# Numeric value and serial communication
**URL:** https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326
**Category:** Dashboard
**Created:** [28 May 2024 18:25 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326 "2024-05-28T18:25:45Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@Nic](https://discourse.nodered.org/u/Nic)
#### Post date: [28 May 2024 18:25 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/1 "2024-05-28T18:25:45Z")
Hi all,
I'm quite newbye. I communicate via serial port with Arduino board, using Serial.read() function I am able to send single byte and Arduino works as "actuator" making many functions. Now I need to pass at Arduino a value inserted in my PC interface developed usind ui-dashboard nodes. Could someone advise me which is the best way to implement an easy communcation in order to pass integer values o string between Arduino and node-red?
Thanks in advance.
n
---
### Author:  [@marcus-j-davies](https://discourse.nodered.org/u/marcus-j-davies)
#### Post date: [28 May 2024 19:24 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/2 "2024-05-28T19:24:36Z")
Hi @Nic,
Sorry I can't quite grasp the last comment
_integer values o string between Arduino and node-red?_
Do you want to send a string containing numbers, or send numbers represented as bytes?
- As a string, send as is "12334456"
- As a collection of bytes
Lets assume a 32bit Integer
```auto
const num = 123456;
const buffer = Buffer.alloc(4); /* 4 bytes in a 32bit integer */
buffer.writeInt32BE(num, 0); /* Big Endian */
//buffer.writeInt32LE(num, 0); /* Little Endian */
msg.payload = buffer
return msg;
```
As for reading back integers passed to you as a byte array:
```auto
const int32 = msg.payload.readInt32BE(0); // Big Endian
```
For the 'easy way' - I do recommend however, looking at this node by our own @Steve-Mcl
> **[node-red-contrib-buffer-parser](https://flows.nodered.org/node/node-red-contrib-buffer-parser)**
>
> Node-red nodes to convert values to and from buffer/array. Supports Big/Little Endian, BCD, byte swapping and much more
---
### Author:  [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)
#### Post date: [28 May 2024 21:00 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/3 "2024-05-28T21:00:55Z")
I suspect the better solution is to always send and receive JSON. That way you can add meta data and perform different operations depending on the meta info.
---
### Author:  [@Nic](https://discourse.nodered.org/u/Nic)
#### Post date: [30 May 2024 13:16 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/4 "2024-05-30T13:16:44Z")
Hi, thanks for your advises. Finally I set the fw on arduino side in order to have something like a "metadata" where I include strings and integers. Working with the "string node" on node-red side I can divide the data in every part I need.
Thank you for the support.
n
---
### Author:  [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)
#### Post date: [30 May 2024 14:03 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/5 "2024-05-30T14:03:40Z")
> [@Nic](#):
>
> Working with the "string node" on node-red side I can divide the data in every part I need.
That is really not necessary & you are really re-inventing a perfectly good wheel that almost all of the JavaScript community already use - it is called **JavaScript Object Notation** (or JSON for short).
There are LOTS (and lots and lots) of reasons to go with a well established data interchange format (which JSON is) but the most important reasons are:
- It is highly extensible (future changes to your data will NOT break your project)
- It is literally built into JavaScript (`JSON.parse` / `JSON.stringify`) and built into Node-RED (the JSON node)
- It already exists and it works well
- Almost EVERY programmer knows exactly how to work with it (as opposed to some custom formatted string you invent)
- etc
- etc
---
### Author:  [@Nic](https://discourse.nodered.org/u/Nic)
#### Post date: [30 May 2024 14:28 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/6 "2024-05-30T14:28:51Z")
Steve, you are right but what you don't know is that I'm not able to work with JavaScript 😉
---
### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [29 June 2024 14:29 UTC](https://discourse.nodered.org/t/numeric-value-and-serial-communication/88326/7 "2024-06-29T14:29:12Z")
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