PROCEDURE ParkDisk; 
  VAR Regs: Registers; 
  BEGIN 
    Regs.AL := $00; 
    Intr($13,Regs); 
    Assert((Regs.Flags AND FCarry) = 0, 
      'Error getting disk parameters - AL returns '+IntToStr  (Regs.AL,0)); 
    Regs.AH := $0C; 
    Regs.DL := $80; 
    Intr($13,Regs); 
    Assert((Regs.Flags AND FCarry) = 0, 
      'Error parking disk - AL returns '+IntToStr(Regs.AL,0)); 
  END;       
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