Circuit Documentation

Summary

This document provides a detailed overview of a circuit that includes a Raspberry Pi Pico microcontroller, various sensors, a microphone, an amplifier, and a loudspeaker. The circuit is designed to interface with multiple sensors and output audio signals through a loudspeaker.

Component List

1. Raspberry Pi Pico

   • Description: A microcontroller board based on the RP2040 microcontroller chip.
   • Pins: pin 1, pin 2, pin 3, pin 4, pin 5, pin 6, pin 7, pin 8, pin 9, pin 10, pin 11, pin 12, pin 13, pin 14, pin 15, pin 16, pin 17, pin 18, pin 19, pin 20, pin 21, pin 22, pin 23, pin 24, pin 25, pin 26, pin 27, pin 28, pin 29, pin 30, pin 31, pin 32, pin 33, pin 34, pin 35, pin 36, pin 37, pin 38, pin 39, pin 40, pin 41, pin 42, pin 43

2. BME/BMP280

   • Description: A combined digital humidity, pressure, and temperature sensor.
   • Pins: GND, SCL, SDA, VIN

3. INMP441 FRONT MIC

   • Description: A high-performance, low-power, digital-output, omnidirectional MEMS microphone.
   • Pins: L/R, WS, SCK, SD, VDD, GND

4. Adafruit MAX98357A

   • Description: A digital I2S audio amplifier breakout board.
   • Pins: VIN, GND, SD_MODE, GAIN, DIN, BCLK, LRCLK, VO+, VO-

5. Loudspeaker

   • Description: A device that converts electrical signals into sound.
   • Pins: pin1, pin2

6. MAX31865

   • Description: A RTD-to-Digital converter for platinum resistance temperature detectors.
   • Pins: F +, RTD +, RTD -, F -, VIN, GND, 3V3, CLK, SDO, SDI, CS, RDY

7. VL53L0X

   • Description: A time-of-flight distance sensor.
   • Pins: VIN, GND, SCL, SDA

8. Hall Sensor

   • Description: A sensor that detects the presence of a magnetic field.
   • Pins: -, +, S

9. Heatpad + pt100

   • Description: A heating pad combined with a PT100 temperature sensor.
   • Pins: TBD HP, TBD PT100

Wiring Details

Raspberry Pi Pico

• pin 4: No connection
• pin 5: No connection
• pin 6: No connection
• pin 7: Connected to Hall Sensor (S)
• pin 9: Connected to Adafruit MAX98357A (BCLK)
• pin 10: Connected to Adafruit MAX98357A (DIN)
• pin 11: Connected to Adafruit MAX98357A (LRCLK)
• pin 14: Connected to VL53L0X (SDA)
• pin 15: Connected to VL53L0X (SCL)
• pin 16: Connected to BME/BMP280 (SDA)
• pin 17: Connected to BME/BMP280 (SCL)
• pin 21: Connected to MAX31865 (SDO)
• pin 22: Connected to MAX31865 (CS)
• pin 24: Connected to MAX31865 (CLK)
• pin 25: Connected to MAX31865 (SDI)
• pin 36: Connected to INMP441 FRONT MIC (VDD), MAX31865 (3V3), BME/BMP280 (VIN), Adafruit MAX98357A (VIN), VL53L0X (VIN), Hall Sensor (+)
• pin 38: Connected to INMP441 FRONT MIC (GND), MAX31865 (GND), BME/BMP280 (GND), Adafruit MAX98357A (GND), VL53L0X (GND), Hall Sensor (-)

BME/BMP280

• GND: Connected to Raspberry Pi Pico (pin 38)
• SCL: Connected to Raspberry Pi Pico (pin 17)
• SDA: Connected to Raspberry Pi Pico (pin 16)
• VIN: Connected to Raspberry Pi Pico (pin 36)

INMP441 FRONT MIC

• GND: Connected to Raspberry Pi Pico (pin 38)
• VDD: Connected to Raspberry Pi Pico (pin 36)

Adafruit MAX98357A

• VIN: Connected to Raspberry Pi Pico (pin 36)
• GND: Connected to Raspberry Pi Pico (pin 38)
• BCLK: Connected to Raspberry Pi Pico (pin 9)
• DIN: Connected to Raspberry Pi Pico (pin 10)
• LRCLK: Connected to Raspberry Pi Pico (pin 11)
• VO+: Connected to Loudspeaker (pin2)
• VO-: Connected to Loudspeaker (pin1)

Loudspeaker

• pin1: Connected to Adafruit MAX98357A (VO-)
• pin2: Connected to Adafruit MAX98357A (VO+)

MAX31865

• GND: Connected to Raspberry Pi Pico (pin 38)
• 3V3: Connected to Raspberry Pi Pico (pin 36)
• CLK: Connected to Raspberry Pi Pico (pin 24)
• SDO: Connected to Raspberry Pi Pico (pin 21)
• SDI: Connected to Raspberry Pi Pico (pin 25)
• CS: Connected to Raspberry Pi Pico (pin 22)
• F +: Connected to MAX31865 (RTD +), Heatpad + pt100 (TBD PT100)
• RTD +: Connected to MAX31865 (F +), Heatpad + pt100 (TBD PT100)
• RTD -: Connected to MAX31865 (F -), Heatpad + pt100 (TBD PT100)
• F -: Connected to MAX31865 (RTD -), Heatpad + pt100 (TBD PT100)

VL53L0X

• VIN: Connected to Raspberry Pi Pico (pin 36)
• GND: Connected to Raspberry Pi Pico (pin 38)
• SCL: Connected to Raspberry Pi Pico (pin 15)
• SDA: Connected to Raspberry Pi Pico (pin 14)

Hall Sensor

• -: Connected to Raspberry Pi Pico (pin 38)
• +: Connected to Raspberry Pi Pico (pin 36)
• S: Connected to Raspberry Pi Pico (pin 7)

Heatpad + pt100

• TBD PT100: Connected to MAX31865 (F +), MAX31865 (RTD +), MAX31865 (RTD -), MAX31865 (F -)

Code Documentation

Raspberry Pi Pico Code

sketch.ino

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

documentation.txt

This document provides a comprehensive overview of the circuit, including the components used, their connections, and the code running on the Raspberry Pi Pico microcontroller.