Measurement Computing ADAC-LVi - Manual (Page 83)

Chapter 2 Digital I/O VIs
ADAC LabVIEW VI 77
Digital I/O Examples
Examples for each Easy Digital Input VIs are provided, and located in the ADAC
Examples in your LabVIEW directory. Example programs all provide a dialog box
allowing the selection of any ADAC board installed in ADAC-LVi. If a board incapable
of performing a particular example is selected, an error will occur indicating non-support.
The Easy DIO Read Port example demonstrates the use of ADAC Read from Digital
Port VI. The example continuously reads a digital port in loop until the EXIT button is
pressed.
The Easy DIO Write Port example demonstrates the use of ADAC Read from Digital
Port VI. This VI writes the specified binary value to a single digital output port when the
UPDATE button is pressed.
The Advanced 5600DIO Acq Port example demonstrates the use of the 5600 Series
PORT STRUCT. This VI shows how to use the 5600 Series PORT STRUCT. It uses the
5600 board’s interrupt capabilities to catch digital input lines changing state on each of
the 16 digital input lines.
An occurrence is used for a continuous asynchronous acquisition. This is a non-timed
acquisition, meaning that no clocking is used to control the acquisition rate. It is also a
continuous circular buffered acquisition. This means that a software buffer is used
between your DAQ board and LabVIEW. While data is being transferred from your
board into one of the input buffers, LabVIEW is reading data from another buffer. The
occurrence VI makes the acquisition asynchronous (allowing processor time for other
things to run) by causing the loop to sleep until notified a buffer is available which is then
read into LabVIEW.