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CPLD and SDRAM

Altera_Forum
Honored Contributor II
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Hello 

Is that the CPLD has enough resources to be able to control a SDRAM  

Thanks
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Altera_Forum
Honored Contributor II
737 Views

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
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Altera_Forum
Honored Contributor II
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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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Altera_Forum
Honored Contributor II
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--- Quote Start ---  

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 

--- Quote End ---  

 

 

 

thank you for this answer 

:) :)
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Altera_Forum
Honored Contributor II
737 Views

Hello 

 

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

 

Thank you  

Alex :)
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Altera_Forum
Honored Contributor II
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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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Altera_Forum
Honored Contributor II
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--- Quote Start ---  

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 

--- Quote End ---  

 

 

 

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
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Altera_Forum
Honored Contributor II
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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
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