NuDAQ PET-48DIO, Руководство пользователя, Страница: 17 / 38

Installation
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2.8 Interrupt IRQ Level Setting
The PET-48DIO can connect to any one of the interrupt lines of the
PC I/O channel. The interrupt line is selected by the jumper
JP5 . If you
wish to use the interrupt capability of the PET-48DIO, you must select
an interrupt level and place the jumper in the appropriate position to
enable the particular interrupt line.
The default interrupt level is
IRQ5 , which is selected by placing the
jumper on the pins in row number 5. Figure 2.6 shows the default
interrupt jumper setting IRQ5. You should only remove the jumper
from IRQ5 to other pins, if you want to change to another IRQ level.
Note : Be aware that there is no other add-on card shares the same
interrupt level at the same system.
No Interrupt:
Interrupt level:
IRQ 5
(default setting)
JP5
3 4 5 7 9 10 11 12 15 IRQ X
JP5
3 4 5 7 9 10 11 12 15
IRQ
X
Figure 2.6 Default Interrupt Setting
2.9 Timer & Event Interrupt Setting
The PET-48DIO has an interval timer/counter 8253 on board. It offers
3 independent 16-bit programmable down counters; counter 1 and
counter 2 are cascaded together for timer pacer trigger. and counter 0
is for event counting. Figure 2.7 shows the 8253 timer / counter
connection.