Generic Master

Master Command Group

With the Master Commands, the interface can be used to implement or simulate a "Vending Machine Controller".

Any communication initiated with the following commands will send out on the "TX" line of the MDB interface, answers will be expected on the "RX" line.

The M command is used to start or stop Master Mode. On the Pi Hat interface starting Master Mode will automatically set the slave (RX) interface pull-up to active so that slaves can answer to the master.

Stopping Master Mode will disable the pull-up on the RX interface line.

Enable Generic Master
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Disable Generic Master
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Possible answers from the interface:

MDB Master Responses
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Request Command Group (used for Master implementation)

MDB Generic Master sends request to the Bus using "R" command set. These commands have the following structure.

MDB Master Request
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The xx and yyyy data has to be checked directly on the MDB protocol here

Possible answers from the interface:

These answers are actually sent by the slave (either simulated with the MDB interface or sent by an actual peripheral like a coin acceptor or a cashless device).

MDB Slave Responses
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R,14,01 - send "reader enable" command to cashless device on address 0x10

- note that the arguments are given in hexadecimal, 2 digits

Reset Bus
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