DE10-Lite
User Manual
25
www.terasic.com
May 11, 2018
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◼
User-Defined Push-buttons
The board includes two user defined push-buttons that allow users to interact with the MAX 10
FPGA device. Each of these switches is debounced using a Schmitt Trigger circuit as indicated in
Figure 3-13
. A Schmitt trigger feature introduces hysteresis to the input signal for improved noise
immunity, especially for signal with slow edge rate and act as switch debounce in
Figure 3-14
for
the push-buttons connected.
Table 3-3
list the pin assignment of user push-buttons.
Figure 3-13 Connections between the push-button and MAX 10 FPGA
Figure 3-14 Switch debouncing
Table 3-3
Pin Assignment of Push-buttons
Signal Name
FPGA Pin No.
Description
I/O Standard
KEY0
PIN_B8
Push-button[0]
3.3 V SCHMITT TRIGGER"
KEY1
PIN_A7
Push-button[1]
3.3 V SCHMITT TRIGGER"
Pushbutton released
Pushbutton depressed
Before
Debouncing
Schmitt Trigger
Debounced
