Hello, I want to read multiple registers from modbus that are not in a sequence, what would be the best way? Is there any modbus node that I can use to do it, or shoud I use two modbus flex read and then join. I was trying the last solution without any luck joining the data array to after process i…

Hello .. [image] ELParreira: I want to read multiple registers from modbus that are not in a sequence I think with the latest version of Modbus nodes v.5.14.1 there is a new node called Modbus-Flex-Sequencer that supposedly does just that .. do sequential reads .. but i havent tested it yet…

It might be better to wire the modbus nodes in series. So after the first one save the data to a message property and then wire to the function node and second modbus node, then you will have a message with both results in it. The modbus node should not destroy the saved property. Then you won't …

[image] UnborN: I think with the latest version of Modbus nodes v.5.14.1 there is a new node called Modbus-Flex-Sequencer that supposedly does just that .. do sequential reads .. but i havent tested it yet. Whats wrong with the setup you have now ? .. what problem do you have joining the mes …

Sorry Colin, I didn't understood your suggestion. I'm new to Node Red. But enjoying it more everyday. Cheers

I haven't got the modbus nodes installed so can only mock up an image to show the flow. [image]

[image] ELParreira: I'll give sequencer a try and then let you know. I did a quick test with the Modbus-Flex-Sequencer and it doesnt work :wink: (i think its still under development) Even if it did work, it would be a headache to route its results to individual buffer parsers to convert your…

Also arrived to the same conclusion.

I parse a CSV with the registers i want to read, and their context, then loop each of the points into the flex getter node for a read and store all the register values into flow or global vars.

[image] PLCMercenary: then loop each of the points into the flex getter node This sounds like a good approach. I wanted to ask whether you do a small delay when sending the messages this way or do you let the Flex getter node queue and delay the msgs with its settings.

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Read Registers From Modbus Not in Sequence

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Steve-Mcl 30 September 2021 14:48 6

@Colin is talking about wiring all nodes in series, like this: Modbus Serial - Whole bus disconnects when one device drops - #16 by Steve-Mcl

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Read Registers From Modbus Not in Sequence

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