National Instruments Low-Cost Multifunction I/O Board for ISA Lab-PC+ - page 23

Chapter 2 Configuration and Installation
© National Instruments Corporation 2-7 Lab-PC+ User Manual
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DACK*
DRQ
W6
123
Figure 2-4. DMA Jumper Settings for Disabling DMA Transfers
Interrupt Selection
The Lab-PC+ board can connect to any one of the six interrupt lines of the PC I/O channel. The
interrupt line is selected by a jumper on one of the double rows of pins located above the I/O slot
edge connector on the Lab-PC+ (refer to Figure 2-1). To use the interrupt capability of the
Lab-PC+, you must select an interrupt line and place the jumper in the appropriate position to
enable that particular interrupt line.
The Lab-PC+ can share interrupt lines with other devices by using a tristate driver to drive its
selected interrupt line. The Lab-PC+ hardware supports interrupt lines IRQ3, IRQ4, IRQ5,
IRQ6, IRQ7, and IRQ9.
Note: Do not use interrupt line 6. Interrupt line 6 is used by the diskette drive controller on
most IBM PC and compatible computers.
Once you have selected an interrupt level, place the interrupt jumper on the appropriate pins to
enable the interrupt line.
The interrupt jumper set is W5. The default interrupt line is IRQ5, which you select by placing
the jumper on the pins in row 5. Figure 2-5 shows the default interrupt jumper setting IRQ5. To
change to another line, remove the jumper from IRQ5 and place it on the new pins.
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IRQ
W5
3 4 5 6 7 9
Figure 2-5. Interrupt Jumper Setting IRQ5 (Factory Setting)