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Altera_Forum
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14 years ago

modifying pin assignments in Quartus II 10.1

Anyone know of the best way to change pin assignments in Quartus II 10.1? Tried in Pin Planner to change pin assignment locations for some signals. (1.) Tried just changing it to the des...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Hi,

Can anyone help me with this error in quartus?

I am using DDR2 memory with EP3C120F780C7

DDR2: U25 and U26 bottom chip

I think there is some problem with the pin assignment order to the memory pins.I have assigned the pins as mentioned in the manual.

Error: Cannot place pin mem_dq[0] to location AG22

Error: Can't place VREF pin AC18 (VREFGROUP_B4_N1) for pin mem_dq[0] of type bi directional with SSTL-18 Class I I/O standard at location AG22

Error: Too many output and bidirectional pins per VCCIO and ground pair in I/O bank 4 when the VREF pin AC18 (VREFGROUP_B4_N1) is used on device EP3C120F780C7 -- no more than 9 output/bidirectional pins within 12 consecutive pads are allowed when the voltage reference pins are driving in, but there are potentially 10 pins driving out.

How to change the continuous assignment?