Hi all, Hoping someone can help as this is doing my head in! I have data coming in from a serial port (wireless USB dongle) which is connected fine and happily throwing out data whenever it arrives. The data arrives in this format: {SN:0451D4,TN1:22.40,TM1:22.40,TA1:22.40,TN2:-27.04,TM2:-27.04,T…

Have you read the page in the docs about working with messages? Try starting with that and a debug node with ( and without) a jasn node

That data looks almost JSON. Have you tried sending the data to JSON node to see if it will convert. And check out the help info about "working with messages". It will help you tremendously. It's about a 10min read. Definitely worth it.

Thanks for the advice. I haven’t tried the JSON node yet. Tbh I’m a bit baffled by the whole thing! I did try to read the beginners guide but again i just got lost.

[image] NPLPRS: The data arrives in this format: {SN:0451D4,TN1:22.40,TM1:22.40,TA1:22.40,TN2:-27.04,TM2:-27.04,TA2:-27.04} Which values do you want to extract? If you strip off the "{" and "} you have a well ordered set of data separated by "," and each pair is further separated by ":" - Ju…

sadly it's close but not JSON so the JSON node won't help... if the sensor would send {"SN":"0451D4","TN1":22.40, ... i.e. with quotes around any text, then you would be fine. However you should be able to create an object like this flow below - you can then use a switch node to pick off the par…

Thanks for the help. I just want the TN1: number really, the rest i dont need. Just cant work out how to do it!.

[image] NPLPRS: {SN:0451D4,TN1:22.40,TM1:22.40,TA1:22.40,TN2:-27.04,TM2:-27.04,TA2:-27.04} Feed this into a split node and split it on a comma. Next feed the output into a switch node and select 'contains' and set the value to TN1 - that will only pass the TN1 string. Feed this to another spl…

[image] NPLPRS: {SN:0451D4,TN1:22.40,TM1:22.40,TA1:22.40,TN2:-27.04,TM2:-27.04,TA2:-27.04} I see you already have a solution -- but there are always other ways to do it! Whenever I see a well-ordered string like this (that is not quite parsable as JSON), I think of using a regex parser... In…

Node-RED

Node-RED Forum

Extracting Data from payload

General

NPLPRS 17 September 2019 16:16 10

OMG thank you so much - worked perfectly.

Topic		Replies	Views
Get string from serial port and convert to separate key General	6	689	9 March 2022
How do I extract values from a JSON string? General function-node	15	4944	19 July 2022
Extract numbers from serial input General	7	158	10 January 2025
Filter Payload Data for Dashboard General	4	1939	20 June 2018
Split string coming from API General	3	399	3 May 2019

Copyright OpenJS Foundation and Node-RED contributors. All rights reserved. The OpenJS Foundation has registered trademarks and uses trademarks. For a list of trademarks of the OpenJS Foundation, please see our Trademark Policy and Trademark List. Trademarks and logos not indicated on the list of OpenJS Foundation trademarks are trademarks™ or registered® trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.

Extracting Data from payload

Related topics