Altera Cyclone II FPGA Starter Development Board User Manual download pdf (Page 34)

2–16 Reference Manual Altera Corporation

Cyclone II FPGA Starter Development Board October 2006

Development Board Components

Additionally, with the switch in the RUN position, the Quartus II

Programmer can program the FPGA directly through the USB Blaster

circuit. With the switch in the PROG position, the Quartus II Programmer

can program the EPCS4 device.

Push Button Switches

The development board provides four push button switches,

KEY0-KEY3, located at the bottom right on the development board below

the green LEDs, LEDG0-LEDG7 (Figure 2–10). The momentary-contact

switches provide stimulus to designs in the FPGA.

Figure 2–10. Push Button Switches and Green LEDs

A switch generates an active-LOW pulse at 0 volts when pressed,

returning to a HIGH logic level at 3.3 volts when released. A Schmitt

Trigger circuit on each switch debounces the signal (Figure 2–11).

Figure 2–11. Switch Debouncing

1 2 ... 29 30 31 32 33 34 35 36 37 38 39 ... 55 56

No comments

Altera Cyclone II FPGA Starter Development Board User Manual Page 34