Peripheral Examples
The ESP series chips integrate a rich set of peripheral interfaces, which can efficiently implement communication with external devices such as sensors, displays, storage devices, etc., thereby completing core functions such as data collection, signal control, information transmission, and image transmission. However, due to differences in chip hardware design, the peripheral characteristics of different chip models may vary, such as the number of peripherals, the multiplexing capability of GPIO pins, and the support for remapping, etc.
To help master the use of peripherals, this document will first explain the core purposes of each peripheral, the requirements for pin configuration, and the support for pin multiplexing/remapping; then, based on the commonly used peripheral development examples of the official ESP-IDF, it will explain the actual calling methods of modules such as gpio, ledc, i2c, uart, spi (including master / slave mode), adc, etc. More examples can be referred to peripherals example folder.
In ESP32, the general essential steps for each peripheral mainly include basic parameter configuration (such as mode, pin, frequency, etc.) and peripheral startup/enabling. After completing these two steps, most peripherals can operate normally. However, for a few peripherals, such as UART, if DMA or interrupt mode is used in the application, additional buffer configuration is required to work normally. In addition, some peripherals, such as I2C, need to explicitly release related resources after the task is completed to ensure system stability.