# Adding two values

**URL:** <https://discourse.nodered.org/t/adding-two-values/32784>\
**Category:** General\
**Created:** [12 September 2020 16:32 UTC](https://discourse.nodered.org/t/adding-two-values/32784 "2020-09-12T16:32:29Z")\
**Posts on this page:** 20\
**Page:** 2

<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [25 September 2020 13:29 UTC](https://discourse.nodered.org/t/adding-two-values/32784/21 "2020-09-25T13:29:20Z")

</div>

@Steve-Mcl you are totaly right 🥴

 ![1](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/d/ed58d01ec7da42dc4907e329e0dae7509dabddc6.png)

I got 2 problems  
yellow: if the DC-Voltage get over "65535" -\> 655,35V the Voltage begins at 5-10V.

red: if reactive power get negative, the value get on very high like 65500.

I need an Explanation what i have to do with the buffer parser

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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:** [25 September 2020 13:36 UTC](https://discourse.nodered.org/t/adding-two-values/32784/22 "2020-09-25T13:36:43Z")

</div>

I gave you detailed info and a flow [here](https://discourse.nodered.org/t/adding-two-values/32784/14).

I also said you might need to chose the (be) versions or do a swap16 on the data.

All you replied was "

> [@Becker](#):
>
> your flow doesn´t work

I can assure you it does - the screen shot shows it works (albeit with zero values)

Give it a go and if / when you get stuck, I can help you figure it out.

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<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [25 September 2020 14:03 UTC](https://discourse.nodered.org/t/adding-two-values/32784/23 "2020-09-25T14:03:26Z")

</div>

i want to **understand** the problem, and only "buffer parser" the necessary values.

I understand the values are S32 -\> 32bit signed -\> 16bit positive and 16bit negative.

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<div class="post-metadata">

**Author:** ![UnborN](https://avatars.discourse-cdn.com/v4/letter/u/4491bb/32.png) [@UnborN](https://discourse.nodered.org/u/UnborN)\
**Post date:** [25 September 2020 18:00 UTC](https://discourse.nodered.org/t/adding-two-values/32784/24 "2020-09-25T18:00:16Z")

</div>

Hi Becker,

Did you manage to get buffer parser working ?

I was testing today aIso with an Energy Meter, my brother had, that uses 32bit values.  
in my case it was 32bit float and buffer parser read it with no problem.  
like a hot knife through butter 😄

Try every combination 😉  
int32be, int32le, swap, no swap till you get the result  
just make sure you are sending the modbus **msg.responseBuffer.buffer** to it.

By the way is this the link to your devices modbus [documentation](https://www.sma.de/en/products/monitoring-control/modbus-protocol-interface.html) ?  
I went in **Downloads** then **Background Knowledge** and downloaded the first zip

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<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 09:25 UTC](https://discourse.nodered.org/t/adding-two-values/32784/25 "2020-09-26T09:25:02Z")

</div>

thank you,  
i used the windows app:  
 ![integer](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/0/c0a6431a6672cc091d7b19a808859c629c8bc271.png) ![decimal](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/f/5f9a99d337eb234ce4790047048aefe86487ee8d.png)

"decimal" is the wrong value, which I get in Node RED.  
"integer" ist the right, but no matter what I try in the buffer parser it doesn't work, always wrong values...

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<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 09:47 UTC](https://discourse.nodered.org/t/adding-two-values/32784/26 "2020-09-26T09:47:42Z")

</div>

the nearest result is:

 ![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/e/3e943273b3c958b94f09d287d5e11b54377833f5.png)

~ -230 is original value

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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:** [26 September 2020 09:54 UTC](https://discourse.nodered.org/t/adding-two-values/32784/27 "2020-09-26T09:54:34Z")

</div>

> [@Becker](#):
>
> ~ -230 is original value

- try swap16 in the "Byte Swap"
- try int32 (be) in the items list
- try different combinations of both

The issue is that manufactures use various formatting (big endian, little endian, etc) & if you dont know what that is, you have to use maths to figure it out (or play with the settings as suggested above and by Andy )

> [@UnborN](#):
>
> Try every combination 😉

---

<div class="post-metadata">

**Author:** ![UnborN](https://avatars.discourse-cdn.com/v4/letter/u/4491bb/32.png) [@UnborN](https://discourse.nodered.org/u/UnborN)\
**Post date:** [26 September 2020 09:59 UTC](https://discourse.nodered.org/t/adding-two-values/32784/28 "2020-09-26T09:59:32Z")

