Practical scenario – working with multiple communication protocols with ESP32
In this hands-on project, we’ll build an access control system using an MFRC522 RFID reader connected to an ESP32 microcontroller. This system will read, write, and register MIFARE 13.56 MHz RFID cards. When a scanned ID card matches any registered ID, the microcontroller will issue an MQTT publish message. This message instructs a remote MQTT subscriber, running on another ESP32 microcontroller, to activate the corresponding switch meant to enable door access. However, in this demonstration, we won’t connect to an actual switch. Instead, we’ll illuminate the built-in LED on the MQTT subscriber’s ESP32 microcontroller to simulate the process.
You will require the following materials:
- 2x ESP32 NodeMCU microcontroller
- 1x MFRC522 RFID card reader
- 1x push button (latch) switch
- 2x MIFARE 13.56 MHz RFID cards, fobs, or NFC cards
- Jumper cables
