How to pick a msg from a msg stream

General
1

Hi there!
I got the following scenario:

  • sensor A is delivering continuously data by means of serial interface
  • sensor B is delivering one trigger msg every once in a while (operator hits a button)

What I am trying to achieve is the following:
At the moment the sensor B msg is received the next msg (or previous is ok too) of sensor A shall be picked. The data of both msg needs to be merged. The merged data of msgA and msgB are then handled in following nodes.

How can I do something like that in node-red?
Thanks a lot!
JR

2

One way is with the contrib node node-red-contrib-queue-gate. Sensor B will trigger the release from the queue of the last message from Sensor A.

Untitled 1

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1 Like
3

Wow, thank you so much! That works for me.
Cheers
JR

4

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