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04df1f3a42
Enables building C3 examples in CI. Fixes related warnings/errors and disables examples that cannot run.
79 lines
3.2 KiB
Markdown
79 lines
3.2 KiB
Markdown
| Supported Targets | ESP32 | ESP32-S2 |
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# Rotary Encoder Example
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(See the README.md file in the upper level 'examples' directory for more information about examples.)
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The PCNT peripheral is designed to count the number of rising and/or falling edges of an input signal. Each PCNT unit has two channels, which makes it possible to extract more information from two input signals than only one signal.
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This example shows how to make use of the HW features to decode the differential signals generated from a common rotary encoder -- [EC11](https://tech.alpsalpine.com/prod/e/html/encoder/incremental/ec11/ec11_list.html).
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The signals a rotary encoder produces (and what can be handled by this example) are based on a 2-bit gray code available on 2 digital data signal lines. The typical encoders use 3 output pins: 2 for the signals and one for the common signal usually GND.
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Typical signals:
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```
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A +-----+ +-----+ +-----+
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+-----+ +-----+
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B +-----+ +-----+ +-----+
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+-----+ +-----+
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+--------------------------------------->
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CW direction
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```
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## How to Use Example
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### Hardware Required
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* An ESP development board
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* EC11 rotary encoder (or other encoders which can produce quadrature waveforms)
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Connection :
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```
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+--------+ +---------------------------------+
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| A +--------------+ GPIO_A (internal pull up) |
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+-------+ | | |
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| | | GND +--------------+ GND |
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+-------+ | | |
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| B +--------------+ GPIO_B (internal pull up) |
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+--------+ +---------------------------------+
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```
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### Build and Flash
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Run `idf.py -p PORT flash monitor` to build, flash and monitor the project.
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(To exit the serial monitor, type ``Ctrl-]``.)
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See the [Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/get-started/index.html) for full steps to configure and use ESP-IDF to build projects.
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## Example Output
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```
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I (181323) example: Encoder value: 0
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I (182323) example: Encoder value: 0
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I (183323) example: Encoder value: -12
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I (184323) example: Encoder value: -18
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I (185323) example: Encoder value: -24
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I (188323) example: Encoder value: 4
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I (189323) example: Encoder value: 8
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I (190323) example: Encoder value: 8
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I (191323) example: Encoder value: 8
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```
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This example enables the 4X mode to parse the rotary signals, which means, each complete rotary step will result PCNT counter to increase/decrease by 4, depending on the direction of rotation.
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## Troubleshooting
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For any technical queries, please open an [issue] (https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.
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