mirror of
https://github.com/espressif/esp-idf.git
synced 2024-10-05 20:47:46 -04:00
75 lines
2.4 KiB
Markdown
75 lines
2.4 KiB
Markdown
|
| Supported Targets | ESP32 | ESP32-S3 |
|
||
|
|
| ----------------- | ----- | -------- |
|
||
|
|
|
||
|
|
# MCPWM sync Example
|
||
|
|
|
||
|
|
(See the README.md file in the upper level 'examples' directory for more information about examples.)
|
||
|
|
|
||
|
|
This example aims to show howto sync those timers within the same MCPWM unit to produce fully synchronized output.
|
||
|
|
|
||
|
|
The example will:
|
||
|
|
|
||
|
|
- init MCPWM
|
||
|
|
- sync all three timers with the help of one extra GPIO
|
||
|
|
- mess the synchronized timers by stopping and restarting
|
||
|
|
- sync all three timers with software sync event, no GPIO required. (Only targets with `SOC_MCPWM_SWSYNC_CAN_PROPAGATE` ability can support).
|
||
|
|
- sync all three timers, but adding 10% delay between pulses from different channels
|
||
|
|
|
||
|
|
## How to Use Example
|
||
|
|
|
||
|
|
### Hardware Required
|
||
|
|
|
||
|
|
* An ESP32/ESP32S3 development board
|
||
|
|
|
||
|
|
It is recommended to have an oscilloscope or logic analyzer to verify the output pulse
|
||
|
|
|
||
|
|
Connection :
|
||
|
|
|
||
|
|
| Pin | Func | Mode |
|
||
|
|
| :---------: | :----------------: | :----: |
|
||
|
|
| GPIO_NUM_16 | MCPWM0.Timer0.GenA | Output |
|
||
|
|
| GPIO_NUM_17 | MCPWM0.Timer1.GenA | Output |
|
||
|
|
| GPIO_NUM_18 | MCPWM0.Timer2.GenA | Output |
|
||
|
|
| GPIO_NUM_21 | GPIO_SYNC0 | INPUT |
|
||
|
|
| GPIO_NUM_19 | simulate input | OUTPUT |
|
||
|
|
|
||
|
|
GPIO_NUM_21 and GPIO_NUM_19 **SHOULD** be wired together to provide simulated input.
|
||
|
|
|
||
|
|
Above pin selection can be changed within file `mcpwm_sync_example.c`.
|
||
|
|
|
||
|
|
### Build and Flash
|
||
|
|
|
||
|
|
Run `idf.py -p PORT flash monitor` to build, flash and monitor the project.
|
||
|
|
|
||
|
|
(To exit the serial monitor, type ``Ctrl-]``.)
|
||
|
|
|
||
|
|
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.
|
||
|
|
|
||
|
|
## Example Output
|
||
|
|
|
||
|
|
```
|
||
|
|
I (306) sync_example: MCPWM sync example
|
||
|
|
I (306) sync_example: PWM started, not synchronized
|
||
|
|
I (3316) sync_example: Sync timers with GPIO approach
|
||
|
|
I (3326) sync_example: Output should already be synchronized
|
||
|
|
I (6326) sync_example: force synchronous lost
|
||
|
|
I (9326) sync_example: Output should already be synchronized on esp32s3
|
||
|
|
I (12336) sync_example: Each output pulse should be placed with 10 percents of period
|
||
|
|
```
|
||
|
|
|
||
|
|
Overall pulse graph:
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
Sync:
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
Sync with phase:
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
## Troubleshooting
|
||
|
|
|
||
|
|
For any technical queries, please open an [issue] (https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.
|