Home Assistant SkyConnect - official radio USB dongle will be compatible with both Zigbee and OpenThread (including Matter/CHIP over Thread)

From my experience, “USB stick” or “USB key” also commonly refers to USB flash drives, while “USB dongle” is usually used when talking about USB wireless radio dongles for example Bluetooth and Wi-Fi that connects to a computer to extend functionality, and “USB adapter” is normally used when referring to adapters that convert ports to handle different types of connectors (such as DVI to HDMI or USB to serial port adapters).

That is basically what Wikipedia has to say in its article on “Dongle” today:


Any idea how the SkyConnect will stack up against the ConBee 2 which has a strong signal range via power-amplifier (and if Conbee 2 will be updated to handle Matter)?

I don’t think the Conbee 2 has the necessary hardware to be upgraded to support Thread (it’s not matter, because matter sits on TOP of the networking protocol.)

ConBee II and RaspBee II are based on the older ATSAMR21B18 by Microchip Technology so at least on paper the newer EFR32MG21 SoC (radio MCU chip) hardware from Silicon Labs kicks their a** in every datasheet specification category, see:


Compare CPU, RAM/Memory, Flash/Storage, radio (Receive Sensitivity, Output Power in dBm, RX and TX mA, etc.), etc. specifications, etc. and so on between EFR32MG21 and ATSAMR21B18 SoC radios.

It should however be noted that Silabs has since then also released the even newer EFR32MG24 and while it not make a better dedicated single protocol radio it probably make a better multi-protocol radio.

Other than migrating from Conbee/Raspbee that is really an off-topic discussion in this specific thread, but FYI, ATSAMR21B18 does not support a Thread protocol stack like OpenThread so Conbee II (and RaspBee II) will therefore for sure never be officially updated to support the Thread wireless protocol, however, earlier this year I did read that comment somewhere from Phoscon/Dresden-Elektronik lead developer that their company are working on the development of ConBee III / ConBee 3 Zigbee Coordinator, (though there was no mention if that will also support Thread/OpenThread as well or not, though I would be a little bit surprised if they at least not choose to go with a radio SoC hardware that has multi-protocol support to try to make the hardware of their new product a little more future-proof just in case).

Anyway, long follow-up answer there is; if Phoscon/Dresden-Elektronik, or someone else, makes a competing Thread USB adapter then it should or at least could in theory be compatible with Home Assistant’s upcoming Thread/Matter integration as long as it comes with OpenThread firmware with Spinel + HDLC-Lite over UART protocol support, see discussion here → https://github.com/home-assistant/addons-development/issues/38


Apricate your informative answer. Then Ill await the HA SkyConnect, may it come ASAP!

FYI, while this official Home Assistant SkyConnect USB Stick will probably be an excellent option for early adopters that just want to buy a few of the upcoming devices using the new upcoming Matter (Project CHIP) standard over the Thread protocol as well as those casual users (non-power users) that are sure that they will never connect loads of Zigbee devices (100+) to this single radio adapter, potential buyers should still probably be made aware in advance before buying that this official Home Assistant SkyConnect USB Stick on paper in a multi-protocol setup configured to concurrently use both Zigbee and Thread protocols over the same radio with a large Zigbee network (100+ devices) as well as several Thread/Matter devices will probably not get as good as performance as simply using a dedicated Zigbee USB adapter with a large Zigbee network and then just using this official Home Assistant SkyConnect USB Stick as a dedicated adapter for Thread/Matter only.

That is, when using multiple wireless protocols at the same time on a single radio chip as a multi-protocol adapter this risk becoming a “Jack of all trades, master of none” product, as on paper today, no existing single multiprotocol radio SoC using Matter/CHIP over Thread in combination with Zigbee at the same time should be able to perform as optimal as simply using separate dedicated radio adapters for each wireless protocol. This is totally understandable considering that it will need to handle the work of two radios, even with the protocol stack being off-loaded from the adapter’s MCU to the Host System CPU. The point remains that by using dedicated coordinator/controller radio adapters for each protocol today you are more likely to get the best performance for each protocol if that is what you are looking for. (This fact may of course change in the future over time with newer radio technologies + improved radio time management frameworks and protocol stacks from radio chip manufacturers).

Thus if you plan on potentially using it with a lot of Zigbee devices (like 100+ Zigbee devices) then I would recommend not waiting and instead just buying a separate dedicated Zigbee USB adapter today, then I still recommend you buy this official Home Assistant SkyConnect USB Stick when it becomes available but just use it as a dedicated adapter for only Thread/Matter, or alternatively wait and buy two of these official Home Assistant SkyConnect USB Sticks and use them separately as two dedicated single-protocol radio adapters for the different wireless protocols. As with existing Zigbee USB adapters being good as they already are no need to wait for an all-in-one multiprotocol combination adapter if you plan on building a large Zigbee network when a multiprotocol is likely to not perform as well, (again, on paper at least).

Anyway, suggest users who think they might connect 100+ Zigbee devices someday should consider just buying a separate dedicated Zigbee adapter now to use only for Zigbee devices. Most such dedicated Zigbee adapters should not become e-waste because it will probably be possible to migrate your Zigbee network to a new Zigbee adapter and then most modern dedicated Zigbee adapters can usually be flashed with alternative Zigbee Router firmware and repurposed as a Zigbee Router device (Zigbee network mesh signal repeater). Regardless, you will normally want many good always-on Zigbee Router devices in your Zigbee network mesh to achieve the best possible stable Zigbee environment.

