Sending an \r to TCP devices

General
1

Hello,

I'm trying to connect to an external device using the TCP/IP node. I need to send the command string ON followed by a carrage return \r. I've tried sending ON\r using the exchnage function and the inject function but this doesn't seem to work?

I can connect to the device in other programming languages such as labVIEW soi know the command is correct and the device is functioning.

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The TCP node indicates that it is connected to the device and a debug node confirms the string has been past correctly but the device does not seem to accept the command - is there another way to send a carrage return so its not part of the string?

Many thanks!
Ollie

2

Change your inject node to the JSON type and input
"ON\r"
that should work.

3

Fantastic - I thought it would be something simple! I couldn't get it to work using the inject node as JSON but could using the change node - why is that?

4

Show us how you configured the Inject node (when you configured it as suggested) and what it gives if you feed that into a Debug node.

5

Should work the same:

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6

When building raw tcp or serial data strings, I've generally used the inject node set to Buffer mode...

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Click on the three dots ... on the right end of the input field to open the buffer editor -- then just type the string and hit the Enter key to add the "\r" to the end of the string:

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You can see the trailing return 0A character in the bottom window...

7

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