ESP32

ESP32

Basically the ESP32 can serve as an alternative to owpost.

The ESP32 family of chips has on-board wifi and GPIO pinds that can serve as a 1-wire bus master.

The device is not as powerful as a Raspbaerry Pi

• Minimal operating system (no Linux)
• Does not support owserver (or the owfs ecosystem)
• Uses a subset of python (micropython) which fortunately covers our uses
• Lower power, lower cost

Hardware

The

Micropython

There are a number of tutorials on installing micropython on the ESP32. The official documentation is excellent and has the firmware download links.

install esptool

Due to a problem in the distribution version of esptool (`sudo apt install esptool) on Ubuntu 24.04 I needed to perform:

sudo apt install python3-pip
pip install --break-system-packages esptool

The actual program will be in ~/.local/bin whih needs to be in your PATH (e.g. export PATH="$PATH:~/.local/bin"

install firmware

• esptool erase_flash
• esptool write_flash 0x1000 ESP....

Software

Use mpremote to talk to ESP device

Install mpremote

pip install mpremote

Modules

Built in

• machine
• os
• time
• onewire, ds18x20
• network
• urequests

External modules

• tomli
  • micropython version
  • Using suggested shortcut with no datetime needed of _parser.py -> tomli.py
• jwt and hmac
  • From Miguel Grinberg