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Chaining DMA

Altera_Forum
Honored Contributor II
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Hi, 

 

I want to reuse the chaining DMA example. I build a simulation environment for System to Endpoint data transfer using 3 descriptors, 256Bytes in each descriptor. I found a suspicious behaviour of chaining DMA. The programming sequence of DMA is: 

 

BAR2 0x10 = 32'h3 

BAR2 0x14 = 32'h0 

BAR2 0x18 = 32'h00_01_00_00 

BAR2 0x1C = 32'h2 

 

@ Rootport I received a read request of 4*3 DWORDs @ address 0x00_01_00_10. This is strange. I supposed the address should be the base address of Descriptor table (32'h00_01_00_00) that I programmed @ BAR2 0X18. 

 

Thanks 

Ali Umair
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