A Simple MQTT Pub/Sub Node With Arduino UNO and W5100 Ethernetshield

Nowadays many MQTT nodes are based around the ESP8266. However far before the ESP8266 the Arduino UNO already had Ethernet capabilities with an Ethernetshield. The aim of this instructable is to show how one can use A UNO with W5100 shield or module as an MQTT node and in the software I will show some simple techniques of how to deal with outbound MQTT messages and inbound MQTT messages. If you still have an Old ENC28J60 Ethershield, don't despair, one can use those as well. I will cover that in my next instructable.
ORIGINAL POST
By diy_bloke
components
Hardware Components
Software Apps and online services
MQTT
details

MQTT.jpg

An MQTT broker can be housed on your own LAN and often a RaspberryPi is used for that, or a public broker can be used.

Now obviously, just building one Node is not going to do much good. Who is it going to talk to? So obviously this would fit in a bigger systems with various nodes talking to eachother and the user having a frienly interface such as OpenHab. But in the google playstore various MQTTdashboards are available as app that allow for a simple interface. When developing MQTT software, it is always smart to install mqtt-spy. It is available for several platforms and what it basically does is to show MQTT messages going around on your LAN and to allow you to manually send MQTT messages

MQTT.jpg

An MQTT broker can be housed on your own LAN and often a RaspberryPi is used for that, or a public broker can be used.

Now obviously, just building one Node is not going to do much good. Who is it going to talk to? So obviously this would fit in a bigger systems with various nodes talking to eachother and the user having a frienly interface such as OpenHab. But in the google playstore various MQTTdashboards are available as app that allow for a simple interface. When developing MQTT software, it is always smart to install mqtt-spy. It is available for several platforms and what it basically does is to show MQTT messages going around on your LAN and to allow you to manually send MQTT messages

documents
Code
W5100MQTT_v2
https://drive.google.com/file/d/0B6c8mGbetkOULVI4UGhHMFZDN0E/view

1
COMMENTS

Please Login to comment
1 Comment authors
gopFool Recent comment authors
  Subscribe  
newest oldest most voted
Notify of
gopFool
Member

Code does not compile.
Errors: multiple definition of `PubSubClient::PubSubClient()’
What version of PubSubClient is used, and where is this located (source indicates local)