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Last time before I used CIVGX board, I tested and run the same design on CIII Starter board too. Through the HSMC, I give 3.3V input signal and it is still functioning well. So I have no idea why it is not functioning in CIVGX.
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Sorry to be blunt but I don't care what you escaped without destroying before you broke the CIVGX.
The Cyclone IV data sheet in I/O Stardard Specifications, Table 1-15 in the version I have, says VinHigh Max for a 2.5V IO is Vcc+0.3V, ie 2.8V.
If you're driving anything higher in you're asking for trouble (unless you add properly calculated current limiting resistors).
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Also, I find the MAXII device does not connect to HSMC pins. Attached the MAXII block diagram from the C4GX reference manual.
Pls advice if I understand the block diagram wrongly.
Thank you.
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There isn't enough detail in that to diagnose the problem, try to get hold of the schematics and trace all the HSMC connections.
Nial
Honored Contributor
