pxt-maqueen extension.maqueen.ts — maqueen.ts — line-by-line DigitalPin.PXX and I2C 0x10 references cited in the "How we know" section below.maqueenIR.cpp — maqueenIR.cpp — IR-receiver C++ shim. Pin is user-configurable via maqueenIR.initIR(pin); on Maqueen Lite v4 the on-board IR receiver is wired to P16.DigitalPin.PXX map to which physical edge-connector pad and which are shared with the LED matrix.pxt-maqueen is DFRobot's official MakeCode extension for the Maqueen family of educational robots (including Maqueen Lite v4). Add it in MakeCode by clicking Extensions → search "maqueen" or pasting its GitHub URL. It exposes a maqueen namespace that wraps the low-level pin and I2C operations behind kid-friendly block APIs:
maqueen.motorRun(motor, dir, speed) — drives the I2C motor controller at address 0x10.maqueen.motorStop(motor) — brake.maqueen.servoRun(servo, angle) — writes to I2C registers 0x14 (S1) and 0x15 (S2).maqueen.writeLED(led, switch) — toggles the simple LEDs on P8 (left) and P12 (right).maqueen.readPatrol(sensor) — reads the line-tracking sensors on P13 (left) and P14 (right).maqueen.Ultrasonic(unit) — drives P1 (trig) / P2 (echo) for SR04.maqueen.IR_read() — reads NEC codes from the on-board IR receiver via the maqueenIR.cpp C++ shim.0x32 of the same 0x10 chip — not standard NeoPixels.Maqueen Lab's v1 firmware (firmware/v1-maqueen-lib.ts) uses these maqueen.* calls directly. The future v2 firmware will replace them with raw pins.* and I2C calls — same wire protocol, same web app, lower-level code shown side-by-side in every Component Explorer for educational progression.
| Pin | Used by | Direction | Notes |
|---|---|---|---|
| P0 | Buzzer | Out (PWM) | Default music pin; also Gravity port — conflicts if reassigned |
| P1 | Ultrasonic TRIG | Out | Also labeled Gravity port — conflicts with ext sensor |
| P2 | Ultrasonic ECHO | In | Also labeled Gravity port — conflicts with ext sensor |
| P3 | — | free | Shared with LED matrix col1 (avoid for digital out) |
| P4 | — | free | LED matrix col2 |
| P5 | Button A | In | micro:bit built-in |
| P6 | — | free | LED matrix col9 |
| P7 | — | free | LED matrix col8 |
| P8 | LED Left (simple) | Out | Digital ON/OFF |
| P9 | — | free | LED matrix col7 |
| P10 | — | free | LED matrix col3 |
| P11 | Button B | In | micro:bit built-in |
| P12 | LED Right (simple) | Out | Digital ON/OFF |
| P13 | Line sensor Left | In | Digital 0/1 |
| P14 | Line sensor Right | In | Digital 0/1 |
| P15 | — | free | — |
| P16 | — | free | — |
| P19 | I2C SCL | — | Motor driver + 4× RGB + servos S1/S2 (addr 0x10) |
| P20 | I2C SDA | — | Same I2C bus |
| Component | Pin / Address | Notes |
|---|---|---|
| Motor driver | I2C 0x10 | Reg 0x00 = M1, 0x02 = M2 (direction + speed) |
| 4× RGB ambient lights | I2C 0x10, reg 0x32 | Not standard NeoPixel — chip-driven via the motor driver IC |
| LED Left (simple) | P8 digital | ON/OFF |
| LED Right (simple) | P12 digital | ON/OFF |
| Line sensor Left | P13 digital | 0 / 1 |
| Line sensor Right | P14 digital | 0 / 1 |
| Ultrasonic TRIG | P1 | SR04 / SR04P |
| Ultrasonic ECHO | P2 | SR04 / SR04P |
| Buzzer | P0 | micro:bit default music lib |
| Servos S1 / S2 | I2C 0x10 (via extension) | Use maqueen.servoRun(S1|S2, angle) |
| IR receiver | P16 (Maqueen Lite v4 default) | maqueenIR.initIR(Pins.P16) + per-button onPressEvent(...) |
| Register | Function |
|---|---|
0x00 | Motor M1 (left): direction + speed |
0x02 | Motor M2 (right): direction + speed |
0x14 | Servo S1 angle |
0x15 | Servo S2 angle |
0x32 | 4× RGB LED data (16M colors each) |
P3, P4, P6, P7, P9, P10, P15, P16
P3/P4/P6/P7/P9/P10 share the LED display matrix — disable display first if used as digital outputs:
led.enable(false)P0 = buzzer. Plugging anything else into the Gravity P0 port silences the buzzer (or vice versa).
P1 / P2 = ultrasonic. Plugging a Gravity sensor into P1 or P2 disables the ultrasonic. The app will warn when both are used.
