Sutron Corporation X-Link Operations & Maintenance Manual, Rev 1.63 5/24/2016 pg. 50
5.2.
Retransmissions
Starting with version 1.57, X-Link is able to make retransmissions (ReTx).
Retransmissions are retries of failed scheduled transmissions.
When a scheduled transmission fails, X-Link notes the time of the failure. Once a
future scheduled transmission succeeds, X-Link will proceed to re-transmit the
data from the missing transmissions.
Here is an example of retransmissions in action:
o
12:00 Scheduled transmission succeeds. All is well.
o
12:30 Scheduled transmission fails due to lack of network.
o
13:00 Another scheduled transmission fails.
o
13:30 Scheduled transmission succeeds. Network is back up.
o
13:31 Retransmission with data as if it were 12:30 completes.
o
13:32 Retransmission with data as if it were 13:00 completes. All
previously missing data has been transmitted.
o
14: 00 Scheduled transmission completes. Back to business as usual.
For retransmissions to take place, the setting
Retransmit
must be enabled. It is
enabled by default. A proper
Tx Format
is also needed to ensure that the data in
the transmission is timestamped. Pseudobinary B is the only unacceptable
format. Use Pseudobinary D instead of Pseudobinary B.
Enable
Retransmit
and choose any
Tx Format
but Pseudobinary B to take
advantage of Retransmissions.
o
Toggling recording, clearing status, and changing telemetry settings will
reset retransmissions. Rebooting a station will NOT reset transmissions.
o
If X-Link does not have any data logged for the relevant time period, no
retransmission will be made.
o
Loss of power cannot be overcome with retransmissions.
o
Retransmissions are only useful if X-Link is still able to collect and log
sensor data.
o
Data older than 7 days will not be retransmitted.
o
If there are pending retransmissions, Telemetry status will show when
the first failure happened. E.g. "Retransmissions pending from
2014/11/19 12:30:00"
