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Altera_Forum's avatar
Altera_Forum
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18 years ago

TSE MAC and Marvell 88E1111

I'm having trouble to bring up the TSE MAC to Ethernet interface on the Stratix II GX PCIe board. I was able to instantiate a triple speed Ethernet MAC and build logic around it. The loopback at the ...
Altera_Forum's avatar
Altera_Forum
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16 years ago

Try to use a separate descriptor for the "next" argument in alt_avalon_sgdma_construct_mem_to_stream_desc.

Maybe something like 
        alt_avalon_sgdma_construct_mem_to_stream_desc(
           (alt_sgdma_descriptor *) desc, // descriptor I want to work with
           ((alt_sgdma_descriptor *) desc)+1,// pointer to "next"
           (alt_u32 *)ActualData,               // starting read address
           (length),                                  //#  bytes
           1,                                        // don't read from constant address
           1,                                        // generate sop
           1,                                        // generate endofpacket signal
           0);                                       // atlantic channel (don't know/don't care: set to 0)
I'm not sure about what happens if you make the descriptor point to itself as "next".

If that's not it, I don't have any other idea... I never had this problem with the SGDMA.