</div>

> [@Becker](#):
>
> i used the windows app:

and also try to find the correct documentation with the addresses .. dont "guess" the address by using that Master simulator 😉

---

<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 09:59 UTC](https://discourse.nodered.org/t/adding-two-values/32784/29 "2020-09-26T09:59:55Z")

</div>

![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/1/1/118375ec19287e536c5689e314d8c29bcec2e154.png)

 ![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/1/2/12f20af1612ae7d01f0af339076262fe443674d9.png)

 ![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/f/6fbf1088a2962cc84242fc8799773de42ee13f61.png)

 ![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/9/e96ed1db6119310103a2699a93250a5fbe05833b.png)

I´ve tried them all 😪

---

<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 10:03 UTC](https://discourse.nodered.org/t/adding-two-values/32784/30 "2020-09-26T10:03:40Z")

</div>

the documentation:

> **[dok.zip](https://drive.google.com/file/d/1xmHvv0x5smtx4wXkkHLJzk2UKSezOtgq/view?usp=sharing)**
>
> Google Drive file.

reactive power is number "31497"

---

<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:** [26 September 2020 10:03 UTC](https://discourse.nodered.org/t/adding-two-values/32784/31 "2020-09-26T10:03:52Z")

</div>

Not quite.

Often implementations of modbus mess up what is the first value. Sometimes it's 0, sometimes it's 1. Sometimes it's 4000 sometimes it's 40000 etc

For example, offset 1 might be where your data is (not offset 0)

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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:** [26 September 2020 10:08 UTC](https://discourse.nodered.org/t/adding-two-values/32784/32 "2020-09-26T10:08:02Z")

</div>

Do me a favour.

- Set fixed values in your simulator & post a screenshot showing what values you entered.
- Operate your flow and capture the debug output of the modbus node by clicking the copy button on the debug output. Make sure debug node is set to **show complete message**.

Using debug to copy value...  
 ![Vmz3Zy8Buu](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/9/392acfb68c5a638f774f86fda6d22fb96f0bab5f.gif)

Post results below.

`````  
`like this`  
`````

I will show you how to do it.

---

<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 10:18 UTC](https://discourse.nodered.org/t/adding-two-values/32784/33 "2020-09-26T10:18:08Z")

</div>

I´ve no simulator 🙄

 ![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/6/963e4add4262463322253b3d287b432571e46e1d.png)  
Offset 1 is right, I choosed it before it goes in the buffer parser!

---

<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:** [26 September 2020 10:20 UTC](https://discourse.nodered.org/t/adding-two-values/32784/34 "2020-09-26T10:20:06Z")

</div>

> [@Becker](#):
>
> I choosed it before it goes in the buffer parser!

and there is your problem

the data required to be fed into the buffer parser is the data from the modbus node - not your hacked function (your function discards important parts of the data that make up a singed 32 bit value)

Just like i posted in my demo last week and just like Andy said

> [@UnborN](#):
>
> just make sure you are sending the modbus **msg.responseBuffer.buffer** to it

---

<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:** [26 September 2020 10:21 UTC](https://discourse.nodered.org/t/adding-two-values/32784/35 "2020-09-26T10:21:26Z")

</div>

Here is my complete post again - try it & see where you get to...

* * *

Hi again, as mensioned earlier, this is how you can do it with buffer parser...

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/0/60bf7ef0baeb69e419ebed9e7d28aab13eed11a9.png)  
(obviously I dont have your invertor so all values are simulated - zero)

