| Pin | GPIO | Function | Our Use |
|---|---|---|---|
| 1 | GP0 | UART0 TX | Picoprobe Debugger TX |
| 2 | GP1 | UART0 RX | Picoprobe Debugger RX |
| 3 | GND | ||
| 4 | GP2 | I2C1 SDA | Display SDA |
| 5 | GP3 | I2C1 SCL | Display SCL |
| 6 | GP4 | GPIO Out | Stepper Sleep Signal |
| 7 | GP5 | GPIO In | Stepper Fault Signal |
| 8 | GND | ||
| 9 | GP6 | PWM 3A | Servo 0 |
| 10 | GP7 | PWM 3B | Servo 1 |
| 11 | GP8 | PWM 4A | Servo 2 |
| 12 | GP9 | PWM 4B | Servo 3 |
| 13 | GND | ||
| 14 | GP10 | PWM 5A | Servo 4 |
| 15 | GP11 | PWM 5B | Servo 5 |
| 16 | GP12 | PWM 6A | Servo 6 |
| 17 | GP13 | PWM 6B | Servo 7 |
| 18 | GND | ||
| 19 | GP14 | GPIO In | Stepper Endstop Low (0th position) |
| 20 | GP15 | GPIO In | Stepper Endstop High (maxSteps) |
| 21 | GP16 | GPIO Out | Stepper MS1 |
| 22 | GP17 | GPIO Out | CDC Active |
| 23 | GND | ||
| 24 | GP18 | GPIO Out | Stepper Address Line 0 |
| 25 | GP19 | GPIO Out | Stepper Address Line 1 |
| 26 | GP20 | GPIO Out | Stepper Address Line 2 |
| 27 | GP21 | GPIO Out | Stepper Mux Latch |
| 28 | GND | ||
| 29 | GP22 | GPIO In | DMX In |
| 30 | Run | Connect to ground to reset | |
| 31 | GP26 | GPIO Out | Stepper STEP Signal |
| 32 | GP27 | GPIO Out | Stepper DIR Signal |
| 33 | (A)GND | — | (Also the analog ground) |
| 34 | GP28 | GPIO Out | E-Stop Relay |
| 35 | ADC_VREF | Unused | |
| 36 | 3V3_OUT | ⚡️Power to the display | |
| 37 | 3V3_EN | ||
| 38 | GND | Ground Trace | |
| 40 | VSYS | 5V in, use a Schottky Diode | |
| 41 | VBUS | 🚌 |
Note: Servo pin mappings are defined in
controller-config.h
Power
From the docs:
Whilst it is possible to connect the Raspberry Pi’s 5V pin to the Raspberry Pi Pico VBUS pin, this is not recommended. Shorting the 5V rails together will mean that the Micro USB cannot be used. An exception is when using the Raspberry Pi Pico in USB host mode, in this case 5V must be connected to the VBUS pin. The 3.3V pin is an OUTPUT pin on the Raspberry Pi Pico, you cannot power the Raspberry Pi Pico via this pin, and it should NOT be connected to a power source.
(In other words, use VSYS 😅)