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Pinout

                              Pico 2 W
                          ┌───────────────┐
  Left Throttle    GP0 ←──┤ 1          40 ├── VBUS
  Left Reverse     GP1 ←──┤ 2          39 ├── VSYS ───── Step-down 5V (power in)
                   GND ←──┤ 3          38 ├── GND ────── Common GND / SD Card GND
  Right Throttle   GP2 ←──┤ 4          37 ├── 3V3_EN
  Right Reverse    GP3 ←──┤ 5          36 ├── 3V3 ────── SD Card 3V3
  DHT11 Data       GP4 ───┤ 6          35 ├── ADC_VREF
  Fan 1 Tach       GP5 ───┤ 7          34 ├── GP28
                   GND ───┤ 8          33 ├── GND
  Weapon           GP6 ───┤ 9          32 ├── GP27
  Fan 2 Tach       GP7 ───┤ 10         31 ├── GP26 ←──── Battery ADC
  LED Strip DIN    GP8 ───┤ 11         30 ├── RUN
                   GP9 ───┤ 12         29 ├── GP22
                   GND ───┤ 13         28 ├── GND
                  GP10 ───┤ 14         27 ├── GP21
                  GP11 ───┤ 15         26 ├── GP20
  IMU TX          GP12 ───┤ 16         25 ├── GP19 ←──── SD Card MOSI (SPI0)
  IMU RX          GP13 ───┤ 17         24 ├── GP18 ←──── SD Card CLK  (SPI0)
                   GND ───┤ 18         23 ├── GND
  Fan 1 PWM       GP14 ───┤ 19         22 ├── GP17 ←──── SD Card CS   (SPI0)
  Fan 2 PWM       GP15 ───┤ 20         21 ├── GP16 ←──── SD Card MISO (SPI0)
                          └───────────────┘

Pin Assignment Summary

GPIO	Function	Peripheral	Status
GP0	Left Motor Throttle	PWM Slice 0A	Wired
GP1	Left Motor Reverse	PWM Slice 0B	Wired
GP2	Right Motor Throttle	PWM Slice 1A	Wired
GP3	Right Motor Reverse	PWM Slice 1B	Wired
GP4	DHT11 Temp/Humidity	GPIO	Planned
GP5	Fan 1 Tach (RPM)	GPIO Input	Planned
GP6	Weapon Motor	PWM Slice 3A	Planned
GP7	Fan 2 Tach (RPM)	GPIO Input	Planned
GP8	WS2812B LED Strip DIN	PIO	Planned
GP14	Fan 1 PWM	PWM Slice 7A	Planned
GP15	Fan 2 PWM	PWM Slice 7B	Planned
GP12	IMU TX	UART0 TX	Planned
GP13	IMU RX	UART0 RX	Planned
GP16	SD Card MISO	SPI0 RX	Planned
GP17	SD Card CS	SPI0 CSn	Planned
GP18	SD Card CLK	SPI0 SCK	Planned
GP19	SD Card MOSI	SPI0 TX	Planned
GP26	Battery Voltage	ADC0	Planned

ESC Wiring

Each bidirectional ESC has 3 wires:

• Signal (white/yellow) → Connect to GPIO pin (two signals per ESC: throttle + reverse)
• Ground (black/brown) → Connect to Pico GND
• Power (red) → Leave disconnected (ESCs powered directly from battery)

WS2812B LED Strip (~75 LEDs, ~50 inches)

Strip Wire	Wire To
DIN	GP8 (Pin 11)
+5V	Step-down 5V output (direct)
GND	Common GND (shared with Pico)

⚠️ Do NOT power the strip through the Pico — wire 5V directly from the LM2596S step-down output. Brightness capped at 50% in software to stay within the step-down's 3A limit.

Noctua NF-A4x10 5V PWM Fans

Fan Wire	Fan 1 → Pico	Fan 2 → Pico
+5V (yellow)	VSYS (Pin 39)	VSYS (Pin 39)
GND (black)	GND	GND
PWM (blue)	GP14 (Pin 19)	GP15 (Pin 20)
Tach (green)	GP5 (Pin 7)	GP7 (Pin 10)

Both fans on PWM Slice 7 (25kHz) — independent duty cycles, shared frequency. Tach outputs ~2 pulses per revolution.

DHT11 Temperature/Humidity Sensor

DHT11 Pin	Pico Pin
VCC	3V3 (Pin 36)
DATA	GP4 (Pin 6)
GND	GND

SD Card Module Wiring

Module Pin	Pico Pin
3V3	3V3 (Pin 36)
CS	GP17 (Pin 22)
MOSI	GP19 (Pin 25)
CLK	GP18 (Pin 24)
MISO	GP16 (Pin 21)
GND	GND (Pin 38)

Power

• 3S LiPo (11.1V nominal) powers ESCs directly
• Step-down converter takes battery voltage → 5V into VSYS (pin 39)
• Pico's onboard regulator converts 5V → 3.3V for logic and peripherals