# Single Bit's to Integer

**URL:** <https://discourse.nodered.org/t/single-bits-to-integer/83382>\
**Category:** General\
**Created:** [2 December 2023 16:11 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382 "2023-12-02T16:11:53Z")\
**Posts on this page:** 9\
**Page:** 1

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**Author:** ![good\_mike](https://avatars.discourse-cdn.com/v4/letter/g/71e660/32.png) [@good\_mike](https://discourse.nodered.org/u/good_mike)\
**Post date:** [2 December 2023 16:11 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/1 "2023-12-02T16:11:53Z")

</div>

Hello,  
unfortunately I have little experience with Node Red and json in particular.

The following problem:  
I generate several bits in Nodered and then want to pass them to a PLC in an 16bit integer word via ADS.

So I need a function with 16 individual bits on the input side and a 16bit int. value as output.

thx in advance for your help!!

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<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [2 December 2023 16:16 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/2 "2023-12-02T16:16:43Z")

</div>

> [@good\_mike](#):
>
> I generate several bits in Nodered

How do you generate them - show us.

> [@good\_mike](#):
>
> So I need a function with 16 individual bits on the input side

Node-RED nodes will only ever have 1 input. This is by design. There are various methods for "tagging" the input data to differentiate "things". For example, a topic of "bit0" and payload of `true` can be easily differentiated from a topic of "bit1", payload `true`

Like wise, the payload can be an object e.g.

```auto
{
  bit0: true,
  bit1: true,
  bit2: false
}

```

or an array `[true, true, false]`

or an array of numbers `[1,1,0]`

and so on.

* * *

to help you further, first explain what you have (and show us).

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<div class="post-metadata">

**Author:** ![good\_mike](https://avatars.discourse-cdn.com/v4/letter/g/71e660/32.png) [@good\_mike](https://discourse.nodered.org/u/good_mike)\
**Post date:** [2 December 2023 16:43 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/3 "2023-12-02T16:43:58Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/9/4932463d9ea64bdcf619c861660aa415f4c79df5.png)

I get single bits (true/false) via Google and want to send them combined via an integer value to a Beckhoff PLC. There I can decode the integer value into the individual bits.

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<div class="post-metadata">

**Author:** ![good\_mike](https://avatars.discourse-cdn.com/v4/letter/g/71e660/32.png) [@good\_mike](https://discourse.nodered.org/u/good_mike)\
**Post date:** [2 December 2023 16:46 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/4 "2023-12-02T16:46:17Z")

</div>

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/b/7bc3df1e5f6e689b1143c2c9321663fa25041ad0.png)  
something like that only in reverse

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<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [2 December 2023 16:54 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/5 "2023-12-02T16:54:38Z")

</div>

A basic and absolute truth in node red, it that messages NEVER arrive at the same input of a node at the same time.

The fact you have (in this screenshot) 2 sources of data and want to combine these means you should be looking at the join node to "join" the values into one message, then, once all data is in 1 message, you can begin to work out how to convert the values into a single integer.

This cookbook example explains the join node: [Create a single message from separate streams of messages : Node-RED](https://cookbook.nodered.org/basic/join-streams)

If you want further help, copy a few REAL data examples (using the "Copy Value" button that appears under your mouse when you hover over a debug message in the side bar) and paste them in a reply as text (not screenshots)

---

<div class="post-metadata">

**Author:** ![good\_mike](https://avatars.discourse-cdn.com/v4/letter/g/71e660/32.png) [@good\_mike](https://discourse.nodered.org/u/good_mike)\
**Post date:** [2 December 2023 17:13 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/6 "2023-12-02T17:13:19Z")

</div>

```auto
[{"id":"7a7ab50bfdbb36b9","type":"join","z":"f0827cc6.fe0a7","name":"","mode":"custom","build":"object","property":"payload","propertyType":"msg","key":"topic","joiner":"\\n","joinerType":"str","accumulate":true,"timeout":"","count":"","reduceRight":false,"reduceExp":"","reduceInit":"","reduceInitType":"","reduceFixup":"","x":1170,"y":260,"wires":[["8fedfbdf19d8dd4a"]]},{"id":"a854d24607b174fc","type":"inject","z":"f0827cc6.fe0a7","name":"Bit_0_True","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_0","payload":"true","payloadType":"bool","x":960,"y":180,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"c19636ac99c0dff4","type":"inject","z":"f0827cc6.fe0a7","name":"Bit_0_False","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_1","payload":"false","payloadType":"bool","x":970,"y":220,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"0b8e3816c26b29c3","type":"inject","z":"f0827cc6.fe0a7","name":"Bit_1_True","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_1","payload":"true","payloadType":"bool","x":960,"y":300,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"3701308d0b13e071","type":"inject","z":"f0827cc6.fe0a7","name":"Bit_1_False","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_1","payload":"false","payloadType":"bool","x":970,"y":340,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"8fedfbdf19d8dd4a","type":"debug","z":"f0827cc6.fe0a7","name":"Int_Value","active":true,"tosidebar":true,"console":false,"tostatus":true,"complete":"payload","targetType":"msg","statusVal":"payload","statusType":"auto","x":1400,"y":260,"wires":[]}]

