User manual

Chapter 4: PowerDAQ Software (SDK)
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When starting out, first recognize that a driver for a data
acquisition card differs from one for a printer, CD-ROM or
other peripheral in one fundamental way: real-time operation. A
printer can wait before it gets the next data to print; a CD-ROM
can pause for a short while to let some other activity go on. A
data-acq board, though, typically is collecting data continuously
and can pause only as long as its onboard FIFO can store
intermediate results. If this buffer overflows, incoming data is
lost.
The interrupt can be assigned by the BIOS of your PC and if
allowed, it might be re-assigned during the operation system
boot up process. If you have an Advanced Interrupt Controller
on your motherboard – just enable it in the BIOS – this will
allow you to use more than 16 generic interrupt lines. If not –
use the manual settings to assign the interrupt to the PCI slot
where PowerDAQ board is installed.
Modern motherboards can easily contain four, five or even more
PCI slots plus integrated PCI devices such as network cards
and/or video card. Usually only three of them are independent
and do not share interrupts you’re your video, disk or network
subsystem. Please refer to your motherboard manual to find out
which slots share interrupts and cannot be used for fast data
acquisition.