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Searching example code or manual entry regarding ACP mapping for EMAC DMA access

Honored Contributor I



we are using a Cyclone V SOC and its integrated EMAC for a high bandwidth application. 



  • All communication to the device are based on gigabit ethernet. 

  • The mass-data are processed mostly by FPGA hardware 

  • The control channel is done by SW 



The EMAC should now 



  • Send mass-data from one part of the DDR3 without usage of the l2 cache 

  • ​... so the bandwidth of the cache isn't affected by this 

  • Send sw generated control packets from the other part of the DDR3 with the usage of the l2 cache 

  • ... so our IP-Stack can stay unaware about caching effects etc. 



We thought, this should be possible using a well-tailored ACP window so the EMAC can differentiate between the two DDR3 locations. 


For now, we have only found the register description (starting at page 600).and would be happy to find a more step-by-step description ... ACP for Dummies ... more or less. 


=> Is there an easy way to get a system running without too much headaches? 

.... I'm doing direct register writes quite often (coming from the FPGA-side) - I would just like to exploit any possibilities for a more high-level-approach ;-) 


Best regards, 



PS: I didn't find a subforum where the question might have fitted any better but please move me away if you like to
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Honored Contributor I

I've found an interesting article of one of Altera's employees (Nick Ni) 

describing a reference design that would make use of the ACP functionalities 

but no information, if this design might be available for testing  

or - in my case - to get a grasp of what is needed: