ex_p6_13_create_new_data.vhd

This is the course for VHDL programming

use STD.TEXTIO.all;
entity FILEWRT_NEW is end FILEWRT_NEW;
architecture arch of FILEWRT_NEW is
    type REC_OLD_T is record
         x,y,z,u,v,w:bit;
	 end record;
	 type REC_NEW_T is record
         a,b:bit;
	 end record;
    type OLD_FILE_T is file of REC_OLD_T;
    type UPDATE_FILE_T is file of REC_OLD_T;
    type NEW_FILE_T is file of REC_NEW_T;
BEGIN
  PROCESS
	file FILE_OBJ_OLD:OLD_FILE_T 
	   open READ_MODE is "OLD_DATA";
	file FILE_OBJ_NEW:NEW_FILE_T 
	   open READ_MODE is "NEW_RESULT";
	file FILE_OBJ_UPDATE:OLD_FILE_T 
	   open WRITE_MODE is "NEW_DATA";
	variable R_OLD:REC_OLD_T;
	variable R_NEW:REC_NEW_T;
	variable lout:LINE;
  begin
   while not ENDFILE(FILE_OBJ_OLD) loop
      READ(FILE_OBJ_OLD, R_OLD);
      READ(FILE_OBJ_NEW, R_NEW);
      R_OLD.v := R_NEW.a;
      R_OLD.w := R_NEW.b;
      WRITE(FILE_OBJ_UPDATE, R_OLD);
	   WRITE(lout,R_OLD.x,LEFT,4);WRITE(lout,R_OLD.y,LEFT,4);
      WRITE(lout,R_OLD.z,LEFT,4);WRITE(lout,R_OLD.u,LEFT,4);
      WRITE(lout,R_OLD.v,LEFT,4);WRITE(lout,R_OLD.w,LEFT,4);
      WRITELINE(OUTPUT, lout);
   end loop;
	WRITE(lout, string'("Updated file written\n"));
   WRITELINE(OUTPUT, lout);
   FILE_CLOSE(FILE_OBJ_OLD);
   FILE_CLOSE(FILE_OBJ_NEW);
   FILE_CLOSE(FILE_OBJ_UPDATE);
	wait;
  END PROCESS;
END arch ;