Capture is used to copy the current value of the up/down counting register to a capture register. It therefore fixes the immediate value at the precise moment the operation started.
Capture is only possible in combined up/down counting mode (all modules).
Capture done CAPT_DONE information (%Ir.m.c.2) is an event which can undergo an event processing operation.
The operation is triggered:
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either directly, via the software: Direct capture DIR_CAPT command (Qr.m.c.2),
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or by the hardware: when the ICapt ST_CAPT (%IWr.m.c.2.4) physical input status has changed, with pre-enabled software (Capture enable DIR_ENAB (%Qr.m.c.0) command). This signal can be:
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the rising edge of ICapt input,
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the falling edge of ICapt input,
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The rising edges and the falling edges of ICapt input (TSX CTY 2C only).
NOTE: time performances are at a maximum when ICapt input is configured on the rising or falling edge.
Function hardware structure
The figure below shows the hardware structure of the capture function. The associated language objects are described in the
default objects section.
The time diagram below shows the capture mode on the rising edge of ICapt. The other modes (capture on falling edge, on rising and falling edges) are similar.
