National Instruments PC/104-GPIB Getting Started page 25

Selecting the Interrupt Request Line
Note:
© National Instruments Corporation
PC/104-compatible systems have a series of interrupt request lines
available to devices. Devices use interrupts to get immediate service from
the CPU for asynchronous events. Your GPIB hardware and the
NI-488.2M software use interrupts to get service from the CPU when
necessary.
The GPIB software for Windows NT requires that the PC/104-GPIB be
configured to use an interrupt request line.
By default, the PC/104-GPIB is configured to use interrupt request
line 11. If this setting conflicts with another device in your system, if you
are installing the PC-104-GPIB in an 8-bit stack, or if you need to install
more than one PC/104-GPIB, follow these steps to reconfigure the
interrupt request line:
1. Choose a new interrupt request line (IRQ) setting.
If you are installing the PC/104-GPIB in a 16-bit stack, you can
configure it to use any of the following interrupt lines: IRQ3, 4, 5, 6,
7, 9, 10, 11, 12, 14, or 15. You might not want to select interrupt
lines 6 or 14 because the diskette drive controller typically uses
interrupt line 6 and the hard disk drive controller uses interrupt
line 14 on most systems.
If you are installing the PC/104-GPIB in an 8-bit stack, the only
interrupt lines available to you are 3, 4, 5, 6, and 7.
If you are installing more than one PC/104-GPIB, each module must
use a unique IRQ level.
2. Find the jumpers at W1 and W3 that set the interrupt request line.
The jumpers are located on the lower edge of your PC/104-GPIB.
Refer to the parts locator diagram, Figure 2-2.
3. Change the jumper settings to configure the PC/104-GPIB to the new
interrupt request line.
To use lines 10, 11, 12, 14, or 15, use the jumper block shown in
Figure 2-4. To use interrupt lines 3, 4, 5, 6, 7, or 9, use the jumper
block shown in Figure 2-5.
Chapter 2 Hardware Configuration and Installation
2-9 PC/104-GPIB for Windows NT