```

If Bit 0 is true \> Int Value should 1  
If Bit 1 is true \> Int Value should 3  
.....

---

<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [3 December 2023 10:30 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/7 "2023-12-03T10:30:44Z")

</div>

Here is one way:

![chrome_FEMSjUAG5m](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/9/4942457e481607179d6de3ae81fb1f28b95b1b2d.gif)

```auto
[{"id":"7a7ab50bfdbb36b9","type":"join","z":"a12c69dd3cb81690","name":"","mode":"custom","build":"object","property":"payload","propertyType":"msg","key":"topic","joiner":"\\n","joinerType":"str","accumulate":true,"timeout":"","count":"2","reduceRight":false,"reduceExp":"","reduceInit":"","reduceInitType":"","reduceFixup":"","x":1890,"y":460,"wires":[["8fedfbdf19d8dd4a","8dc03c2edc7f3610"]]},{"id":"a854d24607b174fc","type":"inject","z":"a12c69dd3cb81690","name":"Bit_0_True","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_0","payload":"true","payloadType":"bool","x":1680,"y":380,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"c19636ac99c0dff4","type":"inject","z":"a12c69dd3cb81690","name":"Bit_0_False","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_0","payload":"false","payloadType":"bool","x":1690,"y":420,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"0b8e3816c26b29c3","type":"inject","z":"a12c69dd3cb81690","name":"Bit_1_True","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_1","payload":"true","payloadType":"bool","x":1680,"y":500,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"3701308d0b13e071","type":"inject","z":"a12c69dd3cb81690","name":"Bit_1_False","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"Bit_1","payload":"false","payloadType":"bool","x":1690,"y":540,"wires":[["7a7ab50bfdbb36b9"]]},{"id":"8fedfbdf19d8dd4a","type":"debug","z":"a12c69dd3cb81690","name":"Int_Value","active":false,"tosidebar":true,"console":false,"tostatus":true,"complete":"payload","targetType":"msg","statusVal":"payload","statusType":"auto","x":2080,"y":460,"wires":[]},{"id":"01d225c3b918a471","type":"debug","z":"a12c69dd3cb81690","name":"debug 239","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":2110,"y":560,"wires":[]},{"id":"8dc03c2edc7f3610","type":"function","z":"a12c69dd3cb81690","name":"make integer","func":"function updateBit(currentValue, bitNo, bitValue) {\n bitNo = parseInt(bitNo)\n const bitValueNormalized = (bitValue === \"true\" || bitValue === true || bitValue == \"1\") ? 1 : 0\n const clearMask = ~(1 << bitNo);\n return (currentValue & clearMask) | (bitValueNormalized << bitNo);\n}\n\nlet result = 0 // starting value\nlet data = msg.payload\nlet keys = Object.keys(data) // get prop names in payload data\n\n// loop prop names Bit_0, Bit_1, ...\nfor (let i = 0; i < keys.length; i++) {\n // use regex to grab the bit number from the prop name\n let key = keys[i]\n let bitRegex = /.*(\\d+).*/.exec(key)\n if (bitRegex && bitRegex.length) {\n let bitNo = bitRegex[1]\n // update the bit in result, based on values in the input data\n result = updateBit(result, bitNo, data[key])\n }\n}\n\nmsg.payload = result\nreturn msg","outputs":1,"timeout":0,"noerr":0,"initialize":"","finalize":"","libs":[],"x":1930,"y":560,"wires":[["01d225c3b918a471"]]}]

```

---

<div class="post-metadata">

**Author:** ![good\_mike](https://avatars.discourse-cdn.com/v4/letter/g/71e660/32.png) [@good\_mike](https://discourse.nodered.org/u/good_mike)\
**Post date:** [4 December 2023 08:56 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/8 "2023-12-04T08:56:31Z")

</div>

Great, I wouldn't have been able to do that on my own.  
Thank you very much!

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [18 December 2023 08:57 UTC](https://discourse.nodered.org/t/single-bits-to-integer/83382/9 "2023-12-18T08:57:05Z")

</div>

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