User manual

DE2 User Manual
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Figure 3.3. The DE2 Control Panel concept.
The DE2 Control Panel can be used to change the values displayed on 7-segment displays, light up
LEDs, talk to the PS/2 keyboard, read/write the SRAM, Flash Memory and SDRAM, load an image
pattern to display as VGA output, load music to the memory and play music via the audio DAC.
The feature of reading/writing a byte or an entire file from/to the Flash Memory allows the user to
develop multimedia applications (Flash Audio Player, Flash Picture Viewer) without worrying about
how to build a Flash Memory Programmer.
3.2 Controlling the LEDs, 7-Segment Displays and LCD Display
A simple function of the Control Panel is to allow setting the values displayed on LEDs, 7-segment
displays, and the LCD character display.
In the window shown in Figure 3.2, the values to be displayed by the 7-segment displays (which are
named HEX7-0) can be entered into the corresponding boxes and displayed by pressing the Set
button. A keyboard connected to the PS/2 port can be used to type text that will be displayed on the
LCD display.
Choosing the LED & LCD tab leads to the window in Figure 3.4. Here, you can turn the individual
LEDs on by selecting them and pressing the Set button. Text can be written to the LCD display by
typing it in the LCD box and pressing the corresponding Set button.
The ability to set arbitrary values into simple display devices is not needed in typical design
activities. However, it gives the user a simple mechanism for verifying that these devices are
functioning correctly in case a malfunction is suspected. Thus, it can be used for troubleshooting
purposes.