# Example: General Purpose Timer This example uses the timer group driver to generate timer interrupts at two specified alarm intervals. ## How to Use Example ### Hardware Required * A development board with ESP SoC (e.g., ESP32-DevKitC, ESP-WROVER-KIT, etc.) * A USB cable for Power supply and programming ### 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 [ESP-IDF Getting Started Guide](https://idf.espressif.com/) for all the steps to configure and use the ESP-IDF to build projects. ## Example Output ``` I (0) cpu_start: Starting scheduler on APP CPU. I (325) example: Init timer with auto-reload I (835) example: Timer auto reloaded, count value in ISR: 3 I (1335) example: Timer auto reloaded, count value in ISR: 3 I (1835) example: Timer auto reloaded, count value in ISR: 3 I (2335) example: Timer auto reloaded, count value in ISR: 3 I (2335) example: Init timer without auto-reload I (2835) example: Timer alarmed at 500003 I (3335) example: Timer alarmed at 1000003 I (3835) example: Timer alarmed at 1500003 I (4335) example: Timer alarmed at 2000003 ``` ## Functionality Overview * Configure one timer with auto-reload enabled, alarm period set to 0.5s * On reaching the interval value the timer will generate an alarm * The timer will reload with initial count value on alarm, by hardware * Reconfigure the timer with auto-reload disabled, initial alarm value set to 0.5s * The timer keeps incrementing and in the alarm callback, the software reconfigures its alarm value by increasing 0.5s * The main task will print the count value that captured in the alarm callback ## 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.