NPM PPCI7443, Руководство пользователя

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Operation Theorem
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4.7 Position compare and Latch
The PPCI7443 provides position compare function in axis 0 and 1,and
position latch function in axis 2 and 3. The compare function is to “output a
trigger pulse when counter reached the value set by user”. CMP1 (Axis0)
and CMP2 (Axis 1) are used for compare trigger. The latch function is to
capture values of all 4 counters (refer to section 4.4) at that instant latch
signal activate. LTC3 (Axis 2) and LTC4 (Axis 3) are used to receive latch
pulse.
4.7.1 Comparators of PPCI7443
There are 5 comparators in every axis of PPCI7443. Each comparator gets
its unique functionality. Here is the table of description:
Note: Not all the 5 comparator get the ability to trigger output pulse via CMP.
It is only the comparator 5.
The compare 1 & 2 are for soft limit, please refer to section 4.9. The
comparator 3 is used to compare with position error counter. It is very useful
for detecting if a stepping motor lost pulses. To enable/disable the step-
losing
detection and set the allowed tolerance:
_7443_set_error_counter_check()
The PPCI7443 will generate an interrupt if step-losing is enabled and
occurred.
The comparator 4 is a general-purposed comparator, which will generate
interrupt (default reaction) if the comparing condition comes into existence.
The comparing source counter can be any counter. The compared value,
source counter, comparing method and reaction are set by software
function call
_7443_set_general_comparator()
.
Compare Source Description Function Related
Comparator 1 Command
position counter
Soft Limit (+)
(Refer to section
4.9)
Comparator 2 Command
position counter
Soft Limit (-)
(Refer to section
4.9)
_7443_set_softlimit
_7443_enable_softlimit
_7443_diable_softlimit
Comparator 3 Position error
counter
Step-losing
detection _7443_error_counter_check
Comparator 4 Any counters General- purposed _7443_set_general_comparator
Comparator 5
(Only Axis 0
& 1) Feedback position
counter Position compare
function (Trigger)
_7443_set_trigger_comparator
_7443_build_compare_function
_7443_build_compare_table
_7443_set_auto_compare