Circuit Documentation

Summary

This document provides a detailed overview of a circuit that integrates an ESP32 microcontroller, an RFID-RC522 module, a Membrane Matrix Keypad, and an R307 Fingerprint Sensor. The circuit is designed to interface these components for various input and identification purposes.

Component List

1. ESP32

   • Description: A powerful microcontroller with integrated Wi-Fi and Bluetooth capabilities.
   • Pins: EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, GND, VIN, 3V3, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, RX0, TX0, D22, D23, BOOT

2. RFID-RC522

   • Description: A low-cost RFID reader module that operates at 13.56 MHz.
   • Pins: VCC (3.3V), RST, GND, IRQ, MISO, MOSI, SCK, SDA

3. Membrane Matrix Keypad

   • Description: A 4x3 matrix keypad used for user input.
   • Pins: Row 1, Row 2, Row 3, Row 4, Column 1, Column 2, Column 3

4. R307 Fingerprint Sensor

   • Description: A fingerprint sensor module used for biometric identification.
   • Pins: VCC, GND, TX, RX, Touch, 3.3V

Wiring Details

ESP32

• D33 connected to Membrane Matrix Keypad Column 3
• D25 connected to Membrane Matrix Keypad Column 2
• D26 connected to Membrane Matrix Keypad Column 1
• D27 connected to Membrane Matrix Keypad Row 4
• D14 connected to Membrane Matrix Keypad Row 3
• D12 connected to Membrane Matrix Keypad Row 2
• D13 connected to Membrane Matrix Keypad Row 1
• GND connected to R307 Fingerprint Sensor GND
• 3V3 connected to R307 Fingerprint Sensor VCC and 3.3V, and RFID-RC522 VCC (3.3V)
• GND connected to RFID-RC522 GND
• D4 connected to R307 Fingerprint Sensor Touch
• D5 connected to RFID-RC522 SDA
• D18 connected to RFID-RC522 SCK
• D19 connected to RFID-RC522 MISO
• RX0 connected to R307 Fingerprint Sensor TX
• TX0 connected to R307 Fingerprint Sensor RX
• D22 connected to RFID-RC522 RST
• D23 connected to RFID-RC522 MOSI

RFID-RC522

• VCC (3.3V) connected to ESP32 3V3
• RST connected to ESP32 D22
• GND connected to ESP32 GND
• SDA connected to ESP32 D5
• SCK connected to ESP32 D18
• MISO connected to ESP32 D19
• MOSI connected to ESP32 D23

Membrane Matrix Keypad

• Column 3 connected to ESP32 D33
• Column 2 connected to ESP32 D25
• Column 1 connected to ESP32 D26
• Row 4 connected to ESP32 D27
• Row 3 connected to ESP32 D14
• Row 2 connected to ESP32 D12
• Row 1 connected to ESP32 D13

R307 Fingerprint Sensor

• VCC connected to ESP32 3V3
• GND connected to ESP32 GND
• TX connected to ESP32 RX0
• RX connected to ESP32 TX0
• Touch connected to ESP32 D4
• 3.3V connected to ESP32 3V3

Code

No code is provided for this circuit.

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This document provides a comprehensive overview of the circuit, including the components used and their interconnections. This should serve as a useful reference for understanding and replicating the circuit.