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Altera_Forum
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15 years ago

Error: Can't place differential I/O negative pin mem_dqs[0] at a differential I/O pos

When I compile my own DDR3 ctrl, the errors show like below: error: can't place differential i/o negative pin mem_dqs[0] at a differential i/o positive location d29(pad_1046) error: can't place ...
Altera_Forum's avatar
Altera_Forum
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13 years ago

I experienced similar problem... by tracking back to the design files, look into where the OBAR, IBAR, and IOBAR (negative ports) helped me find out where the tool pick up the wrong polarity.