Critical Issue
This problem affects DDR3 products.
DDR3 memory interfaces with mem_ck
width greater
than one, targeting Arria V or Cyclone V devices, may encounter
a no-fit error similar to the following:
Error (175020): Illegal constraint of DQS Group to the
region (2, 0) to (22, 0): no valid locations in region
Info (175028): The DQS Group name: DQS_LOGIC_BLOCK_5~DQ_X8/9
Info (175015): The I/O pad is constrained to the location PIN_AP28
due to: User Location Constraints (PIN_AP28)
Error (171000): Can't fit design in device
The workaround for this issue is as follows:
- Open the file xxx_addr_cmd_pads.v in a text editor.
- Search for the localparam
USE_ADDR_CMD_CPS_FOR_MEM_CK
and set its value totrue
.
This issue will be fixed in a future version.