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Altera_Forum's avatar
Altera_Forum
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20 years ago

SDRAM does not retain data

I have a custom board with an altera EP1C12, a flash memory and a MT48LC4M32B2 SDRAM memory. Timings I set in SOPC builder are the default timings for this part. When I set the value 0x00000000 ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
20 years ago

Sounds like a hardware issue, to me. In fact, it sounds (to me) like your memory is somehow expecting the controller to refresh it.... The Altera-provided controller, for SDRAMs, only supports auto-refresh memories and configures these memories to go into auto-refresh mode during initialization.

I would say that you have some sort of initialization issue, or, perhaps, a bad SDRAM. Continuing with a pure SW debug is a dead-end.

Best of luck!

- slacker