Fox Red Labs / Builds / Smart home and radio

Update a board's firmware over the air

New firmware on a board that is already installed somewhere, without plugging it in.

Hardabout 2 min to build

No recorded steps

Some pieces of it have run. There are no recorded steps for this project, so this page does not give any.

What exists:

LP-EM-CC2340R5: Over Bluetooth from a laptop: 43 s for the whole update, with TI's dual-image example. Over Zigbee from Home Assistant: starts, then stalls: 88.7% of a 200 kB image at best (12 transfers, none finished). suspected cause: radio environment.
LP-EM-CC35X1: Over Wi-Fi from a Mac: download about 1 s, install and reboot 8 s, new image running (one attempt)

You would need the board, plus LP-XDS110ET debugger.

Errors and fixes: LP-EM-CC2340R5.

What to build next

Switch a board's LED from Home Assistant over ZigbeeThe board's own LED, switched on and off from Home Assistant

Add a low-power temperature sensor to Home AssistantA low-power Zigbee sensor that sleeps between readings and shows up on your dashboard

Send a sensor reading to a phone over BluetoothA reading your phone or Mac picks up over Bluetooth, no pairing

Every build. The code for all of them is in the GitHub repository.

Evidence and limits43 s over Bluetooth on the CC2340R5; over Wi-Fi on the CC35X1 it installed in 8 s; the Zigbee update has not finished. Ran on 2 boards. Results, sources, timing and limits.

Which boards ran it

Could work LP-EM-CC2340R5: Over Bluetooth from a laptop: 43 s for the whole update, with TI's dual-image example. Over Zigbee from Home Assistant: starts, then stalls: 88.7% of a 200 kB image at best (12 transfers, none finished). suspected cause: radio environment.
Works LP-EM-CC35X1: Over Wi-Fi from a Mac: download about 1 s, install and reboot 8 s, new image running (one attempt)

Experiments (1)

Status	What was tried	Result
Could work	Can Home Assistant update a TI LP-EM-CC2340R5 Zigbee device over the air? CC2340R5, 2026-10-05	Best 88.74% of 200 kB, which is 177.5 kB in 92 minutes at 33 bytes a second, with a Zigbee plug beside the board. It stopped when the board's block requests stopped reaching Home Assistant for 30 s. Twelve transfers,...

Source files

LP-EM-CC2340R5 OAD notes (CC2340R5)

Get the code and tell us how it wentThe clone command, the board folder with its AGENTS.md, reports from others, and the three report forms.

Get the code

Clone the repository and open the board's folder below. AGENTS.md is a plain text file of notes for AI coding assistants, and llms.txt at the root indexes the site for one.

git clone https://github.com/Fox-Red-Labs/fox-red-labs.git

LP-EM-CC2340R5: folder cc2340r5/.
- README: the board's lab notebook (what was run, in order)
- Notes for an AI coding assistant working in this repository: notes for an AI assistant; copy it into your own project if you use one
- FAQ: errors and fixes

Code is BSD-3-Clause, writing is CC BY 4.0; third-party folders keep their own licenses.

Built it? Tell us

Built this, or got stuck? Report it on GitHub with a few short answers. Your report shows here in your words, marked as yours. A failure that repeats on the bench gets its fix here.

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