ESP32-C3

Overview

ESP32-C3 is a single-core Wi-Fi and Bluetooth 5 (LE) microcontroller SoC, based on the open-source RISC-V architecture. It strikes the right balance of power, I/O capabilities and security, thus offering the optimal cost-effective solution for connected devices. The availability of Wi-Fi and Bluetooth 5 (LE) connectivity not only makes the device configuration easy, but it also facilitates a variety of use-cases based on dual connectivity. 1

The features include the following:

  • 32-bit core RISC-V microcontroller with a maximum clock speed of 160 MHz

  • 400 KB of internal RAM

  • 802.11b/g/n/e/i

  • A Bluetooth LE subsystem that supports features of Bluetooth 5 and Bluetooth mesh

  • Various peripherals:

    • 12-bit ADC with up to 18 channels

    • TWAI compatible with CAN bus 2.0

    • Temperature sensor

    • 4x SPI

    • 2x I2S

    • 2x I2C

    • 3x UART

    • LED PWM with up to 16 channels

  • Cryptographic hardware acceleration (RNG, ECC, RSA, SHA-2, AES)

System requirements

Prerequisites

Espressif HAL requires binary blobs in order work. The west extension below performs the required syncronization to clone, checkout and pull the submodules:

west espressif update

Note

It is recommended running the command above after west update.

Building & Flashing

Build and flash applications as usual (see Building an Application and Run an Application for more details).

# From the root of the zephyr repository
west build -b esp32c3_devkitm samples/hello_world

The usual flash target will work with the esp32c3_devkitm board configuration. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b esp32c3_devkitm samples/hello_world
west flash

Open the serial monitor using the following command:

west espressif monitor

After the board has automatically reset and booted, you should see the following message in the monitor:

***** Booting Zephyr OS vx.x.x-xxx-gxxxxxxxxxxxx *****
Hello World! esp32c3_devkitm

Debugging

As with much custom hardware, the ESP32C3 modules require patches to OpenOCD that are not upstreamed. Espressif maintains their own fork of the project. The custom OpenOCD can be obtained by running the following extension:

west espressif install

Note

By default, the OpenOCD will be downloaded and installed under $HOME/.espressif/tools/zephyr directory (%USERPROFILE%/.espressif/tools/zephyr on Windows).

The Zephyr SDK uses a bundled version of OpenOCD by default. You can overwrite that behavior by adding the -DOPENOCD=<path/to/bin/openocd> -DOPENOCD_DEFAULT_PATH=<path/to/openocd/share/openocd/scripts> parameter when building.

Here is an example for building the Hello World application.

# From the root of the zephyr repository
west build -b esp32c3_devkitm samples/hello_world -- -DOPENOCD=<path/to/bin/openocd> -DOPENOCD_DEFAULT_PATH=<path/to/openocd/share/openocd/scripts>
west flash

You can debug an application in the usual way. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b esp32c3_devkitm samples/hello_world
west debug

References

1

https://www.espressif.com/en/products/socs/esp32-c3