Circuit Documentation

Summary

This circuit involves an ESP32 microcontroller interfacing with various sensors and components, including a light sensor (BH1750), a pressure sensor (BMP280), a real-time clock (DS3231 RTC), a temperature sensor (DS18B20), multiple 8x8 LED matrices (MAX7219), and a few passive components like resistors and LEDs. The circuit is powered via a USB power source.

Component List

1. ESP32 Mini

   • Description: A powerful microcontroller with Wi-Fi and Bluetooth capabilities.
   • Pins: GND, GPIO27, GPIO25, GPIO32, TDI, GPIO4, GPIO0, GPIO2, SD1, CLK, RXD, TXD, GPIO22, GPIO21, GPIO17, GPIO16, VCC, TD0, SD0, RST, SVP, GPIO26, GPIO18, GPIO19, GPIO23, GPIO5, 3.3V, TCK, SD3, NC, SVN, GPIO35, GPIO33, GPIO34, TMS, SD2

2. BH1750

   • Description: A digital light sensor.
   • Pins: VCC, GND, SCL, SDA, ADDR

3. BMP280

   • Description: A digital pressure sensor.
   • Pins: VCC, GND, SCL, SDA, CSB, SDO

4. DS3231 RTC

   • Description: A real-time clock module.
   • Pins: 32K, SQW, SCL, SDA, VCC, GND

5. DS18B20

   • Description: A digital temperature sensor.
   • Pins: VDD, DQ, GND

6. USB Power

   • Description: Provides power to the circuit.
   • Pins: +, -

7. MAX7219 8x8 LED Matrix

   • Description: An 8x8 LED matrix display.
   • Pins: CS, CLK, DIN, GND, VCC, CS(OUT), CLK(OUT), DOUT, VCC(OUT)

8. Resistor (2200 Ohms)

   • Description: A resistor with 2200 Ohms resistance.
   • Pins: pin1, pin2

9. Resistor (500 Ohms)

   • Description: A resistor with 500 Ohms resistance.
   • Pins: pin1, pin2

10. Resistor (50000 Ohms)

    • Description: A resistor with 50000 Ohms resistance.
    • Pins: pin1, pin2

11. LED: Two Pin (green)

    • Description: A green LED.
    • Pins: cathode, anode

12. Black Panel Mount 4mm Banana Socket

    • Description: A black panel mount socket.
    • Pins: Black_Pin

13. bc547

    • Description: A general-purpose NPN transistor.
    • Pins: collector, base, Emitter

Wiring Details

ESP32 Mini

• GPIO32 connected to Black Panel Mount 4mm Banana Socket (Black_Pin)
• GPIO22 connected to DS3231 RTC (SDA), BH1750 (SDA), BMP280 (SDA)
• GPIO21 connected to DS3231 RTC (SCL), BH1750 (SCL), BMP280 (SCL)
• GND connected to bc547 (Emitter), MAX7219 8x8 LED Matrix (GND) x4, DS18B20 (GND), USB power (-), DS3231 RTC (GND), BH1750 (GND), BMP280 (GND)
• VCC connected to MAX7219 8x8 LED Matrix (VCC) x4, USB power (+), LED: Two Pin (green) (anode)
• GPIO18 connected to MAX7219 8x8 LED Matrix (CLK) x4
• GPIO19 connected to DS18B20 (DQ) via Resistor (2200 Ohms) (pin2)
• GPIO23 connected to MAX7219 8x8 LED Matrix (DIN)
• GPIO5 connected to MAX7219 8x8 LED Matrix (CS) x4
• 3.3V connected to DS18B20 (VDD) via Resistor (2200 Ohms) (pin1), DS3231 RTC (VCC), BH1750 (VCC), BMP280 (VCC)
• GPIO33 connected to Resistor (50000 Ohms) (pin1)

BH1750

• SDA connected to ESP32 Mini (GPIO22), DS3231 RTC (SDA), BMP280 (SDA)
• SCL connected to ESP32 Mini (GPIO21), DS3231 RTC (SCL), BMP280 (SCL)
• GND connected to ESP32 Mini (GND), bc547 (Emitter), MAX7219 8x8 LED Matrix (GND) x4, DS18B20 (GND), USB power (-), DS3231 RTC (GND), BMP280 (GND)
• VCC connected to ESP32 Mini (3.3V)

BMP280

• SDA connected to ESP32 Mini (GPIO22), DS3231 RTC (SDA), BH1750 (SDA)
• SCL connected to ESP32 Mini (GPIO21), DS3231 RTC (SCL), BH1750 (SCL)
• GND connected to ESP32 Mini (GND), bc547 (Emitter), MAX7219 8x8 LED Matrix (GND) x4, DS18B20 (GND), USB power (-), DS3231 RTC (GND), BH1750 (GND)
• VCC connected to ESP32 Mini (3.3V)

DS3231 RTC

• SDA connected to ESP32 Mini (GPIO22), BH1750 (SDA), BMP280 (SDA)
• SCL connected to ESP32 Mini (GPIO21), BH1750 (SCL), BMP280 (SCL)
• GND connected to ESP32 Mini (GND), bc547 (Emitter), MAX7219 8x8 LED Matrix (GND) x4, DS18B20 (GND), USB power (-), BH1750 (GND), BMP280 (GND)
• VCC connected to ESP32 Mini (3.3V)

DS18B20

• GND connected to ESP32 Mini (GND), bc547 (Emitter), MAX7219 8x8 LED Matrix (GND) x4, USB power (-), DS3231 RTC (GND), BH1750 (GND), BMP280 (GND)
• DQ connected to ESP32 Mini (GPIO19) via Resistor (2200 Ohms) (pin2)
• VDD connected to ESP32 Mini (3.3V) via Resistor (2200 Ohms) (pin1)

USB Power

• - connected to ESP32 Mini (GND), bc547 (Emitter), MAX7219 8x8 LED Matrix (GND) x4, DS18B20 (GND), DS3231 RTC (GND), BH1750 (GND), BMP280 (GND)
• + connected to ESP32 Mini (VCC), MAX7219 8x8 LED Matrix (VCC) x4, LED: Two Pin (green) (anode)

MAX7219 8x8 LED Matrix

• GND connected to ESP32 Mini (GND), bc547 (Emitter), USB power (-), DS18B20 (GND), DS3231 RTC (GND), BH1750 (GND), BMP280 (GND)
• VCC connected to ESP32 Mini (VCC), USB power (+), LED: Two Pin (green) (anode)
• CLK connected to ESP32 Mini (GPIO18)
• DIN connected to ESP32 Mini (GPIO23)
• CS connected to ESP32 Mini (GPIO5)
• DOUT connected to **MAX7219