Release 6.2i - ngdbuild G.28Copyright (c) 1995-2004 Xilinx, Inc.  All rights reserved.Command Line: ngdbuild -dd _ngo -uc lcd.ucf -p xc9500xl lcd.ngc lcd.ngd Reading NGO file "H:/CindyWang/mars/cpld/lcd/lcd/lcd.ngc" ...Reading component libraries for design expansion...Annotating constraints to design from file "lcd.ucf" ...Checking timing specifications ...Checking expanded design ...ERROR:NgdBuild:604 - logical block 'mydff1' with type 'dff' could not be
   resolved. A pin name misspelling can cause this, a missing edif or ngc file,
   or the misspelling of a type name. Symbol 'dff' is not supported in target
   'xc9500xl'.ERROR:NgdBuild:604 - logical block 'mydff2' with type 'dff' could not be
   resolved. A pin name misspelling can cause this, a missing edif or ngc file,
   or the misspelling of a type name. Symbol 'dff' is not supported in target
   'xc9500xl'.NGDBUILD Design Results Summary:  Number of errors:     2  Number of warnings:   0Total memory usage is 41120 kilobytesOne or more errors were found during NGDBUILD.  No NGD file will be written.Writing NGDBUILD log file "lcd.bld"...