Zennio ZCL-MCC, Руководство пользователя

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MCC
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2.5 INITIAL STATES
When MCC has just been programmed, it always starts under the
“undefined state”. At
that point, the selection algorithm (see section 2.3) begins, the result of which will
determine whether the device switches to master or to slave.
Note : as stated in section 2.3
, MCC may return to the “undefined” if a master
notification is received from the bus immediately after having sent an analogous
notification. To prevent collisions between two MCCs opting to behave as masters, the
“undefined” state will be adopted and the role selection algorithm will start
.
Should a bus power failure take place before the selection algorithm has concluded,
MCC will retry the role selection once it recovers from the power failure.
On the other hand, if a bus failure takes place once MCC had a role already assigned:
If it was working as a slave, it will reboot as such and operate normally.
If it was working as a master, it will reboot as such but will first ensure that no
other master notifications are received during 1.5 times the master notification
period.
The following table and graphs sum up all the above:
Initial Mode Event Next Mode Actions to perform
Undefined
Download
Undefined Beginning of the selection algorithm.
Reboot
Slave
Download
Reboot Slave Slave notification and normal operation.
Master
Download Undefined Beginning of the selection algorithm.
Reboot Master
Wait for 1.5x the master notification time.
- Master notifications received

switch to
slave (and notify it 1 ).
- No master notification received

remain
as master (and notify it).
Table 2 Initial states after ETS download or reboot (power failure).
1
READ requests will also be transmitted, if configured.