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Altera_Forum
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13 years ago

Modular SGDMA - Doubt on Target Address

I am using the "ALT_PCIE_QSYS_SIMPLE" sample application. The code is executed successfully. It had leaded me to the following doubts: --------- Doubt 1 --------- By default, the targe...
Altera_Forum's avatar
Altera_Forum
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13 years ago

The mSGDMA masters are probably only setup to handle 1MB worth of data in that example. If you increase the payload size you'll have to change the master settings to handle that.

That said.... if you are sending more than 1MB of data over PCIe, just use more descriptors. It's a scatter-gather DMA so it's meant to handle multiple back to back transfers. Increasing the payload size that the masters can handle is going to drop your Fmax of your design so you are better off just using multiple descriptors.