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Altera_Forum
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16 years ago

Weird heap access in NIOS w/DDR2 memory

Guys, I have a very strange behavior of my system. I’m very close to get crazy, because I don’t find the reason now for 2 days. Well, the situation is: Altera C3120 dev. board. Bottom DDR2...
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Altera_Forum
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16 years ago

Thank you guys! You were trying to be helpfull, but it seems the case was a bit different. By accident I could find the problem, the solution is a bit strange:

So this is a 3C120 dev kit, one AC-DC PS is bundled with it. Replacing this original adaptor solved the problem. The original one got faulty and sourced only 8 Volts. This caused that the board was working perfectly - it looked like to do - misleading me. Only when I wanted to use the DDR2 I got problem.

However this is interesting. This board uses Linear Technology stabilizers. So how is possible that if a part needs max 3.3 Volt (DDR2 1.8 Volt) it cannot work if the stab IC gets "only" 8 Volt??? If I design something, I try to have the lowest source voltage as possible. In such case for example I would source max. 5 volt. Agree?

Thanks again!