How to detect a PIR sensor

Complete newbie on home automation, but fine with most things IT, I’ve set up latest version of openHAB on a recent Pi4, and connected a CC2531 controller to a USB port. System appears to detect the controller and reports it online. Looking at Thing Properties on the Information panel, I see zigbee_logicaltype is “UNKNOWN”. I know that may be my problem, but it isn’t the only one.

Assuming the controller may be working, I want to connect a PIR sensor. I have a Sonoff SNZB-03, I’ve taken out the separator to switch it on and poked the reset switch to make it try to pair, but see no evidence that it’s been detected. Is there something I need to do with the controller to tell it to detect new devices?

I’m assuming the CC2531 is both the network controller and a device-handler; is that right? And that if I want to expand my system beyond whatever the controller can handle, I can add more CC2531s configured as just routers, yes?

Thanks for any advice you can offer

You need to put the coordinator into pairing mode. This happens when you go to Things → Inbox → + → Zigbee → Scan for devices

Once it’s scanning for devices, press the button to pair and the device should join the network.

However, if you’ve other problems with the coordinator then that might not work. Looking at my coordinator Thing, the zigbee_logicaltype should be COORDINATOR. If it’s not set to that, it seems likely that the pairing isn’t going to work anyway.

The docs do say that you need to flash an alternative firmware onto the CC2531.

Needs extra hardware and correct firmware (might be hard to find) for flashing.
There are also cheap copies of the CC2531 Stick available on eBay, Aliexpress, etc. like this (opens new window)and a module to flash the firmware like this (opens new window)including a connector board(opens new window)
Also CC2530, CC2538 or CC2650 may work with the correct firmware but are not suggested

If you’ve not done that I’m not surprised it’s not working. You didn’t say.

I am by far no expert on Zigbee, but my understanding is that any mains powered device is also a router. So you only need the one coordinator as long as you remain under the Zigbee network max size (>65000 devices).

Thanks very much for that advice Rich. I don’t see the Scan for devices in Inbox, presumably because the controller firmware isn’t right. When I ordered it, I told the supplier to flash the controller firmware, but I was looking at Home Assistant at the time, so I guess that makes a difference.


Just to be clear, navigate to Things, click the +, select Zigbee from the list. Only then will you see the Scan button.

If you don’t see the scan button then it’s probably because your coordinator is not working with the binding.