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Altera_Forum's avatar
Altera_Forum
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14 years ago

TSE, nichestack tx from fixed location

i am using a design example where the tx sgdma is getting its data from an sdram. i start it all with the sendto() function. problem is the data i want to send comes from a fifo, and so it seems a detour putting it in the sdram and sending from there.

is there any easy way to make the tx sgdma fetch data directly from the fifo? in sopc builder i can connect it the way i want, but is fetching from the same location like this possible with the nichestack?

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Thanks, i will. but thats not what i meant. I want to use the DMA, only instead of making it get data from a memory, i would like it to read from a fixed location. more spesific a onchip fifo. is this possible?

    --- Quote Start ---

    You can send directly data to the MAC without going through the DMA, but then you need to bypass the nichestack and generate all the Ethernet packet in hardware.

    Have a look at the nios ii udp offload example (http://www.alterawiki.com/wiki/nios_ii_udp_offload_example).

    --- Quote End ---

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Yes it is possible but in that case you need to bypass the Interniche stack and directly setup and use the SGDMA from your code.

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    I see. the stack is very useful so i dont want to bypass it entirely, I hoped it could be done with minor modifications to the stack.

    thought will be removed =)

    thanks