This should be a simple application but we are struggling. The least significant bit is to the right. Bit 1 = Input 1 Register read = 1 Bit 2 = Input 2 Register read = 2 Bit 3 = Input 3 Register read = 4 Bit 4 = Input 4 Register read = 8 Can make this work with = command when only one input is…

Colin: Many thanks. Found a 16 bit split function that does what we need in a simple way. [image] Works very well

[image] HansZnarf: [image] If that is what you want then you can use const b0 = (msg.payload & 1) const b1 = (msg.payload & 2) >> 1 const b2 = (msg.payload & 4) >> 2 const b3 = (msg.payload & 8) >> 3 msg.payload = {b0: b0, b1: b1, b2: b2, b3: b3} return msg

Thanks: That code returns this [image] Still do not know how to pull these out as individual item for bool logic and dashboard. More used to how PLCs each have a bool rung that can be used. How to we split these into four useable objects?

What exactly do you want to do with it? What I have provided does have the four values available to do what you want with them. Unless you tell us exactly what that is then it is impossible to help.

Colin, I think the bit-unloader node already creates that object. And the ask is how to take those bits and feed into a series of leds on a dashboard. But which leds ? [image] HansZnarf: Would like a bool 1 as an output so each input can be presented in a dashboard as in: Input 1 to dashboard…

The surprise with bit 31 in JavaScript :blush:

[image] dceejay: I think the bit-unloader node already creates that object Ah yes, looking back I see you are right. @HansZnarf as Dave pointed out earlier, you can use a Change node to extract an individual value from the object. So a Change node configured like this would extract b1 as 1 …

[image] iiot2k: surprise with bit 31 in JavaScript Good point. In fact my code would be better using the unsigned shift operator const b0 = (msg.payload & 1) const b1 = (msg.payload & 2) >>> 1 const b2 = (msg.payload & 4) >>> 2 const b3 = (msg.payload & 8) >>> 3 msg.payload = {b0: b0, b1: …

JavaScript converts on all bit operation the value first to a 32bit signed integer. Bit 31 is then the sign. This is the surprise on bit operation with bit 31.

Yes, but I am not sure of the relevance of that here. Do you mean that the modified code I posted will not work?

Or you could use buffer-parser [image] Understanding and parsing 16-bit words via Modbus General There is no need to use buffer maker as the data from the flex getter contains a buffer (use a debug node set to show complete message) Also, you can make a better output usi…

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Steve-Mcl 2 September 2022 09:04 18

Or you could use buffer-parser

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Bit Strip from Int

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