ADLINK Technology PCI-8136, Руководство пользователя

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32 Operation Theory
4.4 Pulse Input and Position Compare
4.4.1 Pulse Input
The PCI-8136 has 6 32-bit pulse input channels for encoder
counter. It can accept 3 kinds of pulse signal:
1. Plus and minus pulse inputs (CW/CCW mode)
2. 90°phase difference signals(AB phase mode)
3. Pulse and direction inputs (Pulse/DIR).
90° phase difference signals may be selected to be multiplied by a
factor of 1, 2, or 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 These input modes can be
selected by software function calls.
Plus and minus pulses input mode(CW/CCW Mode)
In this mode, pulse from EA causes the counter to count up,
whereas EB causes the counter to count down.