CPLD and SDRAM

Hello

I want to interface and monitoring a SDRAM with a CPLD (Max II altera), so is that the CPLD has enough resources to be able to monitoring a SDRAM.

Note:it is not an IP (SDRAM) that I want to create

Thanks

Hi!

A CPLD should work nicely if you want to just turn that into an SDRAM controller. A MaxII with 240LE's should be ample to get that going. The problem you might have is that a) AFAIK the MaxII doesn't have a PLL, which means you'll have to use a clock that's fast enough (you didn't specify how fast it needs to be, so this might not be an issue) and b) you'll need a boatload of pins.

I'm about to embark on the same journey.. Good luck!

-Mux

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Hi!

A CPLD should work nicely if you want to just turn that into an SDRAM controller. A MaxII with 240LE's should be ample to get that going. The problem you might have is that a) AFAIK the MaxII doesn't have a PLL, which means you'll have to use a clock that's fast enough (you didn't specify how fast it needs to be, so this might not be an issue) and b) you'll need a boatload of pins.

I'm about to embark on the same journey.. Good luck!

-Mux

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thank you for this answer

:) :)

Hello

I will use a 48Mhz clock, do you think that is enough!?

Thank you

Alex :)

That depends on the amount of time you need for refresh. Generally you need to refresh every row with 64ms or thereabouts, depending on the size. Which SDRAM are you using?

-Mux

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That depends on the amount of time you need for refresh. Generally you need to refresh every row with 64ms or thereabouts, depending on the size. Which SDRAM are you using?

-Mux

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Hello

I use this SDRAM : IS42S16160D-7TL 256M(16Mx16).

Do you know how to calculate the time required to unload the data (256 Mbites) of the SDRAM to the CPLD.

Thank you

Hi!

Erm, have a look at the datasheet and figure out the timing / clocks based on the clock-speed you've selected. SDRAM is a lot different from SRAM. The datasheet should have about 60 pages worth outlining the states / transitions. Not exactly sure what you mean by unloading the data..

Hope this helps,

-Mux