Serial ports (via USB) get blocked (?) - do I need to disconnect them?

[stephan from dublin]

I am running LV 7.1, using VISA config, read, write etc. to communicate through serial ports. For this purpose, I have a USB to serial converter, 8fold, which gives me eight serial ports.

It seems that, when the computer has been rebootet, I am able to use the serial ports, but after a while, when configering and reconfigering them, they get unusable.

Is it necessary, once a serial port has been configured, to release it, so it can be used for another configuration/funciton?

Is there a VI to release a serial port?

Thanks for your help!

[heimo]

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@stephan from dublin wrote:
I am running LV 7.1, using VISA config, read, write etc. to communicate through serial ports. For this purpose, I have a USB to serial converter, 8fold, which gives me eight serial ports.

It seems that, when the computer has been rebootet, I am able to use the serial ports, but after a while, when configering and reconfigering them, they get unusable.

Is it necessary, once a serial port has been configured, to release it, so it can be used for another configuration/funciton?

Is there a VI to release a serial port?

Thanks for your help!

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There is also a VI to close the VISA-Session called "VISA Close". Use this function after you have done all the work with your COMs. Maybe it helps !

Greetings Heimo

[OZI]

we are using USB for a Touch controller. After a little time it can be possible that the USB is also blocked.
We found two reasons for this:

1) The power options of the computer. If they are available and the computer tries to power down, the USB connection get blocked. (If a application is running the power options start to shut down the computer but the application denies this.)
2) Electro magnetical interference with other devices

Perhaps it helps

Greetings
Oliver