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You can use the VI key events, the PDA Button Input VIs, or a combination of both to detect user key inputs.

Using VI Events

Use the Key Down and Key Up VI events with an Event structure for event-driven key detection. The VI key events do not override the OS mapping of the application keys, which are the hardware keys that are mapped to specific applications; for example a calendar application.

The Key Down and Key Up VI events do not generate events if any of the front panel controls have focus, including controls that do not visually indicate when they have focus, such as Boolean controls and increment and decrement arrows. You must tap an empty portion of the PDA screen to remove focus from a control.

Using the PDA Button Input VIs

You can use the PDA Button Input VIs to read the state of the buttons on a PDA device. Use the Get PDA Button Input VI to poll for a change of button state. The PDA Button Input VIs might not detect all buttons because PDA device hardware buttons are device-specific.

The PDA Button Input VIs use the Microsoft Windows Powered Pocket PC Game API (GAPI). GAPI keys include a limited number of keys, but the PDA Button Input VIs detect the key inputs regardless of front panel focus or the mapping of the application keys.

Using a Combination of VI Events and PDA Button Input VIs

You also can use a combination of VI events and PDA Button Input VIs to detect key input on PDA devices. Use the Initialize PDA Button VI and the Close PDA Button Reference VI to suspend the OS application key mapping while the PDA application has focus, which results in the PDA application detecting the key events that are not detected if you use only key events.