Psion Teklogix OMNii HDK XT10, User Manual

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Chapter 10: HDK Demo Application
Main Tabs
154 Psion Teklogix Omnii HDK User Manual
10.6.2.3 GPIO
The GPIO tab provides some screen elements to detect input and output activity on certain GPIO
lines of an expansion port.
• GPIO O/p [0/1/2] – Tapping these output buttons toggles activity on GPIO line 0, 1 and 2.
When a line is active, the corresponding “On/Off” button will be highlighted in green.
The corresponding LED on the breakout board (DS3, DS4 or DS5) also illuminates to
indicate activity.
• GPIO I/p [4/5/6] – These input indicators illuminate when activity is detected on GPIO line
4, 5, or 6. Activating the switch on the breakout board for the corresponding GPIO input
(SW5 DIP switch 1: line 4; SW5 DIP switch 2: line 5; SW3: line 6) introduces activity on the
line and illuminates the onscreen indicator.
• GPIO Interrupt 7 – This indicator illuminates to indicate activity on GPIO line 7. When this
occurs, activity is toggled on and off on GPIO line 3 for five seconds. Pressing switch SW4 on
the breakout board illuminates this indicator, and causes LED DS6 to flash for five seconds.
UART and GPIO devices share the same data pins on the expansion port, so the current function
of the pins must be defined by the application. If the UART tab was previously selected, the
following warning message will appear when selecting the GPIO tab:
Note: If the TestDriver.dll driver has not been loaded, the “GPIO Interrupt 7” indicator still
illuminates, but no activity occurs on GPIO line 3 and LED DS6 on the breakout board
does not flash.