What can cause a calibration failure on the odd numbered ranks of a multiple rank DDR3 or DDR4 interface ? - What can cause a calibration failure on the odd numbered ranks of a multiple rank DDR3 or DDR4 interface ? Description If you observe a calibration failure on only the odd numbered ranks of a DDR3 or DDR4 interface, this may be due to address mirroring not being enabled in the external memory interface IP parameters. Resolution Multiple rank DIMMs often use a feature known as address mirroring on the odd numbered ranks to optimize the PCB layout of the address signals. Check your DIMM datasheet or contact the DIMM manufacturer to find out if the DIMM PCB layout uses address mirroring and set the IP parameter correctly. Arria® 10 External Memory Interfaces IP and Stratix® 10 External Memory Interfaces IP : Memory tab > Topology > Enable address mirroring for odd ranks DDR3 SDRAM Controller with UniPHY : Memory Parameters tab > Memory Initialization Options > Mirror Addressing: 1 per chip select Custom Fields values: ['novalue'] Troubleshooting FB: 474391; False ['DDR3 SDRAM Controller with UniPHY IP', 'External Memory Interfaces Arria® 10 FPGA IP', 'External Memory Interfaces Stratix® 10 FPGA IP'] ['novalue'] novalue novalue ['Arria® V GZ FPGA', 'Arria® 10 FPGAs and SoCs', 'Stratix® 10 FPGAs and SoCs', 'Stratix® V FPGAs'] ['novalue'] ['novalue'] ['novalue']