Programmable Devices
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Hard Memory controller vs Soft Memory Controller

Altera_Forum
Honored Contributor II
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Hi, 

I'm a newbie here. Sorry for this stupid question. 

I would like to know what is the difference between hard and soft memory controller. How can I identify which one i'm using? 

 

Regards
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Altera_Forum
Honored Contributor II
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A hard memory controller will use the hard macros on the chip, so it will use hardly any logic, leaving it all for your own design. A Soft one will only use logic. 

 

The hard macros can usually be clocked faster.
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Altera_Forum
Honored Contributor II
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The 28nm FPGAs all have dedicated logic for memory controllers, so even a "soft" implementation will use some special hardware. But ArriaV/CycloneV have a truly hard implementation too(it's not just a few IO structures like the DLL -> DQS strobe, but the whole controller is hardened). I'm sure the fit reports say something about it, but haven't looked. In the MegaWizard for these devices there is a checkbox on the front page that says whether it's hard or soft. The hardened one saves resources(since you won't use that logic for anything else) and it's very good as a multi-port memory controller. (Not that you can't create a multi-port with a soft controller, it's just more logic, naturally). The device handbook should talk about the hardened one.

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