There are four startup scenarios that requires synchronization between the Host and Module:
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Upon startup, the Host must issue the /wiki/spaces/SPRHA17/pages/37093548Host Startup Ready command. On receiving the /wiki/spaces/SPRHA17/pages/37093548Startup Sync Request command will be sent from the Module to the Host(see figure 1 for an alternate sequence). The Host may then enter the Startup Synchronization sequence to perform the aforementioned configuration of the endpoints, clusters and attributes. The Startup Sync Request command from the Module will include information on which application configurations may be restored from external flash and which the Host must reconfigure.
The Host completes the phase by sending the /wiki/spaces/SPRHA17/pages/37093548Startup Sync Complete command to the Module.
This page provides illustrated examples of the Startup Synchronization sequence.
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Startup Synchronization Request Retries
Figure (2) illustrates the sequence when the Module initializes before the Host (described in scenario (2)). In this scenario the Module starts sending Startup Sync Request periodically(every 5 seconds) to ensure that the Host receives the message even if the Host starts up slower than the Module. You can see in the figure, the Host Startup Ready command is sent after the Startup Sync Request. The Module is required to send a final Startup Sync Request after receiving the Host Startup Ready command. The Host can now start the Configuration sequence.
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