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SGDMA in loop-mode

Altera_Forum
Honored Contributor II
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Hi all! 

I know that there are allready a lot of SGDMA-Threads posted in the forum, 

but it seems that I have a special problem regarding this IP. 

 

I like to use SGDMA in loop-mode, meaning that I have four descriptor-chains jumping from one to another and starting again with the first descriptor after the fourth by setting the PARK-bit. 

 

Everything works fine when I tell the SGDMA the exact amount of data to be transfered (Stream to Memory), but if I tell the SGDMA that every transfer should last until EOP is received, by setting length_or_eop to zero, the "TERMINATED_BY_EOP" error-bit is on in the descriptor status-byte after every transfer.  

 

Maybe Socrates had a similar Problem, when he posted that an error-bit got up, when he wanted to use the loop-mode, in the very interesting thread titled "SGDMA debug". 

 

So, does anybody know if this is a general problem of the SGDMA-core? 

Or is there anything else I could do? 

 

Thank you in advance for your help!
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Altera_Forum
Honored Contributor II
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O.K., I found another mistake in my Code which prompted the SGDMA to hang. 

 

It seems that it is normal, that the "TERMINATED_BY_EOP" error-bit is on after every transfer, when using the SGDMA transfering until EOP. 

 

It also seems that the error-bit has no effect on the DMA-process itself and can be ignored in this case.
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