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Signal Connection and Applications
4.3
Timer / Counter Connection
The PCI-8554 has four 8254 chips on board. It can offer 10
independent 16-bit programmable down counters and cascaded
counters. To implement your application, you can following the
procedure to design your application and connect the signals.
1.
Check if use a clock source with fixed frequency, if answer is
‘No’, external clock source must be used and go to step 3.
2.
Calculate the frequency
of clock according to your application
and
decide the clock source:
internal, external, or cascaded,
then decide which counter is used.
3.
If external clock source is used, generate a clock source
outside the board and check the frequency. If external clock
source is used, you have to decide whether debounce function
is used or not, and then set the jumper JP1 ~ JP10.
4.
Decide the gate control source:
always enable or externally
control,
if gate control is necessary, connect the gate signal
5.
Program the counter / timer using desired mode.
Содержание PCI-8554
Страница 1: ...NuDAQ PCI 8554 Multi functions Counter Timer Card User s Guide Recycled Paper...
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Страница 11: ...Introduction 3 The second interrupt source comes from external source 100 pin SCSI II female connector PCI Bus...
Страница 13: ...Introduction 5 Humidity 5 95 non condensing Power Consumption 5 V 350 mA typical Dimension 134mm L X 107mm W...
