MDB-USB Interface
Qibixx offers 2 MDB-USB Interfaces:
- MDB-USB Standard
- MDB-USB Ultra
They are used to connect a USB capable device (such as a PC, Raspberry Pi etc) to the MDB Bus.
Summary:
- Universal MDB to USB Interface;
- USB supported by Windows, Linux and MacOS;
- MDB Master and MDB Slave; Supports both functions concurrently;
- Precise, time-stamped sniffing from the MDB Bus;
- High-level, easy to implement serial interface protocol;
Specifications (MDB-USB Standard):
- USB 2.0 Interface;
- Dual MDB Connectors with Master and Slave functions;
- No power-supply necessary (USB Powered - 5V);
- 4 LED function indicators - Master (TX & RX) and Slave (TX & RX);
- Firmware update capable (via USB);
Specifications (MDB-USB Ultra):
- USB 2.0 Interface;
- Dual MDB Connectors with Master and Slave functions;
- 2 Relay Outputs controllable via Auto Mode;
- Power Output (USB-A Socket) from MDB 5V, 3A, non-isolated;
- RS-232 Interface (for special applications);
- I/O For Auto Mode
Common Use Cases
Connect the MDB-Cable in Master Port when the MDB is used as a Master(VMC) or Sniffer in the Bus.
Connect the MDB-Cable in Slave Port when the MDB is used as a Slave in the Bus.
The MDB interface can be configured to work as a Slave or a Master on the MDB bus (further details on what Master and Slave means in this context can be found in Master (VMC) Modes , Slave (Peripheral) Modes and in deeper detail in MDB specification). This means that the interface can be used to connect a commercial peripheral such a Cashless Reader to the bus or connect a computer running software to act as a Master/VMC (Vending Machine Controller), for instance. In addition, the device is also capable of "listening" to all messages that flow in the bus, without interfering, i.e. Sniffing the bus. The MDB Connections of the 3 Modes can be found hereafter.
Master/VMC Mode
MDB Interface connected as a Master (VMC)
In the example above the MDB-USB Interface is connected as a bus Master. In this case, the Interface is usually connected via USB to a host (such as a PC or Raspberry Pi) that handles the logic to operate the vending machine according to the messages received in the MDB bus. Note that to enable "Master" mode, it is necessary to configure the Connectors & Jumpers - MDB USB Plus accordingly.
You have a video game running on a PC that needs to be pre-paid to play for a given amount of time. In this case it would be necessary to have a Software program on the Computer that would communicate with the MDB interface and when the credit is available, launch the video game.
Slave/Peripheral Mode
Now, in this example, the MDB-USB Interface is connected to the bus as a "Slave". This would be useful if you have a vending machine that supports a given payment method (the coin acceptor in this example) and want to add a new one , like a Cashless Reader or a bill acceptor.
In the first case, all you need is the MDB interface configured to work as a Slave and connect it to the "Master" port, since when in "Slave" mode, this port is just forwarding the messages received in the "Slave" port (please see instructions to configure "Master" and "Slave" modes in Connectors & Jumpers - MDB USB Plus or Connector & Jumpers - MDB USB Ultra in case you acquired the MDB Ultra).
Sniffer Mode
It is important to connect the MDB Cable to the Master/VMC port of the MDB USB interface, otherwise, the sniffing will not be able to detect messages coming from the Peripheral(Coin Acceptors, Cashless and Bill Acceptors) to the VMC.
In the Example above, the Device is merely listening to messages in the bus. This feature combined with software intelligence, can be used for designing telemetry solutions, and most importantly, troubleshoot your own solutions.