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Altera_Forum
Honored Contributor
Honored ContributormSGDMA stride reads/writes
Has anyone used the Stride feature (available with the extended descriptor)? I using the Qsys PCIe example design on the wiki. When I enable the extended descriptor and stride option, the data tran...
Altera_ForumHonored Contributor
Honored ContributorHi BadOmen,
I have another question: I noticed that the Write-Masters do a Read-Ahead if my Fifos have data and there is no DMA-Transfer triggered. This is no Problem for me, but is there a way to read out the Fill-Level of the Internal Fifo in the Master? I was kind of confused when I wrote data to the Fifos and they suddenly disappeared (Fifo Fill-Level stayed 0). But a DMA-Transfer with the right size gave me the data. My problem is: I often don't know exactly how many data are received by the Fifos. If the disappear in the Write-Master I can only guess how many Bytes I have to transfer. I tried the Response Registers of the msgdma-Core with Low-Level access via "pci_debug-Tool" (Linux), but all I got was a complete System-Breakdown and no "Actual Bytes Transferred" or "Error". Can you help me?
