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Altera_Forum
Honored Contributor
18 years agoProblems about DDR2!
Error: Too many output and bidirectional pins in I/O bank 3 assigned near VREF pin AB11 (VREFGROUP_B3_N1) on device EP3C120F780C7 -- no more than 9 output and bidirectional pins allowed near the VREF...
Altera_Forum
Honored Contributor
18 years agoI have already read the datasheet you said for several times, but I am confused. I only konw the meaning of the "Vref group", but what is the exact meaning of the "VCCIO group"? Does it mean different I/O pins are associated with different VCCIO?