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DigiMesh 2.4 User Manual
DigiMesh Synchronization Messages
A sleep coordinator will regularly send sync messages to keep the network in sync. Nodes which
have not been synchronized or, in some cases, which have lost sync will also send messages
requesting sync information.
Deployment mode is used by sleep compatible nodes when they are first powered up and the
sync message has not been relayed. A sleep coordinator in deployment mode will rapidly send
sync messages until it receives a relay of one of those messages. This allows a network to be
deployed more effectively and allows a sleep coordinator which is accidentally or intentionally
reset to rapidly re-synchronize with the rest of the network. If a node which has exited
deployment mode receives a sync message from a sleep coordinator which is in deployment
mode, the sync will be rejected and a corrective sync will be sent to the sleep coordinator.
Deployment mode can be disabled using the sleep options command (SO).
A sleep coordinator which is not in deployment mode or which has had deployment mode
disabled will send a sync message at the beginning of the wake cycle. The sleep coordinator will
then listen for a neighboring node to relay the sync. If the relay is not heard, the sync
coordinator will send the sync one additional time.
A node which is not acting as a sleep coordinator which has never been synchronized will send a
message requesting sync information at the beginning of its wake cycle. Synchronized nodes
which receive one of these messages will respond with a synchronization packet. Nodes which
are configured as non-sleep coordinators (using the SO command) which have gone six or more
cycles without hearing a sync will also send a message requesting sync at the beginning of their
wake period.
The following diagram illustrates the synchronization behavior of sleep compatible modules:
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