NPM PPCI7443, User Manual

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Operation Theorem
1,2 or 4. 4x AB phase mode is the most commonly used for incremental
encoder input. For example, if a rotary encoder has 2000 pulses per phase
(A or B phase), then the value read from the counter will be 8000 pulses per
turn or –8000 pulses per turn depends on its turning direction. These input
modes can be selected by _7443_
set_pls_iptmode() function.
In case that some applications don’t implement an encoder, it is possible to
set the feedback counter source to be the output pulse, just as the
command counter. Thus, the feedback counter and the command counter
will actually have the same value. To enable the counters counting pulses
input from pulse output, set “S
rc” parameter of software function
_
7443_set_feedback_src() to “1”.
Plus and Minus Pulses Input Mode(CW/CCW Mode)
The pattern of pulses in this mode is the same as Dual Pulse Output Mode
in Pulse Command Output section, expect that the input pins are EA and
EB.
In this mode, pulse from EA causes the counter to count up, whereas EB
caused the counter to count down.
90
rrrr
phase difference signals Input Mode(AB phase Mode)
In this mode, the EA signal is 90
r
phase leading or lagging in comparison
with EB signal. Where “lead” or “lag’ of phase difference between two
signals is caused by the turning direction of motors. The up/down counter
counts up when the phase of EA signal leads the phase of EB signal.
The following diagram shows the waveform.
The index inputs (EZ) signals of the encoders are used as the “ZERO”
index. This signal is common on most of the rotational motors. EZ can be
used to define the absolute position of the mechanism.
The input logic
polarity of the EZ signals is programmable by software function
_7443_ set_home_config(). The EZ signals status of the four axis can be
monitored by get_io_status().
EA
EB
Negative Direction
EA
EB
Positive Direction