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Altera_Forum
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14 years ago

PCIe BAR size must be larger than Avalon size

I'm using PCIe hard ip with SOPC builder with an Avalon MM conduit to my slave application logic. The size of the memory map on the conduit is 2M so I set my Avalon size in SOPC to 2 pages at 1M each...
Altera_Forum's avatar
Altera_Forum
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14 years ago

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My local bus width is 21 bits, but the BAR space automatically gets set to 23 bits.

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Are your sure that your custom slave component has a memory size of 2MByte ? Can you check that in the SOPC Builder ? A local bus width of 21 bits (I suppose address bus width) does not neccessarily mean 2 MByte address size. The avalon slave address is not a byte address, it is a slave data width address. If your slave has a datawidth of 32 bits then the address is a dword address. A 21 bit dword address corresponds to a 23 bit byte address.