Basic questions about Cayenne with esp8266

[1miltfriedman]

I am using Cayenne to collect analog data from a esp8266 dev board (NodeMCU) programmed in Arduino IDE. I have tested the Cayenne ESP8266 example and get a good connection with the time data received. Here are my questions:

1. I can’t find documentation on the Cayenne Write functions so I’m not sure whats possible.
2. I don’t know what the best way is to collect data from multiple devices (around my yard).
3. I don’t know the best practice for saving battery power with the dev board.

Any help/info on these topics is appreciated. Any questions are welcome.

[shramik_salgaonkar]

@1miltfriedman

I can’t find documentation on the Cayenne Write functions so I’m not sure whats possible.

Data types for Cayenne MQTT API

In light of some questions about how to pass data to Cayenne via MQTT, and knowing that the table in our documentation is incorrect/showing not-yet-released items, I wanted to share the following table to help with building virtualWrite() statements to pass data to Cayenne. virtualWrite() expects a parameter format like: virtualWrite(mqtt_channel_number, value, "type value", "unit value") You may have noticed that we have shorter functions like luxWrite() that only need two parameters becau…

@1miltfriedman

I don’t know what the best way is to collect data from multiple devices (around my yard).

create a separate project on the cayenne dashboard by click on “+”. add the widgets from all the different devices to this dashboard.

@1miltfriedman

I don’t know the best practice for saving battery power with the dev board.

you can try this Battery Powered ESP8266 Temperature/Humidity Monitor with DHT11

[1miltfriedman]

Perfect. Thanks.

[adam]

With the full dev module it’s hard to save a lot of power, but putting it to sleep is definitely going to help. If you get a bare ESP module you can use a super low drop out voltage regulator and really squeeze the most out of your batteries. The AMS1117 (on the dev board) has a dropout of about 1v where a HT7333 is about 90mV and that extra 1v from the battery can make a huge life span difference. With this example if you have a lipo battery with a dev board your dev board will stop powering up at around 4v where a HT7333 will work all the way down to around 3v.

[1miltfriedman]

What is the best practice now for sleeping if no wifi connection is made? Is there a way for Cayenne to send a notification when device is silent for more than 30 min?

BTW, I have connected a 3.5 x 6.5 cm solar panel to my lipo battery charger and get full charging during the day (1000 mAh lipo), so battery power is not the issue so much as notification of poor wifi.

[adam]

There is nothing yet available on the Cayenne side that I’m aware of. @shramik_salgaonkar any ideas?

[shramik_salgaonkar]

let me check with the team.