UM1573

Network model description

Doc ID 023619 Rev 1

5/27

The data exchange between all the nodes connected to the same power line also uses a

data frame acknowledgement mechanism. In this way, the master knows if its own

transmitted data packet has been correctly delivered to the target node since it receives an

acknowledgment frame for each data frame sent to a target device. This acknowledgement

excludes some data frames sent in broadcast by the master.

Figure 2.

Data exchange diagram

The repetition feature improves the probability that the data frame is delivered to nodes that

are far away or under noisy network environments. As all the other nodes are connected in

the same power line, they continuously sense the network catching all data transiting on it.

Depending on the device addressing and the data frame/acknowledge flow, each node is

able to detect if the sensed frame must be repeated, discharged, or processed. A data

identification technique (frame ID) and the forward error correction redundancy (FEC) in the

data frames are implemented in order to avoid cyclic repetitions or data loss that can cause

an unnecessary increase of data traffic.

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