this is the flow i did...

```auto
[{"id":"3c70a20c.01d53e","type":"inject","z":"15164b61.40f905","name":"","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":220,"y":300,"wires":[["bb340a9c.a81c58","7bdb6cd4.f23b24","58e3fd6c.ca7b04","4d07d7f8.99b288"]]},{"id":"bb340a9c.a81c58","type":"modbus-getter","z":"15164b61.40f905","name":"30773 ~ 30869","showStatusActivities":false,"showErrors":true,"logIOActivities":false,"unitid":"","dataType":"InputRegister","adr":"30773","quantity":"96","server":"7b9a0315.71ca9c","useIOFile":false,"ioFile":"","useIOForPayload":false,"emptyMsgOnFail":false,"keepMsgProperties":false,"x":480,"y":220,"wires":[["768c153b.df699c"],[]]},{"id":"7bdb6cd4.f23b24","type":"modbus-getter","z":"15164b61.40f905","name":"30953 ~ 30955","showStatusActivities":false,"showErrors":false,"logIOActivities":false,"unitid":"","dataType":"InputRegister","adr":"30953","quantity":"2","server":"7b9a0315.71ca9c","useIOFile":false,"ioFile":"","useIOForPayload":false,"emptyMsgOnFail":false,"keepMsgProperties":false,"x":480,"y":280,"wires":[["5e0a1ec.aeb7ce"],[]]},{"id":"58e3fd6c.ca7b04","type":"modbus-getter","z":"15164b61.40f905","name":"31253 ~ 31259","showStatusActivities":false,"showErrors":false,"logIOActivities":false,"unitid":"","dataType":"InputRegister","adr":"31253","quantity":"6","server":"7b9a0315.71ca9c","useIOFile":false,"ioFile":"","useIOForPayload":false,"emptyMsgOnFail":false,"keepMsgProperties":false,"x":480,"y":340,"wires":[["7cdd5a8a.43b644"],[]]},{"id":"4d07d7f8.99b288","type":"modbus-getter","z":"15164b61.40f905","name":"31447 ~ 31499","showStatusActivities":false,"showErrors":false,"logIOActivities":false,"unitid":"","dataType":"InputRegister","adr":"31447","quantity":"52","server":"7b9a0315.71ca9c","useIOFile":false,"ioFile":"","useIOForPayload":false,"emptyMsgOnFail":false,"keepMsgProperties":false,"x":480,"y":400,"wires":[["b7162329.e0cc4"],[]]},{"id":"768c153b.df699c","type":"buffer-parser","z":"15164b61.40f905","name":"","data":"responseBuffer.buffer","dataType":"msg","specification":"spec","specificationType":"ui","items":[{"type":"int32le","name":"PDC2","offset":0,"length":1,"offsetbit":0,"mask":""},{"type":"int32le","name":"PAC2","offset":4,"length":1,"offsetbit":0,"mask":""},{"type":"int32le","name":"Pbez","offset":184,"length":1,"offsetbit":0,"mask":""},{"type":"int32le","name":"Pein","offset":188,"length":1,"offsetbit":0,"mask":""}],"swap1":"swap16","swap2":"","swap3":"","swap1Type":"swap","swap2Type":"swap","swap3Type":"swap","msgProperty":"payload","msgPropertyType":"str","resultType":"keyvalue","resultTypeType":"output","multipleResult":false,"setTopic":true,"x":670,"y":220,"wires":[["bc60faef.9b6c08","15f17a3a.bf22a6","c2e5e0ec.242a1","865fdaa3.0ff7b8","52e8c22d.52cb6c"]]},{"id":"5e0a1ec.aeb7ce","type":"buffer-parser","z":"15164b61.40f905","name":"","data":"responseBuffer.buffer","dataType":"msg","specification":"spec","specificationType":"ui","items":[{"type":"int32le","name":"T2","offset":0,"length":1,"offsetbit":0,"mask":""}],"swap1":"swap16","swap2":"","swap3":"","swap1Type":"swap","swap2Type":"swap","swap3Type":"swap","msgProperty":"payload","msgPropertyType":"str","resultType":"keyvalue","resultTypeType":"output","multipleResult":false,"setTopic":true,"x":670,"y":280,"wires":[["ed2f8fed.778a1","121cd028.592a7"]]},{"id":"7cdd5a8a.43b644","type":"buffer-parser","z":"15164b61.40f905","name":"","data":"responseBuffer.buffer","dataType":"msg","specification":"spec","specificationType":"ui","items":[{"type":"int32le","name":"UL1","offset":0,"length":1,"offsetbit":0,"mask":""},{"type":"int32le","name":"UL2","offset":4,"length":1,"offsetbit":0,"mask":""},{"type":"int32le","name":"UL3","offset":8,"length":1,"offsetbit":0,"mask":""}],"swap1":"swap16","swap2":"","swap3":"","swap1Type":"swap","swap2Type":"swap","swap3Type":"swap","msgProperty":"payload","msgPropertyType":"str","resultType":"keyvalue","resultTypeType":"output","multipleResult":false,"setTopic":true,"x":670,"y":340,"wires":[["e77c39b2.ab0da8","96e6d1a4.95cf5","b7d0340e.8bd868","25aca7ac.e71e78"]]},{"id":"b7162329.e0cc4","type":"buffer-parser","z":"15164b61.40f905","name":"","data":"responseBuffer.buffer","dataType":"msg","specification":"spec","specificationType":"ui","items":[{"type":"int32le","name":"Hz","offset":0,"length":1,"offsetbit":0,"mask":""},{"type":"int32be","name":"var","offset":50,"length":1,"offsetbit":0,"mask":""}],"swap1":"swap16","swap2":"","swap3":"","swap1Type":"swap","swap2Type":"swap","swap3Type":"swap","msgProperty":"payload","msgPropertyType":"str","resultType":"keyvalue","resultTypeType":"output","multipleResult":false,"setTopic":true,"x":670,"y":400,"wires":[["d8a23fa6.0a779","d0023be2.999bb8","2405d4f1.155f9c"]]},{"id":"bc60faef.9b6c08","type":"debug","z":"15164b61.40f905","name":"parser1","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","x":920,"y":60,"wires":[]},{"id":"15f17a3a.bf22a6","type":"ui_text","z":"15164b61.40f905","group":"8a11e8c7.342528","order":1,"width":0,"height":0,"name":"P-ein","label":"<font