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Why should it damage the board?
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It will damage the FPGA on the board.
The FPGA is a Cyclone IV, which is
not 5v tolerant.
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On each GPIO are two different VCC's: VCC_SYS and VCC3P3. According to the user manual (
http://www.terasic.com.tw/cgi-bin/page/archive_download.pl?language=english&no=593&fid=75023fa36c9bf8639384f942e65a46f3) VCC_SYS is 5V and VCC3P3 is 3.3V. But I can't get voltages beyond 3.3V for the pins. So I need to change the voltage for the LCD to 3.3V and the voltage of the pins to 2.5V, right?
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p17 "DE0-Nano board provides two 40-pin expansion headers. Each header connects directly to 36 pins of the Cyclone IV E FPGA, and also provides DC +5V (VCC5), DC +3.3V (VCC33), and two GND pins"
Read the comment clearly: "connects directly to the FPGA pins".
You need to change the LCD to 3.3V, and leave the FPGA I/Os at 3.3V.
Cheers,
Dave
Honored Contributor
