ICP DAS USA ECAT-2092T, Руководство пользователя

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7.2.2 Position Compare Trigger
The compare trigger function supports two modes: Single position compare and auto-
increment position compare.

Single position compare: The user has to set one compare position at which a digital
output signal will be triggered. The DO trigger will always be generate once the
encoder counter reaches this position, regardless from which direction. The compare
position can be altered by software at any time by following the procedure described
in the first column of Table 17.
 Auto-increment position compare: Here the compare position will automatically be
incremented by hardware once the current compare position has been reached. The
compare function will trigger a signal output and increment the compare position if
the current compare position has been approached from the configured direction. It
is important to reset the compare function by disabling/enabling it when the encoder
counter has been set to a different value by the user.
Process data required for doing position compare control: 0x16n0, 0x16n2, 0x1An0,
0x1An2 (n= 0;1). By using TwinCAT one of the predefined PDO Assignments which
contains the "Compare trigger" has to be selected.
The main variables of the process data objects 0x16n0 and 0x1An0 have already been
described in the previous section therefore only the compare position parameters will
be listed in the following tables.
0x16n2 (n= 0;1)
Parameter Object Description
Enable compare 0x70n2:01 The compare function will be activated if the "Enable
compare" parameter changes its value from FALSE to TRUE.
It is necessary to first set the following variables before
enabling the compare function:

"Set auto increment compare direction"

"Set first compare position"
 "Set auto increment compare value"
Once the compare function has been activated the "Enable
compare done" (0x60n0:08) value changes to TRUE.
If the encoder counter (0x60n0:11) has been reset or
assigned a new value then the compare function needs to
be reset by assigning FALSE/TRUE to the "Enable compare"
variable.
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