Position Counter Value Capture (Latch). ADLINK Technology PCI-8136M

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

EA

EB

Negative Direction pulse and direction input(Pulse/DIR)

In this mode, the high / low status of EB decides the counter value to increase or decrease (Direction), whereas EA decide the count number (Pulse).

EA

EB

Negative Direction

4.4.2 Position Counter Value Capture (Latch)

The EZ (index signal) of each pulse input channel doesn't affect counter value. It can capture (latch) current counter value by proper setting, and generates an interrupt signal when receiving a rising edge. The counter value capture function is very useful to sensing position of a moving object.

Related functions:

_8136_P_Initial() : please refer to section 5.2 _8136_P_Set_Input_Type(),

_8136_P_Read(), _8136_P_Clear(), _8136_P_Set_Index_Latch(),

_8136_P_Read_Index(), _8136_P_Read_Latch_Value(): please refer to section 5.8

Operation Theorem

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