Circuit Documentation

Summary

The circuit in question is designed to interface an ESP8266 NodeMCU microcontroller with a MAX30100 pulse oximeter sensor and a 0.96" OLED display. The ESP8266 NodeMCU serves as the central processing unit, controlling the OLED display via an I2C interface and reading data from the MAX30100 sensor, also through I2C. The MAX30100 sensor is used to measure blood oxygen saturation and heart rate, and the OLED display is used to present this data to the user.

Component List

MAX30100 Pulse Oximeter Sensor

• Description: A sensor used for measuring blood oxygen saturation (SpO2) and heart rate.
• Pins:
  • Vin: Power supply input
  • GND: Ground connection
  • SCL: I2C clock line
  • SDA: I2C data line
  • INT: Interrupt pin

0.96" OLED Display

• Description: A small display used for showing information such as sensor data.
• Pins:
  • GND: Ground connection
  • VDD: Power supply input
  • SCK: I2C/SPI clock line (used as I2C in this circuit)
  • SDA: I2C data line

ESP8266 NodeMCU

• Description: A microcontroller with Wi-Fi capabilities, used as the main controller in this circuit.
• Pins:
  • Digital I/O: D0 to D8
  • Analog Input: A0
  • Power: 3V3, GND, VIN
  • Serial: RX, TX
  • SPI: SD0, SD1, SD2, SD3, CMD, CLK
  • Reset and Enable: RST, EN

Wiring Details

MAX30100 Pulse Oximeter Sensor

• Vin connected to 3V3 on ESP8266 NodeMCU
• GND connected to GND on ESP8266 NodeMCU
• SCL connected to D1 on ESP8266 NodeMCU
• SDA connected to D2 on ESP8266 NodeMCU
• INT connected to D0 on ESP8266 NodeMCU

0.96" OLED Display

• GND connected to GND on ESP8266 NodeMCU
• VDD connected to 3V3 on ESP8266 NodeMCU
• SCK connected to D1 on ESP8266 NodeMCU (shared with MAX30100 SCL)
• SDA connected to D2 on ESP8266 NodeMCU (shared with MAX30100 SDA)

ESP8266 NodeMCU

• 3V3 provides power to MAX30100 Vin and OLED VDD
• GND connected to MAX30100 GND and OLED GND
• D1 (I2C SCL) connected to MAX30100 SCL and OLED SCK
• D2 (I2C SDA) connected to MAX30100 SDA and OLED SDA
• D0 connected to MAX30100 INT

Documented Code

No code was provided for the microcontroller. The documentation of the code would typically include a description of the functionality, setup, and main loop, along with comments explaining the purpose of each function and variable. Since no code is available, this section cannot be completed. If code becomes available, it should be added here with appropriate explanations and comments for maintainability and ease of understanding.