NPM PPCI7443, Руководство пользователя

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Operation Theorem
4.7.2 Position compare
The position compare function is performed by the 5
th
comparator, whose
comparing source is the feedback position counter. Only the first 2 axes (0
and 1) can do position compare function. The position compare function is
to trigger a pulse output via CMP, when the comparing condition comes into
existence.
The comparing condition consists of 2 parts, the first is the value to be
compared, and the second is comparing mode. Comparing mode can be
“>“ , “=“ or “<“. The easiest way to use position comparison function is to
call the software function:
_7443_set_trigger_comparator(AxisNo, Method, Data)
The second parameter “Method” indicates the comparing method, while the
third “Data” is for value to be compared. In continuous comparing, this data
will be ignored automatically since the compare data will be build by other
functions.
Continuously compare
For user who wants to compare multiple data continuously, functions of
building comparison tables is also provided as shown in the following
1. _7443_build_comp_function(AxisNo, Start, End, Interval, device)
2. _7443_build_comp_table(AxisNo, tableArray, Size, device)
3. _7443_set_auto_compare(AxisNo, SelectSource)
Note: 1. Please turn off all interrupt function, when these function is
running
The first function is to build a compare list by start point, end point and
constant interval. The second is to build an arbitrary comparing table (data
array). The third function is a comparing source selection function. Please
put a value 1 in this parameter for using FIFO mode. Once it is set, the
compare machenism will start. Users can check current value which is
going to be compared by _7443_check_compare_data():