color=green> Leistung Einspeisung","format":"{{msg.payload.Pein}} W","layout":"row-spread","x":910,"y":100,"wires":[]},{"id":"c2e5e0ec.242a1","type":"ui_text","z":"15164b61.40f905","group":"8a11e8c7.342528","order":2,"width":0,"height":0,"name":"P-bez","label":"<font color=red> Leistung Bezug","format":"{{msg.payload.Pbez}} W","layout":"row-spread","x":910,"y":140,"wires":[]},{"id":"865fdaa3.0ff7b8","type":"ui_text","z":"15164b61.40f905","group":"5be273cb.ceaddc","order":1,"width":0,"height":0,"name":"P-AC2","label":"Leistung AC","format":"{{msg.payload.PAC2}} W","layout":"row-spread","x":910,"y":180,"wires":[]},{"id":"52e8c22d.52cb6c","type":"ui_text","z":"15164b61.40f905","group":"5be273cb.ceaddc","order":2,"width":0,"height":0,"name":"P-DC2","label":"<font color=orange> Leistung DC","format":"{{msg.payload.PDC2}} W","layout":"row-spread","x":910,"y":220,"wires":[]},{"id":"ed2f8fed.778a1","type":"ui_text","z":"15164b61.40f905","group":"5be273cb.ceaddc","order":3,"width":0,"height":0,"name":"T2","label":"Temperatur","format":"{{msg.payload.T2}} °C","layout":"row-spread","x":910,"y":320,"wires":[]},{"id":"121cd028.592a7","type":"debug","z":"15164b61.40f905","name":"parser2","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","x":920,"y":280,"wires":[]},{"id":"e77c39b2.ab0da8","type":"ui_text","z":"15164b61.40f905","group":"8a11e8c7.342528","order":3,"width":0,"height":0,"name":"U-L1","label":"Spannung L1","format":"{{msg.payload.UL1}} V","layout":"row-spread","x":910,"y":420,"wires":[]},{"id":"96e6d1a4.95cf5","type":"ui_text","z":"15164b61.40f905","group":"8a11e8c7.342528","order":4,"width":0,"height":0,"name":"U-L2","label":"Spannung L2","format":"{{msg.payload.UL2}} V","layout":"row-spread","x":910,"y":460,"wires":[]},{"id":"b7d0340e.8bd868","type":"ui_text","z":"15164b61.40f905","group":"8a11e8c7.342528","order":5,"width":0,"height":0,"name":"U-L3","label":"Spannung L3","format":"{{msg.payload.UL3}} V","layout":"row-spread","x":910,"y":500,"wires":[]},{"id":"25aca7ac.e71e78","type":"debug","z":"15164b61.40f905","name":"parser3","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","x":920,"y":380,"wires":[]},{"id":"d8a23fa6.0a779","type":"ui_text","z":"15164b61.40f905","group":"8a11e8c7.342528","order":6,"width":0,"height":0,"name":"Hz","label":"Frequenz","format":"{{msg.payload}} Hz","layout":"row-spread","x":910,"y":600,"wires":[]},{"id":"d0023be2.999bb8","type":"ui_text","z":"15164b61.40f905","group":"5be273cb.ceaddc","order":3,"width":0,"height":0,"name":"var","label":"Blindleistung","format":"{{msg.payload}} var","layout":"row-spread","x":910,"y":640,"wires":[]},{"id":"2405d4f1.155f9c","type":"debug","z":"15164b61.40f905","name":"parser4","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","x":920,"y":560,"wires":[]},{"id":"870d2fa5.fa314","type":"comment","z":"15164b61.40f905","name":"STP6.0-3AV-40","info":"","x":220,"y":260,"wires":[]},{"id":"7b9a0315.71ca9c","type":"modbus-client","z":"","name":"STP6.0","clienttype":"tcp","bufferCommands":true,"stateLogEnabled":false,"queueLogEnabled":false,"tcpHost":"192.168.168.50","tcpPort":"502","tcpType":"TPC-RTU-BUFFERED","serialPort":"/dev/ttyUSB","serialType":"RTU-BUFFERD","serialBaudrate":"9600","serialDatabits":"8","serialStopbits":"1","serialParity":"none","serialConnectionDelay":"100","unit_id":3,"commandDelay":200,"clientTimeout":1000,"reconnectOnTimeout":true,"reconnectTimeout":2000,"parallelUnitIdsAllowed":true},{"id":"8a11e8c7.342528","type":"ui_group","z":"","name":"Energy Meter","tab":"78892c6f.892384","order":2,"disp":true,"width":"6","collapse":false},{"id":"5be273cb.ceaddc","type":"ui_group","z":"","name":"Sunny Tripower","tab":"78892c6f.892384","order":2,"disp":true,"width":"6","collapse":false},{"id":"78892c6f.892384","type":"ui_tab","z":"","name":"Photovoltaik","icon":"dashboard","order":2,"disabled":false,"hidden":false}]

