detecting device

[Muthuraman]

Dear All,

Can anyone tell me how to determine the status of all the devices in a PXI Chassiss (Currently in use or not)?

Regards,

Muthuraman S

[Jochen]

Muthuraman,

what exactly do you mean by "currently in use or not"? Do you want to know, if the devices are detected by their drivers or do you need to know if an application is currently accessing the devices?

In the latter case there is not a trivial answer to it. In fact a PXI system could contain a lot of different  types of devices (e. g. multifunction DAQ, motion control, machine vision, fieldbus interfaces, modular instruments,...). All these devices are supported by their own driver and some devices or some parts of the devices can be used at the same time in different applications.

Please provide more specific information about your hardware and what you are trying to accomplish.

Thanks and kind regards,m

Jochen Klier

National Instruments

[Muthuraman]

                  Klier,

                  My Main objective is to show to the user the following:

                  Device x (PXI)   -   [Uninitialized | Initialized | Running ]

                  -     Uninitialized, no driver info has been loaded into memory, no handle has been allocated by labview.

-          Initialized, idling.  Low level driver has been loaded into memory, handle has been allocated by labview, no task is assigned.

-          Running, busy executing a task.

Each device in the PXI need to be showed to the user with either of above states.

Regards,

Muthuraman S

[Jochen]

Thank you for the information. As I have already told you, this is not a trivial task and it requires very low level programming and probably different approaches for different types of hardware. This is not a standard approach and I'm not sure if you will be able to complete this task successfully. So before you try to dig deeper into this task I highly recommend to seriously rethink your concepts and try to find an easier way that follows more standardized methods.

If you can't think of a better way to design your application, please provide detailed information about what exactly you are trying to accomplish and why you think you need to follow the approach that you have suggested, as well as a complete list of the PXI devices that you want to use.

Regards,

Jochen

[Muthuraman]

Klier,

The end user is using PXI chasis. He reports that when using one device alone (from the PXI card), the acquisition is getting distorted with little amount of Noise because of neighbouring devices. So he recommends us to uninitialize the neighbouring devices when acquiring in one particular device alone. 

Is it possible to uninitialize particular few devices alone in the PXI chasis? If so, how?

Your help is greatly appreciated.

Regards,

Muthuraman S

[Jochen]

Muthuraman,

I'm sorry, but again this is a question that can't be answered for all PXI devices in the market the same way. Some devices might be quite passive in terms of noise, if they are not initialized or in a reset mode, others might start their emissions as soon as they are powered. There is no common way to deinitialize a PXI device and some devices probably don't support such a feature at all.

In general I don't think, that this is a clean approach to deal with noise problems. Significant crosstalk between adjacent PXI devices sounds like a severe design problem of these products, but if you can't replace these devices, you better should try to find a configuration that minimizes this problem by swapping the modules in the chassis' slots.

Jochen