Using Input Points for Triggering Acquisition
Hardware input points located on the DIO board may be specified in the Visionscape Acquire Step to trigger acquisition. Acquisition can be specified on either the leading edge or trailing edge of a pulse. If the Visionscape PCIe IO boards are used in this manner the following procedure must be observed.
- If leading (low-to-high, rising) edge triggering is specified the trigger signal must be wired to one of the lower 8 input points (I-00 to I07) in the diagram above - IN0 to IN7 in Visionscape
- If trailing (high-to-low, falling) edge triggering is specified the trigger signal must be wired to one of the upper 8 input points (I-10 to I-17) in the diagram above - IN8 to IN15 in Visionscape.
This constraint is only applicable to Input points used as triggers in the Acquire or the Digital Input Step. The Digital Input Step will report the state of all 16 inputs at the time that it is called if no Data Valid signal is assigned.