Reprogramming ZTLC9/ZHU2318 Module in Smart Switch: Step-by-Step Guide

Found a ZTLC9 module in a switch. Anyone reprogrammed this module?


/ Frank

Hey, this is a Zigbee module. Why would you want to reprogram that? It can already work without a cloud when you use, for example, zigbee2mqtt with Home Assistant.

By the way, it looks like a Zigbee version of WBLC9:


The following images are from the WBLC9 docs and the similiarity is very high. Still, it's a Zigbee module, not WiFi, so it should work with zigbee2mqtt out of the box.

And I have another question about the ZTLC9 module. Is it possible to somehow change the antenna to one with higher gain? WBLC9 has information in the description about the presence of a ceramic antenna on the board. But which one is it? Can it be replaced, for example, with a WiFi antenna from a laptop?

Custom firmware for this device (and many more) is available here: https://github.com/romasku/tuya-zigbee-switch
The thread for this device: https://github.com/romasku/tuya-zigbee-switch/pull/223

Tuya firmware is not the best and never receives updates. It can be unreliable, missing features, spamming the network.
Basic functions work, but there are plenty of reasons to replace it.

Whoa, that's a very good job, @andrei_lazarov ! Please consider posting your full information in our teardowns topic, as a separate guide. Then we could also feature it on our devices list:
https://openbekeniot.github.io/webapp/devicesList.html

Hi! I was just sharing the Zigbee custom firmware project (it's not my work, but I have some contributions).
This topic came up on Google when I searched for 'ZTLC9'.

OpenBeken looks very cool! But I see it's focused on Wi-Fi modules. It doesn't have much in common with the Zigbee project.
So I don't see why we should add this device to the OpenBeken list.

Romasku's project has a list of supported devices (Tuya Zigbee switches based on Telink chips, and recently Silabs):
https://github.com/romasku/tuya-zigbee-switch/blob/main/docs/supported_devices.md