10     pub starting_sector_cylinder: u16, // sector : 低6, cylinder : 高10;   起始扇区号 + 起始柱面号
13     pub ending_sector_cylingder: u16, // ending_sector : 低6, ending_cylinder : 高10;  结束扇区号 + 结束柱面号
19     pub fn starting_sector(&self) -> u16 {  in starting_sector()  argument
20         return self.starting_sector_cylinder & ((1 << 6) - 1) as u16;  in starting_sector()
22     pub fn starting_cylinder(&self) -> u16 {  in starting_cylinder()  argument
23         return (self.starting_sector_cylinder >> 6) & ((1 << 10) - 1) as u16;  in starting_cylinder()
25     pub fn ending_sector(&self) -> u16 {  in ending_sector()  argument
26         return self.ending_sector_cylingder & ((1 << 6) - 1) as u16;  in ending_sector()
28     pub fn ending_cylinder(&self) -> u16 {  in ending_cylinder()  argument
29         return (self.ending_sector_cylingder >> 6) & ((1 << 10) - 1) as u16;  in ending_cylinder()
39     pub bs_trailsig: u16,