```

These are how i decided to group the reads up into 4 parts & the offsets I used in the buffer parser...

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/0/d0802f6ba1bf98d1cdfd66300e02b7a27a50b42e.png)

NOTE: I couldnt find an exact manual but [this one](http://files.sma.de/dl/2585/WEBBOX-MODBUS-TB-en-19.pdf) suggests values are S32 (Signed 32 bit integers)

So if you find the values comming out of `buffer parser` values are not correct, then simply change the settings...

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/5/455be9091c4941f4602e108745140e71b1c7e933.png)

---

<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 10:34 UTC](https://discourse.nodered.org/t/adding-two-values/32784/36 "2020-09-26T10:34:00Z")

</div>

![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/1/1/118c103418249c0ed6fe12bbe355339b95d58e91.png)

tried all 4 combinations in your flow

---

<div class="post-metadata">

**Author:** ![UnborN](https://avatars.discourse-cdn.com/v4/letter/u/4491bb/32.png) [@UnborN](https://discourse.nodered.org/u/UnborN)\
**Post date:** [26 September 2020 10:35 UTC](https://discourse.nodered.org/t/adding-two-values/32784/37 "2020-09-26T10:35:58Z")

</div>

good thing you send the screenshot .. I think its better to make a new start on a new tab/flow.  
Copy paste your nodes from the existing tab to a new one, delete whatever is after the Modbus flex getters nodes and disable the old flow.

Also to fully understand what a buffer is put a complete message debug node directly after the Modbus flex getter.  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/2/4/2475c56eac1cb83606e374b2d62bb746581c6fa6.png)

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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:** [26 September 2020 10:37 UTC](https://discourse.nodered.org/t/adding-two-values/32784/38 "2020-09-26T10:37:53Z")

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1. get me some data to play with...  

2. copy the values...  
 ![Vmz3Zy8Buu](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/9/392acfb68c5a638f774f86fda6d22fb96f0bab5f.gif)

3. Paste the results in your reply  
`````  
`like this`  
`````

4. tell me what the values SHOULD be

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<div class="post-metadata">

**Author:** ![UnborN](https://avatars.discourse-cdn.com/v4/letter/u/4491bb/32.png) [@UnborN](https://discourse.nodered.org/u/UnborN)\
**Post date:** [26 September 2020 10:44 UTC](https://discourse.nodered.org/t/adding-two-values/32784/39 "2020-09-26T10:44:40Z")

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a side note .. by the way from the documentation

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/2/3/23dc50669bbb00b2d189803e01f2999815a21a09.png)

take in consideration that some values may be S32 others unsigned 32

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<div class="post-metadata">

**Author:** ![Becker](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Becker](https://discourse.nodered.org/u/Becker)\
**Post date:** [26 September 2020 10:46 UTC](https://discourse.nodered.org/t/adding-two-values/32784/40 "2020-09-26T10:46:49Z")

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well it´s the same like before:

 ![grafik](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/f/2/f21a31695b429ddce8c53e14c7eb6f7e9a167831.png)

var should be approximately -350 (-200 to -400)

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