Send dummy measurement

Dummy temperature in Cayenne

Dummy temperature parameters

Fix widget to dashboard

Dummy temperature history

Cayenne keeps measurement values which can be plotted as a history plot

or downloaded for further evaluation

A custom widget

A gauge widget

Dummy temperature gauge on the dashboard

Gauge value ranges

It's hot!

Several dummy measurements

Now we want to send a dummy temperature and a dummy humidity value.

How do we distinguish?

They use different communication channels!

Sending temperature and humidity: the code

Dashboard with temperature and humidity

Other measurements

We have seen that we can send temperature with

• client.celsiusWrite(channel,temp)

• Client.humidityWrite(channel,hum)

Measurements implemented in the Cayenne Client

How to control a device?

Cayenne supplies only 2 control widgets:

• a push button
• A slider

Cayenne Slider

We can define the range for the slider in the above case: 0..255

Slider on the dashboard

A Cayenne Button

Dashboard with button

How to receive commands

We must define a callback function, which is called

whenever the user of the Cayenne dashboard

changes a setting on the push button or slider

The callback takes a message parameter which is a tuple of

• Cayenne topic
• Cayenne payload

Cayenne command message

Please compare the command message with our credentials and try to find out

to which channel this command has been addressed. Can you find the values as well?

Remember: we defined the push button on channel 3 and the slider in channel 2!

Exercises!

More on how to interpret this message in the next session