SD card module with Raspberry Pi Pico

Wiring for the SD card module (full size, SPI) on the Raspberry Pi Pico (RP2040, 3.3 V logic), chosen with the same pin rules BoardPilot uses: default buses first, and no pins that are used for flash, USB, the debugger or booting.

Wiring

SD card module pin	Role	Raspberry Pi Pico pin	Notes
GND	Ground	GND
3V3	Power	3V3(OUT)	Use 3V3 or 5V, not both
5V	Not wired to the board	not connected	Alternative 5 V input through the on-board regulator
CS	SPI chip select	GP17
MOSI	SPI MOSI	GP19
SCK	SPI clock	GP18
MISO	SPI MISO	GP16
GND2	Ground	GND

Check before you power it on

Supply: 3.3 V from the 3V3(OUT) pin.

Test code (Arduino)

// Library: SD (built in)
#include <SPI.h>
#include <SD.h>

void setup() {
  Serial.begin(115200);
  if (!SD.begin(17)) {
    Serial.println("No card: check wiring, the card format (FAT32) and power");
    return;
  }
  File f = SD.open("/test.txt", FILE_WRITE);
  f.println("Hello from the board");
  f.close();
  Serial.println("Wrote test.txt");
}

void loop() {}

Arduino board: rp2040:rp2040:rpipico. If the board is not found, hold the BOOTSEL button while plugging in the USB cable.

Questions

Which Raspberry Pi Pico pins do I use for the SD card module?

GND → GND, 3V3 → 3V3(OUT), CS → GP17, MOSI → GP19, SCK → GP18, MISO → GP16, GND2 → GND.

Does the SD card module work with the Raspberry Pi Pico at 3.3 V?

Yes: the SD card module runs at 3.3-5 V and the Raspberry Pi Pico uses 3.3 V signals, so no level shifting is needed.

BoardPilot checks this wiring in 3D as you build it, and finds crossed or missing wires on the real board.

Download BoardPilot

Full Raspberry Pi Pico pinout · SD card module (full size, SPI): all pins and data

The SD card module on other boards

ESP32 DevKit Arduino Mega 2560 R3 Arduino Nano Arduino Uno R3 WeAct Black Pill STM32F411CE ESP32-C3-DevKitM-1 ESP32-S3-DevKitC-1 Nordic nRF52840 DK NUCLEO-F401RE Raspberry Pi Pico 2 Raspberry Pi Pico W Teensy 4.1

Other parts on the Raspberry Pi Pico

BME280 BMP280 DHT22 DHT11 HC-SR04 SSD1306 OLED MPU6050 DS18B20 WS2812B LED strip SG90 servo Relay module HC-SR501 PIR LCD 1602 I2C INA219 VL53L0X BH1750 MAX30102 RC522 RFID NEO-6M GPS Capacitive soil moisture sensor ADS1115 TM1637 28BYJ-48 stepper L298N Potentiometer Push button LED Joystick module AHT20