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75 lines
2.4 KiB
Markdown
75 lines
2.4 KiB
Markdown
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| Supported Targets | ESP32 | ESP32-S3 |
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| ----------------- | ----- | -------- |
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# MCPWM sync 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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This example aims to show howto sync those timers within the same MCPWM unit to produce fully synchronized output.
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The example will:
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- init MCPWM
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- sync all three timers with the help of one extra GPIO
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- mess the synchronized timers by stopping and restarting
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- sync all three timers with software sync event, no GPIO required. (Only targets with `SOC_MCPWM_SWSYNC_CAN_PROPAGATE` ability can support).
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- sync all three timers, but adding 10% delay between pulses from different channels
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## How to Use Example
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### Hardware Required
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* An ESP32/ESP32S3 development board
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It is recommended to have an oscilloscope or logic analyzer to verify the output pulse
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Connection :
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| Pin | Func | Mode |
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| :---------: | :----------------: | :----: |
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| GPIO_NUM_16 | MCPWM0.Timer0.GenA | Output |
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| GPIO_NUM_17 | MCPWM0.Timer1.GenA | Output |
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| GPIO_NUM_18 | MCPWM0.Timer2.GenA | Output |
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| GPIO_NUM_21 | GPIO_SYNC0 | INPUT |
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| GPIO_NUM_19 | simulate input | OUTPUT |
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GPIO_NUM_21 and GPIO_NUM_19 **SHOULD** be wired together to provide simulated input.
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Above pin selection can be changed within file `mcpwm_sync_example.c`.
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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 (306) sync_example: MCPWM sync example
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I (306) sync_example: PWM started, not synchronized
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I (3316) sync_example: Sync timers with GPIO approach
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I (3326) sync_example: Output should already be synchronized
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I (6326) sync_example: force synchronous lost
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I (9326) sync_example: Output should already be synchronized on esp32s3
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I (12336) sync_example: Each output pulse should be placed with 10 percents of period
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```
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Overall pulse graph:
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Sync:
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Sync with phase:
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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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