User's Guide

Industrial Tracker User Guide FW 1.6 V1.1
Page 8 of 13
11 July 2018
Restricted distribution
Notes
1. Any unexpected message (unknown message type, bad length, ...) is discarded. However, the ack
token is updated even if the message is discarded (if the payload is at least 2 bytes long).
2. The LoRa port to be used for downlink is 2.
7.1 Ack Token
It provides a way to indicate to the application that a given message has been received and processed by the
tracker.
The ack token is transmitted in every uplink message, and it is updated when the tracker receives a LoRa
message. This way, each time the server receives a LoRa uplink, it knows whether the previous message has
been received.
The ack token is four bits size. Its value ranges from 0 to 15(0x0F).
Notes
1. The ack token value must be updated for each downlink to be used by the application.
2. It’s up to the application to process or not the ack tokens.
3. It’s up to the application to manage the confirmations. It can either wait for the matching ack token
in the uplink message before sending another downlink or send multiple downlink and later waits for
the acks.
7.2 Mode Configuration
The operating mode can be remotely configured with a downlink LoRa message built as follow:
Byte 0
Byte 1
Byte 2
0x02
ACK
Mode
ACK: Ack token. Refer to the associated section.
Mode: operating modes. Acceptable values are:
➢ 0- Standby
➢ 1- Motion tracking
➢ 2- Permanent tracking
➢ 3- Motion start/end tracking
➢ 4- Activity tracking
Example:
Changing the operating mode to “motion track” (01) with an ack token of 3: 0x020301.
7.3 Position on demand
Whatever the state, a position can be requested from the tracker by the message:
Byte 0
Byte 1
0x01
ACK
Example:
Position on demand message with ack token of 2: 0x0102.