Circuit Documentation

Summary of the Circuit

This circuit integrates an ESP8266 NodeMCU microcontroller with an OLED display and a TP4056 lithium-ion battery charging module to create a system capable of displaying information while being powered by a rechargeable 18650 Li-ion battery. The ESP8266 NodeMCU serves as the central processing unit, controlling the OLED display via I2C communication and managing power received from the TP4056 charger module. The TP4056 module is responsible for safely charging the 18650 Li-ion battery and providing a stable power supply to the microcontroller.

Component List

ESP8266 NodeMCU

• Microcontroller with WiFi capability
• Pins: D0, D1, D2, D3, D4, 3V3, GND, D5, D6, D7, D8, RX, TX, A0, RSV, SD3, SD2, SD1, CMD, SD0, CLK, EN, RST, VIN

OLED Display (128x32)

• Small display for showing text and graphics
• Pins: SDA, SCL, VCC, GND

TP4056

• Lithium-ion battery charging module
• Pins: OUT-, B-, B+, OUT+, IN-, IN+

18650 Li-ion Battery

• Rechargeable battery for power supply
• Pins: -, +

Wiring Details

ESP8266 NodeMCU

• D1 (SCL) connected to OLED Display SCL
• D2 (SDA) connected to OLED Display SDA
• GND connected to OLED Display GND and TP4056 OUT-
• 3V3 connected to OLED Display VCC
• VIN connected to TP4056 OUT+

OLED Display (128x32)

• SCL connected to ESP8266 NodeMCU D1
• SDA connected to ESP8266 NodeMCU D2
• GND connected to ESP8266 NodeMCU GND
• VCC connected to ESP8266 NodeMCU 3V3

TP4056

• OUT- connected to ESP8266 NodeMCU GND
• OUT+ connected to ESP8266 NodeMCU VIN
• B- connected to 18650 Li-ion Battery -
• B+ connected to 18650 Li-ion Battery +

18650 Li-ion Battery

• • (negative) connected to TP4056 B-
• • (positive) connected to TP4056 B+

Documented Code

Microcontroller: ESP8266 NodeMCU

File: sketch.ino

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

}

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

}

File: documentation.txt

(No additional documentation provided for the code)

This concludes the documentation for the given circuit. The circuit is designed to be powered by a rechargeable battery while displaying information on the OLED screen, with the ESP8266 NodeMCU controlling the display and managing power.