NuDAQ ACL-8112 Series, Руководство пользователя

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Installation
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2.9 Clock Source Setting
The 8254 programmable interval timer is used in the ACL-8112. It
provides 3 independent 16-bit programmable down counters. The input
of counter 2 is connected to a precision 2MHz oscillator for internal pacer.
The input of counter 1 is cascaded from the output of counter 2. The
channel 0 is free for user's applications. There are two selections for the
clock source of channel 0: the internal 2MHz clock or the external clock
signal from connector CN3 pin 37. The setting of clock is shown as
Figure 2.6.
2.10 IRQ Level Setting
The ACL-8112 can connect to any one of the interrupt lines of the PC I/O
channel. The interrupt line is selected by the jumper JP5 of ACL-
8112DG/HG or JP3 of ACL-8112PG. If you wish to use the interrupt
capability of ACL-8112, 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 2.7 shows the default
interrupt jumper setting IRQ5. You only remove the jumper from IRQ5 to
other new 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 :
IRQ15
(default setting)
JP5 / JP3
5 6 7 9 10 11 12 15 X
IRQ
3
JP5 / JP3
5 6 7 9 10 11 12 15 X
IRQ
3
Figure 2.7 IRQ Level Setting