"ERROR:Pack:625 - The dual data rate register XLXI_26 failed to combine with output buffer XLXI_19 as required. Register XLXI_26 set/reset disagrees with another register in the I/O component."
"ERROR:Pack:626 - The dual data rate register XLXI_26 failed to join an I/O component as required. Please try constraining the register together with a valid pad or output buffer symbol. Note that FDDR library symbols may drive output buffers only."