Altera Corporation
Reference Manual
2–21
May 2006
Stratix II GX EP2SGX90 Transceiver Signal Integrity Development Board
Board Components & Interfaces
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Board references S1 through S6 are push-button switches allowing
general user I/O interfaces to the Stratix II GX device.
S1-S6 are user-defined, momentary-contact push-button switches used to
provide stimulus to a user design on the board. Each push-button is
connected through debounce circuitry to a Stratix II GX general-purpose
I/O pin as listed in
. When the switch is pressed and held
down, the device pin is set to logic
0
, when the switch is released, the
device pin is set to logic
1
.
The push button device is a small form factor switch similar to the
Panasonic Tactile Switches (EVQPAC07K).
provides
operational descriptions and schematic signal names.
Table 2–13. Push-Button Switches (S1 Through S6)
Push-Button
Name
Board
Reference
Designator
Schematic Signal
Name
Stratix II GX Device
(U20) Pin Number
PB0
S1
PB0_IN
AD28
PB1
S2
PB1_IN
AF34
PB2
S3
PB2_IN
AF33
PB3
S4
PB3_IN
AF30
PB4
S5
PB4_IN
AF29
(1)
The PB5 is a special purpose button, called
DEV_CLRn
, connected to the
AH20
pin
of the FPGA. The PB5 clears the FPGA data.