# Serial In / serial request node - start character

**URL:** <https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605>\
**Category:** Core Development\
**Created:** [11 August 2021 08:57 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605 "2021-08-11T08:57:08Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![SS-Akhilesh-Appala](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ss-akhilesh-appala/32/44482_2.png) [@SS-Akhilesh-Appala](https://discourse.nodered.org/u/SS-Akhilesh-Appala)\
**Post date:** [11 August 2021 08:57 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/1 "2021-08-11T08:57:08Z")

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HI  
In serial In/request node I am setting the option(Optionally wait for a start character of ) with the single character it is working as expected.  
but whenever I push the (multiple characters ) it stops working even data is being pushed from the device.  
is it expected or nodered wont be processing multiple characters in that field

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/c/7cbb9b8cd2804ed2a1bac33cddf5d6b3ab94a79b.jpeg)

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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:** [11 August 2021 09:20 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/2 "2021-08-11T09:20:50Z")

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Correct. It only looks for a single character. (The reason the field accepts more is to allow for \r or 0x48 etc)

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**Author:** ![SS-Akhilesh-Appala](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ss-akhilesh-appala/32/44482_2.png) [@SS-Akhilesh-Appala](https://discourse.nodered.org/u/SS-Akhilesh-Appala)\
**Post date:** [11 August 2021 10:29 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/3 "2021-08-11T10:29:48Z")

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Hi @dceejay,  
Isn't this a command, something like 'S' or 'ST' where the actual device behaves(sends) data based on the value  
S -- gives exact device data connected to serial port  
ST- when we click a button on the device.

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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:** [11 August 2021 10:31 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/4 "2021-08-11T10:31:36Z")

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No idea. Is that device specific maybe ?

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**Author:** ![SS-Akhilesh-Appala](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ss-akhilesh-appala/32/44482_2.png) [@SS-Akhilesh-Appala](https://discourse.nodered.org/u/SS-Akhilesh-Appala)\
**Post date:** [11 August 2021 10:36 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/5 "2021-08-11T10:36:30Z")

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Yes. serial devices has this behaviour, it works different with various begin data (which is like a command).  
Is this "optional wait for start character" works data which is coming from the device?  
example -- device is giving data from serial  
start character is "g" --\> then node gives data from giving data from serial?

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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:** [11 August 2021 10:47 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/6 "2021-08-11T10:47:42Z")

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Yes. As it says it waits until it sees that character in the serial stream then starts saving data until either the end character or a timeout or a number of characters, then sends that data on. And then repeats

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**Author:** ![SS-Akhilesh-Appala](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ss-akhilesh-appala/32/44482_2.png) [@SS-Akhilesh-Appala](https://discourse.nodered.org/u/SS-Akhilesh-Appala)\
**Post date:** [11 August 2021 10:53 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/7 "2021-08-11T10:53:33Z")

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Yeah, Got it @dceejay, Thanks for the clarification.

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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:** [10 October 2021 10:53 UTC](https://discourse.nodered.org/t/serial-in-serial-request-node-start-character/49605/8 "2021-10-10T10:53:56Z")

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