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Here the minimum number of new events is 2, so if after the last message there were none or only 1 event there will be no new counter update message ever.
There is also another factor that impacts when the counter update message is sent. Cars are counted when they leave the sensor, and even after that, there is an additional delay of 5 seconds to allow the passing car to go farther and check if there is another car following it. It allows avoiding sending messages in unstable conditions or under a car. There is a timeout of 30 seconds for this mechanism too, so if a message was ready to be sent, but conditions were not good for 30 seconds it will be sent anyway(even under a car).
The counter update message can be configured as not confirmed with or without repetitions. It reduces the usage of the duty cycle to acknowledge all messages, but may also reduce the percentage of successfully received messages by the Gateway.
The DataRate is used in the uplink messages by the sensor is DR2 by default but may be configured from DR0 to DR5, ADR(Adaptive Data Rate also can be enabled).
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