How to write the string array containing hex commands to serial out node without buffer on node v0.10.40/node-red v0.15.2

General
1

I need to write the string array of hex commands to the serial supported RS232 device, I am trying to send it using a buffer but it is not available in Node-Red version 0.10.40. Could anyone suggest me some possible ways and ideas to send this data? I welcome your suggestions and thank you in advance!

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2

There is no "Node-Red version 0.10.40". Do you mean NodeJS? :thinking:

If so, that version is pretty outdated and no longer supported by Node-RED.

Which version of Node-RED are you running? You can see it in the console or at the bottom of the editor settings menu.

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But apart from that, you can use a function node to achieve the same.

Have a look at the Buffer docs and the Buffer.from() method to create a Buffer from an array.

As an example:

msg.payload = Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);
return msg;
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4

Thank you for your reply. I admit that I am a beginner but It is strange because in the console the version is 0.15.2

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, but the node -v command shows 0.10.40.

5

Oof, that's a pretty old version, especially if you are capable of running Node v10 on this device. Can you explain how you installed node-red, and if it would be possible to upgrade to a newer version?
Edit: sorry I read that wrong, Node v0.10 is far older. Still the same question, can you explain how you installed it/what platform you're running on?

6

I did not install the node-red by myself, actually; I am working on the wireless gateway device in which the node-red of that version is pre-installed.

7

I tried to implement your idea but this error message came, do you know where have I done something wrong?

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8

Sadly, that won't work, because of this small note:

When running node v0.10 (EOL 2016), you're unable to use the Buffer functionality.
As is shown with the error displayed:

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9

You are right because in the latest version of node-red I got the expected output. Do you have any idea what should I do now to implement same thing in the old version? image,

10

You can go back to the 0.10.x version of the Buffer docs to see the available functions: https://nodejs.org/docs/latest-v0.10.x/api/buffer.html

I think the following would do it:

msg.payload = new Buffer([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);
return msg;
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11

Thank you, I go through the Buffer docs. By the way, your code generated this output
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