Open Play Brick rev B · emulator

The brick's real firmware, compiled to WebAssembly, wired to models of every chip on the board. Independent project, not affiliated with or endorsed by the LEGO Group.

Build one Source

Tag what the NFC reader sees

Unknown or non-play tag

Motion what the accelerometer feels

Sound what the microphone hears

It listens for loudness only. Nothing is recorded.

Colour held in front of the colour sensor

Another brick over the radio

sent 0 · received 0

Power

Speaker

Wiring drawn from the same netlist the firmware's pin header is generated from. Lines light up when something moves on them. Click a part or a wire.

Click a part to see what it is and why it was chosen.

Signals every pin, on the firmware's own clock

Jump to last

Scroll to zoom, drag to pan. Pause or Step first if you want to read individual bits.