SmartHomeShop Docs

Version 2.0 Upgrade Guide

Required one-time USB-C update: UltimateSensor V1 firmware 2.0 was released on July 27, 2026. Devices running firmware 1.13 or older must install this update once through USB-C. Do not install this framework migration through Home Assistant or OTA.

After version 2.0 has been installed through USB-C, future 2.x firmware updates will work wirelessly again.

What Changes

Version 2.0 moves every UltimateSensor V1 firmware variant from Arduino to ESP-IDF while retaining the existing hardware and Home Assistant entities:

  • native LD2450 tracking for up to three people;
  • four polygon zones and two exclusion zones;
  • two virtual entry lines and people counting;
  • the existing Back Light entity with the same LED colour order;
  • WiFi and Ethernet/PoE firmware variants;
  • Basic and Complete hardware variants;
  • local Home Assistant and SmartHomeShop App cloud firmware.

A USB-C installation returns the device to its factory settings, so your zones are not kept. Rectangular zones from firmware older than 1.11 are not converted either. Save your current LD2450 polygon zones, exclusion zones and entry lines before updating.

Before You Start

Hardware step required: The UltimateSensor V1 enclosure must be opened and the blue LD2450 module must be removed before USB-C flashing. On V1, the LD2450 can prevent the device from entering flash mode.

  • Save your current LD2450 zone configuration.
  • Note your WiFi details when using a WiFi variant.
  • Use a USB-C cable that supports data, not a charging-only cable.
  • Use Chrome or Edge on a desktop or laptop.
  • Disconnect Ethernet/PoE and all other power before opening the enclosure.
  • Note the orientation of the blue LD2450 module before removing it.
  • Check whether your model is Basic or Complete. Complete includes particulate matter measurement.
  • Check whether you use WiFi or Ethernet/PoE and local Home Assistant or SmartHomeShop App cloud firmware.

Install Version 2.0

Firmware installer: open the UltimateSensor V1 installer in Chrome or Edge.

  1. Disconnect USB-C, Ethernet/PoE and all other power from the UltimateSensor V1.
  2. Open the enclosure carefully. Use the small cutout at the bottom for a flat screwdriver.
  3. Note the orientation of the blue LD2450 module and gently pull it straight out of its connector.
  4. Connect the UltimateSensor V1 directly to your computer with a USB-C data cable.
  5. Open the SmartHomeShop firmware installer in Chrome or Edge.
  6. Select UltimateSensor with hardware version V1, not V2 or UltimateSensor Mini. The link above already selects this.
  7. Select the correct WiFi or Ethernet/PoE, Basic or Complete, and local or cloud firmware variant.
  8. Start the installation and wait until the website confirms that flashing is complete.
  9. Disconnect the USB-C cable before touching or reinstalling the LD2450 module.
  10. Reinstall the LD2450 module in exactly the same orientation and press it straight into the connector.
  11. Close the enclosure and reconnect the normal power source.
  12. Reconnect WiFi through the ultimatesensor hotspot (see the Installation Guide), then Home Assistant or the SmartHomeShop App when required.
  13. Redraw your zones, exclusion zones and entry lines in the Room Designer of the SmartHomeShop integration.

Warning: Installing the module in the wrong orientation can damage the hardware. Never remove or reinstall the LD2450 while the UltimateSensor is powered.

After the Upgrade

Confirm in Home Assistant that Software Version reports 2.0 or newer. Also verify:

  • CO2, temperature, humidity, illuminance, VOC and NOx;
  • PIR motion and LD2450 occupancy and target tracking;
  • OLED display and Back Light;
  • particulate matter values on a Complete model;
  • WiFi or Ethernet connectivity for the installed variant.

Future 2.x releases can be installed through the normal firmware update entity in Home Assistant. Another USB-C installation is not required unless a future release explicitly says so.

Check your Home Assistant automations and dashboards too. Firmware 1.10 and older used other names for zones and targets:

Old entity Entity now
Zone 1 Occupancy Polygon Zone 1 Presence
Moving Target, Still Target Tracking Moving Target, Tracking Still Target
Target 1 Active No direct replacement, use Radar Target Count
Occupancy Off Delay Tracking Presence Timeout

Need Help?

If you have questions about opening the enclosure, removing the LD2450 or installing firmware 2.0, join the SmartHomeShop Discord community.