/B signals: Quadrature square waves with 90-degree phase difference - Output occurs every 16 position points, simulating 2 forward revolutions

ABZ Signal Waveform Display