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Can I set XonLimit and XoffLimit for serial port communication?

@mhd.gar  已寫:


I have similar problem . I am using Advanced serial write and Read example and I want to change some of those initializations .I have software that it shows what the original program is sending .Due to those commands i want to change followings : 

1- XonLimit and XoffLimit   (in original program it has been set to  2048 and  512 resp. but in LabVIEW i cann't set these values .

2- I want to set DTR and  RTS off

3- set these  ReadInterval=500, ReadTotalTimeoutMultiplier=2000, ReadTotalTimeoutConstant=0, WriteTotalTimeoutMultiplier=0, WriteTotalTimeoutConstant=0

4- In/out queue size 1000/1000


Many thanks if anybody help me .


I have the same problem

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Message 11 of 13

Hi, I'm having the same problem and need to set the xonlimit and xofflimit. I looked through the examples but can't find anything where these parameters are set. Can you elaborate a bit or maybe give a screenshot or these properties ?

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Message 12 of 13

Do you really need control over the XON/XOFF limits?


If you need more control over the serial port settings: Refer to 

This thread is about the DTR line, but the library has a VI for the XON/XOFF limits. This is much more complicated because this VI "comm" was primary made for full control over all possible flow control options. VISA has three settings for XON/XOFF (enable/disable, XON character, XOFF character), while this VI gives you control over all 7 settings for XON/XOFF mode and you have to set them all correctly.


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Message 13 of 13