Heya! So I have 6 modbus sensors that are polled each, 1 sec apart. They run into a join node that outputs an array after 6 consecutive messages, and this is written to a CSV file. I have added a function node to each before the array just to track their location (the sensors are measuring zero on …

Use the join node in key/value pair mode (making sure you have different topics for each value). Then you will get all the values in an object individually identified. If you then want them in an array you can build the array in the right order.

Awesome! Thanks for that. Took me a bit but I got there in the end

I am experiencing a similar problem relating to the order of items using the "Join" node. I have tried the suggestion to use key/value pair mode, but get an error "message missing key property 'msg.topic' - cannot add to object" I am reading two values from a Modbus device. I have named each "Topi…

[image] RickW: Could these be loosing the "Topic"? Add a debug node after the node in question and set it to display complete message object.

Thank you, Debug complete message doesn't show "Topic" so it looks like I will need to use a Function Node to get a Topic into the flow. I will do some experimenting. This is taking me from the easy level of Node-Red to what to me seems difficult. Lets see how I go.

Take a look at what i ended up doing and it works. May be of some help [{"id":"2d907ade.e3dbd6","type":"subflow","name":"BLINK OFF","info":"","category":"","in":[{"x":60,"y":80,"wires":[{"id":"bff8199f.aa7d08"}]}],"out":[]},{"id":"877299f.1e3ce68","type":"mraa-gpio-dout","z":"2d907ade.e3dbd6","name…

You already have a set of change nodes in each leg of the flow - just add another rule to them [image]

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Join node and order of messages

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ukmoose 2 September 2019 06:12 5

Add a debug node after the node in question and set it to display complete message object.

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Join node and order of messages

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