M-Bus

M-Bus = Meter-Bus

The M-Bus is a fieldbus for the recording consumption data (e.g. energy meters). Further details about M-Bus can be found under www.m-bus.com. The M-Bus is European standard and is described in the EN1434 standard. The data are sent serially from a slave (measuring device) to a master (M-Bus master terminal KL6781). Master and slave are connected via a two-wire cable that is protected against polarity reversal. Up to 40 slaves can be connected to a KL6781 with any topology (star or line). Devices from different manufacturers can be operated on the same bus.

The M-Bus master (KL6781) controls the communication on the bus by requesting data from the slaves. The slaves can respond with a fixed or variable data structure. The M-Bus library only evaluates data with variable data structure (low byte first). The slaves do not communicate with each other. The data have to be requested sequentially from the slaves.