Altera DE2-115 - Page 34

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Figure 4-6 Connections between the push-button and Cyclone IV E FPGA
Pushbutton releasedPushbutton depressed
Before
Debouncing
Schmitt Trigger
Debounced
Figure 4-7 Switch debouncing
There are also 18 slide switches on the DE2-115 board (See Figure 4-8). These switches are not
debounced, and are assumed for use as level-sensitive data inputs to a circuit. Each switch is
connected directly to a pin on the Cyclone IV E FPGA. When the switch is in the DOWN position
(closest to the edge of the board), it provides a low logic level to the FPGA, and when the switch is
in the UP position it provides a high logic level.