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TSE, nichestack tx from fixed location

Altera_Forum
Honored Contributor II
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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?
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Altera_Forum
Honored Contributor II
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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).
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Altera_Forum
Honored Contributor II
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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 ---  

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Altera_Forum
Honored Contributor II
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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.

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Altera_Forum
Honored Contributor II
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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
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