Download Guidelines

[中文]

You can download firmware to ESP32-S31 via UART and USB.

To download via UART:

1. Before the download, make sure to set the chip or module to Joint Download Boot mode, according to Table Chip Boot Mode Control.

2. Power up the chip or module and check the log via the UART0 serial port. If the log shows “waiting for download”, the chip or module has entered Joint Download Boot mode.

3. Use the Flash Download Tool to flash firmware into flash via UART.

4. After the firmware has been downloaded, configure the chip to work in SPI Boot mode according to Table Chip Boot Mode Control.

5. Power up the chip or module again. The chip will read and execute the new firmware during initialization.

To download via USB:

1. If the flash is empty, set the chip or module to Joint Download Boot mode, according to Table Chip Boot Mode Control.

2. Power up the chip or module and check the log via USB serial port. If the log shows “waiting for download”, the chip or module has entered Joint Download Boot mode.

3. Use the Flash Download Tool to flash firmware into flash via USB.

4. After the firmware has been downloaded, configure the chip to work in SPI Boot mode according to Table Chip Boot Mode Control.

5. Power up the chip or module again. The chip will read and execute the new firmware during initialization.

6. If the flash is not empty, start directly from Step 3.

Note

• For firmware download instructions, see also ESP Product Firmware Download Instructions.

• For how to check serial port output, see also Establish Serial Connection with ESP32-S31.

• It is advised to download the firmware only after the “waiting for download” log shows via the serial port.

• Serial tools cannot be used simultaneously with the Flash Download Tool on one COM port.

• The USB auto-download will be disabled if the following conditions occur in the application, where it will be necessary to set the chip or module to Joint Download Boot mode first by configuring the strapping pin.

  • USB PHY is disabled by the application;

  • USB is configured for other USB functions, e.g., USB host, USB standard device;

  • USB IOs are configured to other peripherals, such as UART and LEDC.

• It is recommended that the user retains control of the strapping pins to avoid the USB download function not being available in case of the above scenario.

• It is recommended to retain the UART download interface, as the current RF test firmware only supports the UART interface.