What is MDB?

MDB (Multi-Drop Bus) is a standard from the 80’s for connecting peripherals such as bill acceptors, coin dispensers and credit card terminals inside vending machines to the master MDB device, the Vending Machine Controller (VMC): The technology used is robust and time proven, but not compatible with USB, serial or network interfaces. It uses a different electrical interface and 9 bit data. In addition, very quick answers are required, hard to achieve with generic computers. The MDB interfaces presented here solve that problem and allow a very easy and reliable connection between a vending machine with MDB bus interface and computers of all kinds.

Learn more about MDB

MDB Explained
MDB Master
MDB Slave
Logging and Debugging MDB


Qibixx is the leading manufacturer of innovative MDB Interfaces and applications

MDB Master

  • Connect MDB credit card terminal to Raspberry Pi
  • Connect MDB company card reader to PC
  • Build vending machine with Windows, Linux or Mac Computer

MDB Slave

  • Emulate a Cashless device
  • Get EVA-DTS Files from VMC
  • Build a mobile payment solution
  • Build a communications Gateway

MDB Sniffing

  • Analyse the MDB Bus to find issues and problems
  • Get telemetry on sales and payments
  • Analyse MDB traffic to monitor cash and product levels

MDB to USB Interface by Qibixx
MDB to USB Interface by Qibixx

MDB Products

Check out our product line and see how we implement modern payment systems on vending applications
MDB to USB Interface by Qibixx

MDB-USB Interface

The MDB-USB Interface by Qibixx is a MDB to USB converter. It connects the vending machine controller (VMC) to Multi Drop Bus controlled devices and works driverless on Linux, Mac and Windows.

It also features Master and Slave functions making it possible to fit cashless systems to your vending machine or sniffing the MDB Bus to get data and telemetry.

  • USB communication
  • MDB Protocol communication
  • RS232 (Serial)
  • 1 Relay
  • USB Host capable


The MDB Pi Hat is a reliable MDB extension to use with the Raspberry Pi or other devices with a compatible port.
It provides Master, Peripheral/Slave and Sniffing capabilities and its firmware can be updated from the Pi Interface.

  • High level functional interface for cashless device implementations;
  • Independent Master and Peripheral interfaces;
  • Jumperless configuration and operation;
  • Firmware update capable;
  • Universal MDB Interface in Pi Hat form factor;
  • Serial and SPI host interface capabilities;
  • Precise, time-stamped sniffing from MDB bus;
  • High-level, easy to implement serial interface protocol;
MDB Pi HAT by Qibixx

MDB Toolchest by Qibixx

MDB Toolchest

The MDB Toolchest is a Java-based Software Application which serves as an invaluable tool for diagnosing, simulating and testing MDB Peripherals or VMC’s.

The Software can accurately catch and decode MDB Communications when paired with the MDB-USB Interface. Sub-millisecond time stamps allow to understand exactly which block had been sent by whom on the MDB Bus.

Various simulation functions allow the MDB Toolchest to impersonate a VMC or a Peripheral for testing purposes.

  • Universal MDB Test, Local or Remote Sniffing and Simulation
  • Written in Java, platform independent
  • MDB Master and MDB Slave simulation support
  • Precise, time-stamped sniffing from the MDB Bus
  • Software can read Bonusdata capture files
  • Able to update the firmware of the MDB-USB Interface (Standard and Plus versions supported)
  • One-time license
  • License tied to the MDB-USB Interface: the software can be used on a unlimited number of computers for file analysis or capture with the licensed hardware
  • Works with MacOS, Windows and Linux


Paynino is a simple, easy to use, solution based on a low power CPU board for vending interfacing applications.

It is perfect for Arduino-based vending machines as it has a 4 pin/line protocol which is robust and easy to implement.

By interfacing with the MDB Pi HAT it offers a range of possibilities for payment applications, which rely on the MDB Protocol:

  • Activate a relay with payment (useful for carousel-like machines)
  • Give credit to a VMC via Web Request;
  • Request credit to a payment peripheral;
  • and much more…

Paynino includes:

  • Paynino Board
  • MDB Pi HAT
  • Aluminium Case
Paynino by Qibixx


    Do you have any Questions ?
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