Laird Sentrius RS191, Руководство по настройке

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US
– RS191
Table 10 - US retransmissions per data rate
Uplink Data Rate
Total Number of
Retransmissions
DR4 8
DR3 8
DR2 6
DR1 4
DR0 2
EU
– RS186
Table 11 - EU retransmissions per data rate
Uplink Data Rate
Total Number of
Retransmissions
DR7 8
DR6 8
DR5 8
DR4 8
DR3 8
DR2 6
DR1 4
DR0 2
For example, if in the US and at DR4, the maximum number of transmissions before a message is considered to have failed is
eight. This means it transmits twice at DR4, twice at DR3, twice at DR2, and twice at DR1. If all transmissions are
unsuccessful, the next time the device transmits, it is at DR0. If any of the data rates before that are successful, the unit
remains at that data rate until the server deems its link is good enough to step up the data rate via ADR.
If the sensor detects three consecutive confirmed RF messages are lost, the sensor assumes the connection to the server is
lost and stops sending data. It reverts to the join sequence described in the
Join Sequence section of this guide.
If configured for the Laird or Laird 2 Packet Formats, after the sensor joins a network, it can start sending data packets to the
server. However, before the sensor can use the backlog feature it must first get the network time. This is sent in epoch time,
number of seconds since January 1, 2015. Once the network time is received, the device can be configured to store
unacknowledged packets in the Flash device.
On the successful reception of a Join Request, the server may automatically transmit the network time message to the sensor
as part of the first downlink message. If the network server does not provide a Laird format time message, the sensor requests
it. This is achieved by setting bit 0 of the options byte of a data uplink message to 1. More information on this can be seen in
the RS1xx LoRa Protocol document available from the RS1xx product page.
I
MPORTANT
!!
When configured for the Laird and Laird 2 packet formats, the Sentrius ™ Sensor is intended to work
with a LoRa network server that provides network time in the custom Laird Format. See the RS1xx
LoRa Protocol document which can be found at the link located in the Additional information section.
This is required for the sensor to store data in the internal log flash. The sensor transmits data without
the network time being available, but it cannot commit this to flash storage. This does not apply when
configured for the Cayenne packet format, due to the protocol not supporting a timestamp.