• When using Windows 2000/XP, I cannot install the Cardbus drivers because the device manager tells me that I do not have enough resources to run this device.

Answer: This sometimes happens with some cards, and to determine if it is the card or the Chassis that is having the problem the best thing to do is to take the cards out of the chassis and then boot up. Go into Control Panels -> System -> Hardware -> Device Manager. Select "view by connection" in the View Menu. Open the items with a + in front of them until you locate the PCI bus, open that. Then open items with a + in front and scroll down until you locate the Cardbus Controllers (Cardbus PCI bridge). One of them should have a + in front of it, open that and you should fine the DEC 21152 PCI Bridge device. Under that (open the + in front of it) you should find the DEC 21150 PCI Bridge Device. If they have no 'bangs' (Yellow Exclamation points) in front of them, then the driver properly loaded and configured the expansion chassis. If they have a bang in front of them, then it is possible that the MAGMA Cardbus driver did not install correctly, or has not been installed, on this laptop. In either case, let us first take the system back to the way it was when we first started up and make sure we have a clean install of the driver. To do that, do the following: Since we are in the Device Manager currently, click on the 21150 PCI bridge and remove it from the system, then do the same thing for the 21152 PCI bridge. Close out of System, and select the Add/Remove Programs control panel and remove the MAGMA (or Mobilty) Cardbus Driver. Then Shut down the computer to power off state. With the chassis completely connected and powered up, power up the computer. If all goes as it should, the system should find new hardware, installing the drivers for the device automatically, and ask you to reboot (it knows how to drive the PCI bridge so it should not ask you for any drivers at this time). Shut the computer down to power off, then boot it back up. This allows the registry entry we just made to be saved and the whole registry to be loaded cleanly. Now we want to install the MAGMA Cardbus Driver software. In older versions it will ask you to restart your system, when it asks you this, answer no and then hit the 'start' -> 'shutdown' sequence to power down the computer instead.. Then power up the computer again. This time is should again find new hardware, if it asks you for drivers, it should be for drivers for whatever application cards that you have installed in the chassis, as the system should already know how to drive the second bridge and have the drivers to install automatically. You can go into the device manager at this point and the bridges should show up under the appropriate Cardbus Controller as a DEC21152 PCI Bridge, and under that, a DEC21150 PCI bridge without a Bang in front of it (Yellow Exclamation Point). If so, then all is well and you are up and running. At this point you should be ready to add your PCI REGIT boards.  See the Puma driver installation instructions for more information.

Back to FAQs

• What is Overlap Processing?

Answer: Assume we are collecting and analyzing 10 kHz data with 25.6 kHz sampling frequency, and we wish to calculate a 1 k FFT. The data collection time (also known as Time Window) for collecting 1024 time samples is exactly 40 msec. If the FFT processor calculates and displays a spectrum in 10 msec, then it will sit and wait for 30 msec until the acquisition of the next block is completed. Once the first block is collected, rather than waiting for the next block to be fully collected, we can proceed to calculate a new spectrum by using part of the data from the new block and part of the data from the old block. If the data is stationary, there is no reason why we cannot `mix' data from the two blocks. With the values given above, we could initiate a new FFT calculation by using 75% of the previous block and 25% of the latest one. We would then be performing what is called 75% overlap processing and our apparent processing time (after the first block) would be 10 msec per spectrum, rather than 40 msec. Where this process becomes even more significant is when we are operating at very low frequencies, i.e. below 1 kHz, when we want to calculate large transforms, i.e. greater than 1 k, or when we want to calculate many spectra in order to do averaging. For example, let's assume we are operating in a 100 Hz frequency range and wish to calculate 16 averages. The data collection time is 4 sec and, without overlap processing, we need 64 sec. With 75% overlap, we need 4 sec for the first block and 1 sec for each successive one, or 4x1 + 1x15 = 19 sec to perform the same task.

Back to FAQs