ADLINK Technology PCI-8132, Руководство пользователя

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Operation Theorem
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It can accept 2 kinds of pulse input.: (1). plus and minus pulses
input(CW/CCW mode); (2). 90
°
phase difference signals(AB phase
mode). 90
°
phase difference signals may be selected to be multiplied by
a factor of 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
_8132_set_pls_iptmode() function.
To enable the counters counting pulses input from (EA, EB) pins, set
“
cnt_src ” parameter of software function _8132_set_cnt_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
°
phase difference signals Input Mode(AB phase Mode)
In this mode, the EA signal is 90
°
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.
EA
EB
Negative Direction
EA
EB
Positive Direction