I2C bus (P19/P20) is shared. Add-ons at addresses other than 0x10 are fine; address collision is fatal.
Every pin assignment below is extracted from the pxt-maqueen extension source. Line numbers refer to maqueen.ts at the time of writing.
| Pin / Address | Component | Evidence |
|---|---|---|
P1 | Ultrasonic TRIG | maqueen.ts:164 — pins.digitalWritePin(DigitalPin.P1, 1) inside Ultrasonic() |
P2 | Ultrasonic ECHO | maqueen.ts:172 — d = pins.pulseIn(DigitalPin.P2, PulseValue.High, 500 * 58) |
P8 | LED Left (simple) | maqueen.ts:287 — pins.digitalWritePin(DigitalPin.P8, ledswitch) inside writeLED(LEDLeft, ...) |
P12 | LED Right (simple) | maqueen.ts:289 — pins.digitalWritePin(DigitalPin.P12, ledswitch) inside writeLED(LEDRight, ...) |
P13 | Line sensor Left | maqueen.ts:267 — return pins.digitalReadPin(DigitalPin.P13) inside readPatrol(PatrolLeft) |
P14 | Line sensor Right | maqueen.ts:269 — return pins.digitalReadPin(DigitalPin.P14) inside readPatrol(PatrolRight) |
I2C 0x10 | Motor + RGB + Servos chip | maqueen.ts:19 — const MOTER_ADDRESSS = 0x10, used by pins.i2cWriteBuffer(0x10, buf) throughout |
I2C 0x10 reg 0x14 | Servo S1 angle | maqueen.ts:308 — buf[0] = 0x14 then pins.i2cWriteBuffer(0x10, buf) inside servoRun(S1, angle) |
I2C 0x10 reg 0x15 | Servo S2 angle | maqueen.ts:311 — buf[0] = 0x15 for S2 |
I2C 0x10 reg 0x00 | Motor M1 | maqueen.ts:202–205 — buf[0] = 0x00; ...; pins.i2cWriteBuffer(0x10, buf) inside motorRun(M1, ...) |
I2C 0x10 reg 0x02 | Motor M2 | maqueen.ts:208–211 — buf[0] = 0x02 for M2 |
I2C 0x10 reg 0x32 | 4× RGB ambient LEDs | maqueen.ts:659 — pins.i2cWriteNumber(I2CADDR, 0x32, NumberFormat.Int8LE) inside the RGB write block |
| IR receiver (P16) | NEC IR | maqueenIR.cpp defines the API but does not hardcode a pin — user must call maqueenIR.initIR(maqueenIR.Pins.P16). P16 is the convention for Maqueen Lite v4. |
P0 | Buzzer | Not in pxt-maqueen. Maqueen Lite v4 wires the on-board buzzer to P0, the micro:bit's default music library output. Confirmed by DFRobot's example sketches on the wiki and matches micro:bit V2's built-in speaker convention. |
P19 / P20 | I2C SCL / SDA | Not in pxt-maqueen. Standard micro:bit edge-connector I2C pins per tech.microbit.org/hardware/edgeconnector; pins.i2c* calls in pxt-maqueen use these by default. |
P5 / P11 | Button A / B | Not in pxt-maqueen. Built into the micro:bit board itself, not the Maqueen carrier. |
P3, P4, P6, P7, P9, P10 | LED matrix columns | Not in pxt-maqueen. Belong to the micro:bit's built-in 5×5 LED display; usable as digital I/O only after led.enable(false). |
To re-verify: clone the repo and grep for DigitalPin.P and 0x10:
git clone https://github.com/DFRobot/pxt-maqueen
grep -nE "DigitalPin\.|0x10|0x14|0x15|0x32" pxt-maqueen/maqueen.ts| Verb (over BLE) | micro:bit code |
|---|---|
M:L,R | maqueen.motorRun(M1, dir, |L|) + same for M2 |
STOP | maqueen.motorStop(All) |
LED:i,s | maqueen.writeLED(i, s) |
SRV:i,a | maqueen.servoRun(Si, a) |
BUZZ:f,ms | music.playTone(f, ms) |
LINE? | maqueen.readPatrol(L/R) → LINE:l,r |
DIST? | maqueen.Ultrasonic(cm) → DIST:cm |
IR? | maqueen.IR_read() → IR:code |
RGB:i,r,g,b | I2C write to 0x10 reg 0x32 |
| (auto) | input.acceleration(X/Y/Z) → ACC:x,y,z |
See firmware/v1-maqueen-lib.ts for the full implementation.
Phase 2 firmware (firmware/v2-raw-pins.ts) will replace maqueen.* calls with direct pins.* and pins.i2cWriteBuffer(...) operations — same wire protocol, lower-level code for advanced learners. The Component Explorers will show both versions side-by-side in the code panel.