HI! all. As we know, we always use the Xlnk class to apply for memory allocation before using DMA, but in this case, the physical address obtained through input_buffer.physical_address is beyond our control. I want to know whether the physical address can be assigned by ourselves when PYNQ applies…

The physical addresses are entirely at the whim of the Linux kernel so there’s no way to specify the address for buffers in system DRAM. Is there a reason you need to? Peter

Hi! Peter, Thanks again for your reply！I want to use two DMAs and two HP ports to transfer data from DRAM to PL at the same time, just like the link: Multiple DMAs, But only one work . However, I found that one of the DMAs was not working properly. Then, I read the status register and found that it …

We don’t support accessing the system DRAM at a non-zero offset. Is there a reason that you need to do this? Vivado is generally happier if everything’s at the same offset as well. If you really want to you could add your offset to the buffer’s device_address property which would give you the behav…

Ok, thank you, Piter. I am a newbie, so I want to know if the block design can be designed like this [1]

That looks fine - the default addresses allocated by the address editor for this design should also be fine with PYNQ - namely the DDR memory at offset 0 on both HP0 and HP1. As you come to optimise the design you might want to consider HP2 instead of HP1 as HP0 and HP1 share the same port on the D…

Thank you very much for your patience in explaining the things to me.

How to specify the allocated memory address in PYNQ

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How to specify the allocated memory address in PYNQ

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