Refrence agners and grobasoz comments → https://github.com/grobasoz/zigbee-firmware/issues/27

grobasoz comment: “Now to the big issue I have with Multiprotocol - and my personal opinion only. A “normal” Zigbee Coordinator on a “significant” network (ie 100+ devices) actually spends quite a bit of radio time managing the network, let alone handling the device messaging.

agners reply: “Agreed, I think the multiprotocol solution might not be for large networks. A person with that many devices, likely will have multiple coordinator/border router capable 802.15.4 radios in the house already :sweat_smile: It is mainly a good solution for new users: People don’t have to choose between Thread and Zigbee at the start, they can mix and match. For power users Thread and Zigbee networks on separate channels definitely make sense (along with dedicated radios). That said, I like the concept of having a rather dumb radio and most of the protocol on the host. So it still might make sense to have the (Multi-)PAN firmware running along with zigbeed on the host. We’ll see how well that works in practice.

PS: Personally I will buy at least two of these official Home Assistant SkyConnect USB Sticks myself and only use one protocol per adapter just to sponsor the Home Assistant founders and Nabu Casa.


Does anyone know if it is possible to turn off zigbee and just have thread on SkyConnect? I already have my zigbee network working perfectly so I am not keen on introducing another zigbee signal into the mix.

I plan on substiututing my current zigbee stick, with this one

That will certenly be possible by simply not using it for Zigbee and then it will use activate the Zigbee part for it.

I read now however that they will initially only ship it with Zigbee support, and that Thread support will come later via firmware and software updates.

That is how I plan on using one, though I am planing on buying two and using one dedicated for Zigbee and one dedicated for Thread.

I’ve not used a multi protocol stick so I’m not sure what the capabilities are. I’ll wait and see I guess.

About the USB dongle capacit to manage devices, the USB3.0 sonoff is capable of managing several dozens of devices. It was the reason for to migrate from the Sonoff bridge (wifi connected) to the dongle - I’ve more than 70 devices.
Is there any limit on number of devices the dongle will be capable to manage ?

Yes, I also want to purchase it but will await for reviews to see how well it works for Zigbee and Thread coverage and how many devices it can handle. But it looks really great on paper

And maybe more international sellers…

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I would hope that we’d eventually be able to use Zigbee2MQTT with this stick. Would there be any reason that couldn’t be possible?

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Home Assistant SkyConnect USB Stick pre-order is now available at a few selected resellers globally!


Their webpage not only says that it will support the ZHA integration for Zigbee but also mentions Zigbee2MQTT compatibility as well, though it does not currently warn or mention there that Z2M support for EZSP based adapters is still in “beta” development stage because even though it has matured since implemented last year it does not quite yet have feature parity with Zigbee2MQTT support for ZNP adapters (e.i. Texas Instrument CC2652/CC1352 based adapters), as most notably Zigbee2MQTT’s EZSP adapter support is missing the backup/restore and ZGP (Zigbee Green Power) feature support, however, this fact being lifted up will hopefully lead to more testers and developers helping the Zigbee2MQTT/IoBroker/zigbee-herdsman developer working on EZSP adapter support by finding/reporting bugs and testing or improving new code for it, see → https://github.com/Koenkk/zigbee-herdsman/issues/319

@agners Do I understand correctly that by default the Home Assistant SkyConnect USB Stick will initially only ship with a standard EmberZNet Zigbee NCP firmware image and not an RPC firmware?

Do we have any information that SkyConnect will be support BLE from the beginning or in the future?

Zigbee + Thread are the same radio (IEEE 802.15.4) with different addressing.

BTLE is a completely different technology.

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Yes, I know that but I ask because SoC scpecification give us information that he support BLE 5.0.

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I asked and while ÉFR32MG21 based hardware could maybe technically act as a (dedicated) Bluetooth adapter with an independently built/compiled custom firmware image from the community got a reply that Nabu Casa / Home Assistant founders will not at this time be looking into providing Bluetooth firmware images for it, see related discussion → Bluetooth controller firmware for EFR32MGxx compatible with Home Assistant's new native Bluetooth integration? · Issue #31 · grobasoz/zigbee-firmware · GitHub

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Thanks for the datasheet extract - it explains the question which initially looked odd. My Bad!

My understanding is Matter/ Thread SoC have Bluetooth radios for initial client device provisioning (pairing / key exchange with a phone) rather than for on-going support for multiple real-time protocols.

NabuCasa Yellow has a “SilLabs IoT Accelerator” logo on it which this hard-bitten engineer reads as marketing speak for “this is Beta, but we are working on it”!

The 2022.10 release party video gave me the impression that getting Zigbee and Thread radios to interleave both low-level real-time protocols on the uP AND communicate via USB to two separate software protocol stacks was rather a challenge - and partly the reason for launch with Zigbee only.

Taken together, my guess would be Zigbee + Thread + BTLE at the same time still seems very unlikely, but firmware will get optimised over time to support larger numbers of client devices.

Same chipset at the HA Yellow which I am running Z2M on so no reason to think you couldn’t run SkyConnect with Z2M.

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