Chapter 2: Setup and Operation
2-9
Stride MQTT Gateway User Manual, 1st Edition
• If the variable read is to be published to your MQTT broker:
– Enter an MQTT
Topic (PUB)
. The circle arrow icon to the right of the Topic name will
reset the name to the default <DEVICE_NAME>/get/<VARIABLE_NAME>, where
<DEVICE_NAME> and <VARIABLE_NAME> will automatically populate from the values
defined for the device.
– Select whether the topic should be published
On value change
or
At a fixed frequency
, and
enter the
Threshold
amount of change to trigger a publish event or the time interval (
Every (s)
)
at which to publish, respectively.
– Enter the Quality of Service level (
QoS
).
MQTT Quality of Service Levels
QoS
Description
0
Does not include confirmation of receipt
1
Guarantees the delivery of the message at least once to a receiver
2
Guarantees the delivery of the message once and only once to a receiver
– If
Retain
is checked, the MQTT broker will hold the most recently published message in this
topic to sent in reply to future client Subscribe requests.
• If the variable is to be written based on a subscribed MQTT topic:
– Enter an MQTT
Topic (SUB)
. The circle arrow icon to the right of the Topic name will
reset the name to the default <DEVICE_NAME>/set/<VARIABLE_NAME>, where
<DEVICE_NAME> and <VARIABLE_NAME> will automatically populate from the values
defined for the device.
– Enter the Quality of Service level (
QoS
), as defined for the publish case above.
• Click
SAVE
when finished defining all variables and MQTT topics.
After a device has been added to the channel, the simulated LED to the right of the device on the DEVICES
tab and the channel name on the CHANNELS tab will turn green if communication is successful and
red while the channel is in an error state. The clipboard icon on each channel will open a real-time log of
communications on that channel.
