ESP32 Development Board For IOT Attendance Projects

 ESP32 Development Board for IoT based RFID Attendance System 

Board Features:
Header for ESP32 Module

Header for 0.96” OLED Display Connected to I2C pins of ESP32 (D22,D21)

Header for RC522 Module. Connected to SPI pins of ESP32 (D2,D18,D23,D19,D5)

Relay Circuit to control heavy loads like (Solenoid Lock, Lamps, Alarm, Valve) Connected to D13

Two general usage LED(RED,Blue) connected to D12 ,D14

Sound Buzzer with Transistor driver as a buffer connected to D27

Push button connected to D26 (should use the internal pull up resistance in ESP32)

Free GPIO header for other external modules or components connections (D25,D33,D32,D35,D34)

SD card memory socket connected to SPI pins (D4,D23,D18,D19)

built in 3.3V voltage regulator to supply suitable current for all inboard peripherals

DS1307 RTC circuit with CR2032 battery holder mounted onboard connected to I2C pins (D22,D21)

RS485 interface chip onboard and A,B pins brought out by two method options (3pin Screw terminals , RJ45 dual connector) 

the chip SP485 selected as it powered by 3.3V and an automatic data direction select circuit is built so only two pins(UART0) used to communicate via RS485 which can be connected and disconnected via two pin jumper.

also there is an onboard solderable jumper to select and deselect the 120 ohm bus Terminal resistance 

DC Jack for power up the whole board with ordinary 5V adapter

Note: the RFID,OLED,ESP32 sold separatly .