Lin Communication Flow - Fujitsu F2MC-8FX Series User Manual

AN07-00200-03E
5.3

LIN communication flow

In general LIN communication, one master communicates with numerous slaves. LINs, which adopt
a bus topology, connect the master and all the slaves using a single wire, so header electrical signals
sent by the master are transmitted by the wire to all the slaves. The slaves check the frame ID, and if
the header is addressed to them, sent a response to the master according to the content received. If
the header received is addressed to another slave, it is ignored. In this way, 1-to-1 communication
between the master and each slave is achieved.
This section explains the actual trading of communications. Currently, functions are allocated to
each of the slaves from 1 to 15.The master first communicates with slave 1 and turns the motor ((1)
in Figure 5-5 Main LIN network configuration and Figure 5-6 Example of communication sequence
between the master and slaves during normal communication), and next acquires sensor information
by communicating with slave 3. ((2) in "Figure 5-5 Main LIN network configuration" and Figure 5-6
Example of communication sequence between the master and slaves during normal communication.)
Thereafter, the motor is turned by communications with slave 2 ((3) in Figure 5-5 Main LIN network
configuration and Figure 5 6 Communications sequence between master and slave during normal
communications).The master acquires sensor information from slave 3 again ((4) in Figure 5-5 Main
LIN network configuration and Figure 5 6 Communications sequence between master and slave
during normal communications), and finally turns ON the lamp by communicating with slave 15 ((5)
in Figure 5-5 Main LIN network configuration and Figure 5 6 Communications sequence between
master and slave during normal communications).In this chain of communications, communications
between the master and slaves 2 and 3 are contiguous, and the master processes the motor turning by
communicating with slave 2 using sensor information acquired by communicating with slave 3 first.
In this way, during actual communications the master and multiple slaves repeatedly communicate
on a 1-to-1 basis.
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