Clone hubs (Mould King · CaDA · JieStar)
Battery hubs that Chinese brick brands put in their own sets — Mould King, CaDA, JieStar — with plugs and motors shaped to fit LEGO's, and all of them still on sale in 2026. They hear Bluetooth Low Energy at 2.4 GHz, and all but one hear it one way only: the controller rewrites an advertising payload over and over and the hub acts on whatever it hears, with no connection, no pairing and no bonding.
Reach
| Capability | State | Note |
|---|---|---|
| Mould King DIY module, 4 outputs | works, untested here | the exception in the family: an ordinary Bluetooth peripheral, connected like any hub, straight from the page |
| Mould King 6.0, 6 outputs | works | whole byte 0x00–0xFF centred on 0x80, so about ±127; driven by advertising, so it goes through the bridge |
| Mould King 4.0, 4 outputs | works, untested here | nibble, −7 to +7, stop 0x08 |
| Mould King 3.8, 5 outputs (4 plus 1 virtual) | works, untested here | nibble, −7 to +6, stop 0x09 |
| Mould King 5.0, 5 outputs (4 plus 1 virtual) | works, untested here | nibble, −7 to +7, stop 0x00 |
| CaDA Race Car, 3 outputs | works, untested here | drive, steer and lights; byte centred on 0x80 |
| JieStar SCM 4 and SCM 8, 4 and 8 outputs | works, untested here | nibble, −7 to +7, stop 0x00 |
| Three hubs of one family at once | works, untested here | Device 1, 2 and 3, cycled with the hub's own button, on MK 4.0, 6.0 and SCM 8; 3.8, 5.0 and SCM 4 hold one slot each |
| A 38 kHz Power Functions emitter | out of reach | the M-0006 and M-0019 boxes hold a 2.4 GHz receiver and no infrared receiver at all |
| Any advertising hub straight from a browser | out of reach | a browser is not permitted to advertise, which shuts the page out of the whole family by construction |
What it hears
Bluetooth, except that what travels is not really a Bluetooth message: a proprietary radio frame dropped at a known byte offset inside the advertising payload. The manufacturer IDs, the frame layout, the whitening and the one-off connect telegram are all in Third-party hubs over Bluetooth, and the DIY module sits in the same note as the plain case, with a service, a characteristic, four ports and a heartbeat.
The nibble hubs use the same −7 to +7 a Power Functions remote produces, so a speed value maps straight across with no rescaling.
"Power Functions" printed on a Mould King box is a claim about the plugs, not about the radio. The motors and connectors fit LEGO's first-generation Power Functions parts; the receiver hears nothing infrared. A set that looks like an 8879 remote with an 8884 receiver can be scrambled 2.4 GHz inside, and no infrared emitter will ever reach it.
Reaching it today
- The DIY module — from the page over Bluetooth, like any other hub. Nothing else needed.
- Mould King 6.0 — through the bridge, which can advertise.
- The rest of the family — anything that can advertise: the live forks of BrickController2 on a phone, or one of the open advertisers under Links.
Two things bite whatever does the advertising:
- Stop, then set, then start. Writing over a live advertising set never reaches the air, and the hub keeps running on the last payload it heard.
- Broadcasting does not mean unlimited hubs, it means fewer. A radio broadcasts one payload at a time. Three MK 4.0 hubs fit in one advertising set because their twelve channels share a single telegram; each MK 6.0 needs a set of its own. In practice you manage one or two.
Links
- Implemented only in the fork vicocz/brickcontroller2 — see BrickController2.
- Open-source advertisers: pink0D/MouldKingino · jrichter24/moldqueen.
- Prices are grey market: MK 6.0 (M-0019) about $40 in the West and $16 to $19 on AliExpress; MK 4.0 (M-0006) about €25.
- Frames, offsets and telegrams: Third-party hubs over Bluetooth. The other Bluetooth bricks: BuWizz · SBrick · Circuit Cubes.