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TCP/IP Socket Using VISA Warning - Unable to Read Any Data

These remedies apply to the case when you receive no data and you get this warning message:

'visa' unable to read any data

When using the VISA TCP/IP Socket for:

  • Reading ASCII (text) data using the fscanf, fgets, or fgetl functions

  • Reading binary data using the fread function

  • Reading binblock data using the binblockread function

these are possible causes and remedies:

CauseSolution
An invalid command was sent to the device, so there is a problem reading the response to the command.Check your device manual for proper command formatting.
The write EOSCharCode is incorrect.Verify that the EOSCharCode property is set to the value required by your device.
Your device did not receive the command because either the TCP/IP remote host address or the remote port is incorrect.Verify that the device is at the remote host address that you specified, and is listening on the remote port that you specified when you created the visa object. For more information about communication settings, see Create TCP/IP Client and Configure Settings and Write and Read Data over TCP/IP Interface.

More Troubleshooting Help

For more information about troubleshooting the TCP/IP Socket using VISA interface, including supported platforms, adaptor requirements, configuration and connection, and other troubleshooting tips, see Troubleshooting TCP/IP Client Interface and Troubleshooting IVI and Quick-Control Interfaces.