 | Read/Write (NI-IMAQ I/O) FAQs |
Q: How can I access digital input results?
The Read/Write (NI-IMAQ I/O) step logs selected measurements when the step is executed. You can access the measurement results by using a subsequent step that can access measurement results. Examples of steps that can use measurement results are, but not limited to, the Modbus Slave, Serial I/O, TCP I/O, Run LabVIEW VI, Calculator, Logic Calculator, and Custom Overlay steps.
Q: When does the edge detection input get reset?
When a digital input line is configured for edge detection, the specified line is continuously monitored until a change is detected that lasts longer than the filter width. When a change is detected, the digital input line reports the change the next time the Read/Write (NI-IMAQ I/O) step is executed. Performing additional reads on the digital input line using other Read/Write (NI-IMAQ I/O) steps does not interfere with the edge detection unless the other Read/Write (NI-IMAQ I/O) steps reconfigure the line to detect a different type of edge. It is not recommended to have multiple Read/Write (NI-IMAQ I/O) steps using the same digital input for different types of edge detection.
Q: When a digital output line writes a system signal, when is the line updated?
When a system signal is associated with a digital output line, the digital output line is updated whenever the system signal changes. Once a digital output line is associated with a system signal, the line always outputs the current state of the system signal. You can reassign the source for a digital output line using another Read/Write (NI-IMAQ I/O) step. All other reads and writes occur when the step executes. It is recommended to use an Read/Write (NI-IMAQ I/O) step in the Setup state for system signal output because once the step is called the configured digital output line updates the system signal while the main inspection runs.