ADLINK Technology PCI-8366+, User Manual

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110 Operation Theory
sider the continuous compared with triggering pulse output
feature.
Figure 4-40: Trigger Output
SSCNET motion board has a compare mechanism of each axis
that is operated by DSP. DSP will compare the receiving counter
with users’ desired value and do the actions in one SSCNET cycle
if the position is achieved. Besides, we provide triggering pulse
output when the compare condition happens. The triggering pulse
is performed by DO channel. It will output a specific pulse width
when compare condition happens.
First, users must set one of the digital output channels as one
comparator’s triggering output. Map more than one comparators
to single digital output channel is not allowed, but reverse case is
allowed.
Second, users must build up an array that contains the table of
compare points. You can assign a region by giving start and end
index of this array for the table of compare points.
Third, users must assign the compare direction of the table. It is
useful because users needn’t rebuild the table reversely again if
they want to do a reverse comparasion.
The triggering pulse is as below. The pulse width is about 1ms
which is decided by SSCNET cycle time. Our suggestion trigger-
ing frequency is less than 500Hz.