Altera Cyclone III FPGA Starter Board - Manual (Page 19)

Altera Corporation 2–11
April 2012 Cyclone III FPGA Starter Board Reference Manual
Board Components and Interfaces
Push-Buttons
The board has system reset, user reset, and user push-buttons. Table 2–9
lists the pinout for all push-buttons. The push-buttons are in logic “1”
until depressed.
Figure 2–5 shows the push-buttons.
Figure 2–5. Push-Buttons
System Reset Push-Buttons
The system reset push-button starts a reconfiguration of the FPGA from
flash memory.
User Reset Push-Buttons
The user reset push-button is an input to the Cyclone III device. This
push-button is intended to be the master reset signal for the FPGA
designs loaded into the Cyclone III device. The user reset push-button is
connected to the DEV_CLRn pin on the FPGA. The DEV_CLRn setting is a
pin option in the Quartus II software that you must enable to function as
DEV_CLRn
instead of a standard I/O.
Table 2–9. Push-Button Pinout
Signal Name FPGA Pin Direction Type
KEY0 F1 Input 2.5 V
KEY1 F2 Input 2.5 V
KEY2 A10 Input 2.5 V
KEY3 B10 Input 2.5 V
CPU_RESET_N N2 Input 2.5 V
RECONFIGURE H5 (nConfig) Input 2.5 V