This is an open source project dedicated to implementing the MDB (Multi-Drop Bus) protocol for cashless vending machines, using ESP32 as the main platform and KiCad for PCB design. The MDB protocol is widely used in vending machines for communication between devices, enabling integration with cashless payment systems.

• SIM7080G (LTE Cat-M / NB-IoT) for IoT connectivity and remote telemetry
• DEX interface (with voltage protection >3.3V) ensuring safe communication with legacy vending systems
• I2C bus for expansion and peripheral integration
• Pulse I/O interface for compatibility with traditional coin/bill systems
• Addressable RGB LED for real-time visual status indication (e.g., connectivity, errors, transactions)
• Buzzer for audible feedback and event signaling

This project is part of the VMFlow ecosystem, aiming to standardize and simplify the development of modern, connected vending solutions.

GitHub

https://github.com/nodestark/mdb-esp32-cashless

Youtube

https://www.youtube.com/shorts/wKaXX6SeWW8

VMflow

https://vmflow.xyz

Google Play

https://play.google.com/store/apps/details?id=xyz.vmflow.target