Visual diagram of the connections between the BBC micro:bit and the Maqueen Lite v4 carrier board. Every line is traced to a specific source reference in the
pxt-maqueen extension —
see pinout.html for the line-by-line evidence table.
Motors (PWM via I2C)4× RGB ambient (I2C)Servos S1/S2 (I2C)Simple LEDs (digital)Sensors (digital)Buzzer (PWM)I2C bus (P19/P20)
Reading this diagram
Visual element
What it represents
Filled coloured pin on the micro:bit's right edge
A micro:bit GPIO pin actually used by the Maqueen carrier (color matches the component it connects to)
Solid line between pin and component
A direct GPIO connection — single wire, single function
Purple I2C bus lines (P19/P20)
Shared two-wire bus reaching the motor driver IC and (dashed) the RGB array — multiplexed by I2C address
Blocks fanning out from the I2C 0x10 chip
Components controlled through the motor driver IC, addressed by register: M1, M2, S1, S2, RGB
Dashed-outline IR receiver block
Connected via a fixed pin internal to maqueenIR.cpp — not declared in the TypeScript layer
Free pins listed under the micro:bit
P3/P4/P6/P7/P9/P10/P15/P16 — available for kid add-ons (P3/4/6/7/9/10 share the LED matrix; disable display first)
What's not shown
The buzzer connection to P0 is shown but is a convention-only deduction — pxt-maqueen does not declare it. Maqueen Lite v4 wires the on-board buzzer to P0 following the standard micro:bit V2 speaker convention; this matches DFRobot's example sketches on the
product wiki.
The Gravity extension ports (P0, P1, P2) are not drawn separately — they share pins with the buzzer and ultrasonic. Plugging anything into them disables the on-board function on that pin. The future "Add-on" framework (ADDON:* verbs in firmware) will handle this conflict gracefully.