# How to send a Break signal ( serial-node)

**URL:** <https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678>\
**Category:** General\
**Created:** [10 September 2020 07:48 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678 "2020-09-10T07:48:20Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![alex25](https://avatars.discourse-cdn.com/v4/letter/a/9fc29f/32.png) [@alex25](https://discourse.nodered.org/u/alex25)\
**Post date:** [10 September 2020 07:48 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/1 "2020-09-10T07:48:20Z")

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Hello All, I'm new with Node-Red and found that is a very interesting platform. I'm trying to log data from a serial communication device, but my problem is that to get a full set of data from the device I must sent to this a command that Must start with a Break Signal of at least 2ms. Some one could help me on how to achieve this? I already search and found many projects with serial-node, but no one that perform this activity.  
This is a great forum, I will appreciate any help. Thanks

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**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [10 September 2020 07:58 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/2 "2020-09-10T07:58:31Z")

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Hi,  
Sorry to be dense, but what is a break signal ? How do you send it normally without Node-RED ?

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**Author:** ![alex25](https://avatars.discourse-cdn.com/v4/letter/a/9fc29f/32.png) [@alex25](https://discourse.nodered.org/u/alex25)\
**Post date:** [10 September 2020 08:31 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/3 "2020-09-10T08:31:59Z")

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The `Break` signal must be of a duration longer than the time it takes to send a complete byte plus Start, Stop and Parity bits. In my case, at least 2ms.  
In RS232 a signal called a `Break` , which is caused by sending continuous Spacing values (no Start or Stop bits). When there is no electricity present on the data circuit, the line is considered to be sending `Break` .  
Is a long time that I don't do nothing like this, but I used some Simple routines on little's projects with PICs ( microprocessors).  
No clues to How to do this here...

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**Author:** ![alex25](https://avatars.discourse-cdn.com/v4/letter/a/9fc29f/32.png) [@alex25](https://discourse.nodered.org/u/alex25)\
**Post date:** [10 September 2020 08:39 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/4 "2020-09-10T08:39:21Z")

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This is an example of what I need:

```auto
SetCommBreak(port)
    Sleep(2); // 2 milliseconds - assuming 9600 baud. Pro-rata for others
    ClearCommBreak(port)

```

But as I said before I don't know from where start, thank for your time!

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**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [10 September 2020 08:54 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/5 "2020-09-10T08:54:48Z")

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OK - I'll admit I have never seen that before (despite playing with serial ports for more years than I care to recall) - and so no I know we don't support that right now. Would need digging into and working out how to tell the node to send that (and maybe other things like that) in a way that doesn't break existing users.  
Feel free to raise an issue against the serialport node - but I can't promise when we'll get a chance to look at it. (suggestions / help wanted ! )

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**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\
**Post date:** [10 September 2020 10:12 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/6 "2020-09-10T10:12:47Z")

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If my memory serves me correctly I believe that has to be handled at the UART level, so first you would have to find out if your hardware supported it. I don't know whether USB-Serial UARTS will do it, for example. There used to be serial devices that used a break input to reset things, but I don't remember seeing that for years.

.. following a quick google it appears the FTDI chips do support break.

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**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [10 September 2020 10:41 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/7 "2020-09-10T10:41:17Z")

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Yes the serialport library does seem to support it, but as I said we need to work out a way to a)call it in a sensible way and b) do that in a way that doesn’t break anything else.

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [9 November 2020 10:41 UTC](https://discourse.nodered.org/t/how-to-send-a-break-signal-serial-node/32678/8 "2020-11-09T10:41:31Z")

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