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Altera_Forum
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15 years ago

PCIe polarity inversion Setting

I am using Altera PCIe x4 Soft IP 9.1 with a 2SGX60E device. As a result of the pcb layout, I have to reverse the polarity of the diffential pairs in both the receiver and the transmitter. To i...
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Altera_Forum
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15 years ago

There is an optional tx_invpolarity port in the alt2gxb megafunction, which is omitted in the pcie_serdes entity.

I just edited the pcie_serdes.vhd file and added the port to the alt2gxb component, then hardwired it to "1111" in the instantiation. I changed the "tx_allow_polarity_inversion" string to TRUE as well.

And there is no warning or error during synthesis.