ESP32C3 Bare Metal OTA Experiment

About

This is an experiment to do an OTA update on ESP32-C3 in bare-metal.

Most things are hard-coded (i.e. the adresses of the ota partition and the ota slots).

Preparation

First set the ENV variables SSID and PASSWORD to match the settings of your WiFi access point. Your PC needs to be connected to the same access point.

Set the address of your computer in as ENV variable HOST_IP(e.g. "192.168.2.125")

Make sure you have installed devserver

Change THIS_VERSION in main.rs to 2. Compile the application via cargo build --release.

Perform these steps

• esptool --chip esp32c3 elf2image target\riscv32imac-unknown-none-elf\release\esp32c3_ota_experiment
• cp target\riscv32imac-unknown-none-elf\release\esp32c3_ota_experiment.bin firmware.bin

Change THIS_VERSION in main.rs back to 1.

Run

Run devserver --address 192.168.2.125:8080 in a separate terminal (in the project directory). Make sure to replace 192.168.2.125 by the IP of your PC.

To avoid problems run esptool erase_flash first. Now run the application via cargo run --release

The application should connect to your PC, pick up current.txt and see it's own version (1) is below what is available online (2). Now it will download firmware.bin and flash it. After that it will set the OTA partition to use.

In this experiment the reset isn't done automatically. Reset the ESP32-C3 and see the new version boot. The new version will see there is no later version online to flash.

Please Note

Make sure to use the provided bootloader and partition table.

i.e. when flashing manually with espflash use espflash --bootloader bootloader.bin --partition-table partitions.csv