unstable reading tags - Githubissues

st-one-io / node-red-contrib-cip-ethernet-ip

A Node-RED node to interact with Allen Bradley / Rockwell PLCs

GNU General Public License v3.0

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unstable reading tags #4

Closed tokke100 closed 5 years ago

tokke100 commented 5 years ago

I have setup the node to read a list of tags every second. It sometimes returns every 3 seconds, sometimes 3-4 times in the same second.

gfcittolin commented 5 years ago

Internally, the library performs the following activities in a loop:

perform a read of the tag group
perform a write of the tag group
waits the specified amount of time

So I'd expect that it could take a bit more time than the configured amount, mainly if there are a lot of tags, but not being faster than that. Also, please note that Node.JS (and therefore also Node-RED) is single-threaded, so if your flow is performing other blocking activities, it could affect the readings.

gfcittolin commented 5 years ago

Closing due to the lack of activity in the thread. Please feel free to reopen it if needed