54.4.3. QEOV2_WAVE_OUT

54.4.3.1. Overview

The QEO_WAVE_OUT sample project demonstrates the functionality of QEOv2 (Quadrature Encoder Output Version 2) peripheral in generating three-phase waveforms based on position information. QEOv2 can receive position information through software injection, and generate three phase-adjustable cosine waves based on preset resolution lines, which can be used to modulate PWM duty cycles.

54.4.3.2. Working Process

This example demonstrates waveform generation in software position injection mode:

Configuration steps:

  • Initialize QEO module and configure wave output mode:

    • Set wave type as cosine

    • Set resolution lines (4 lines)

    • Configure phase shifts for three-phase output (120°/240°)

  • Software position injection process:

    • Calculate position increment value

    • Enable software position injection

    • Cyclically inject position values for wave generation

    • Sample and record wave output values

    • Disable position injection

54.4.3.3. Features

  1. Wave Generation Features:

    • Supports three independent cosine wave outputs

    • Configurable phase shift for each output

    • Selectable wave type (cosine)

    • Supports wave amplitude range limitation

    • Supports VD/VQ input (can be from CLC)

    • Supports PWM duty cycle modulation

54.4.3.4. Running the Example

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

  1. Serial terminal output:

QEO DAC wave example
QEO generate wave with sofeware inject postion
qeo wave0 output:
4294967231
4294320511
4292380543
4289148543
4284626559
4278817215
4271723967
4263351231
4253703935
4242787967
4230609855
4217176959
4202497343
4186579839
4169434111
4151070399
...
qeo wave1 output:
1073742315
1028424448
983780736
939838187
896622827
854161110
812478230
771599680
731549760
692352875
654032427
616611283
580112595
544558249
509969001
476366270
443770281
412200745
381676478
352215358
323836286
296555113
...
qeo wave2 output:
1073742315
1119706795
1166290390
1213465131
1261202603
1309473664
1358249600
1407501035
1457197867
1507310891
1557809281
1608663254
1659841537
1711313494
1763048278
1815014315
1867180993
1919516545
1971989142
2024567723
2077220118
2129915137
2182619773
2235304168
2287935613
2340482429
2392912936
2445195581
...

  1. Wave Output:

Using tools like Excel to process the serial output data, you can obtain the three-phase cosine waveform: - Three outputs are cosine waves with 120° phase differences - Wave period is determined by resolution lines - Wave amplitude range is 0-0xFFFFFFFF (when not limited)

Three-phase Cosine Waveform