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Instrument Control (GPIB, Serial, VISA, IVI)

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visa write unsuccessfully

Hi there, 

 

Currently i integrate the ft232r usb uart ic chip with labview platform.

 

I am conducting a basic test to check if the chip can communicate well with labview.

 

The chip is set to send a feedback signal once it successfully recieve the command. eg. I sent "ST0201;" to the chip then get a feedback signal "535430323031"

 

I test it succefully on a third party serial communication software (attached the capture pic below), but it seems doent' work on labview.

 

But when it is connected with labview " continuous write and read.vi", my command seems cannot sent succeffully to the icchip.but the signals in the  first row "nRF24L01 USB Dongle" means labview can recieve initial data from chip. So i can conclud that my chip actullay connect ok with labview

 

I check for a long time then found that my chip is only supportable for byte command.

 

Is it the problem that the command type sent from labview is string so that my chip cannot recognize that ?

 

Or is it any other problem?

 

Thanks

 

Regards,

Newbie from singapore

 

 

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Do you really need end characters?

I suppose not, so switch off the read and write end characters!

 

Maybe in this example NI should indicate better what off and on is with these switches

greetings from the Netherlands
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HI,

 

thanks for your reply.

 

Followed by your guidance, I turn off both the Read and Write termination. But still cannot receive any feedback data after send command.

 

I thought it is bcs the chip can only receive byte command

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 I sent "ST0201;" to the chip then get a feedback signal "535430323031"


 

 

Do you realize that "535430323031" is the hexadecimal representation of the ASCII characters "ST0201" ?

 

Since the semicolon ";" (hex 3B) did not get echoed, I wonder if that is being used as a termination character? What information do you have about how the remote device communicates? Perhaps you need the correct termination characters. Try setting the termination character to semicolon ":".

 

Lynn

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