单启动光盘的Booting Catalog有2个部分,一个是Validation Entry,一个是Initial/Default Entry
Validation Entry每个字节的含义如下
Initial/Default Entry每个字节的含义如下
具体到这张盘,Booting Catalog如下
从01.....55 AA是Validation Entry
从88 03 开始的2行是Initial/Default Entry
根据上面Validation Entry每个字节的含义和Initial/Default Entry每个字节的含义
可以看出这个Booting Catalog设置的是
1.80X86的平台的启动映像(Validation Entry第2个字节是00)
2.是个2.88M软盘映像 (Initial/Default Entry第2个字节是03)
3.这个2.88M软盘的LBA地址是17, 17是Sector 23 (17是16进制的，把它变为10进制就是23)
(2048*23=47104 就是这个2.88M文件在光盘中的物理地址)
Initial/Default Entry 里第9个字节,就是上面写17的这个位置，是根据实际的实际的磁盘映像存放LBA地址来写的
获得磁盘映像LBA的方法
在第一步建立ISO时,那个磁盘映像肯定有名子，例如为boot288.img 用16进制编辑器打开做完的ISO映像之后,查找
boot288这个ASCII码,找到后把光标防在ASCII区第一个字母上,向上移2行,再向右移一次,这时16进制区里面光标所在
的位置的信息就是这个映像的LBA地址。将这个地址，写入Initial/Default Entry的第9个字节就可以了
根据自己的实际情况，更改好上面的Boot Record Volume,Validation Entry,Initial/Default Entry之后存盘.这个单启动光盘映像就做好了
The Booting Catalog of a single - boot CD has 2 parts, one is the Validation Entry and the other is the Initial/Default Entry.
The meaning of each byte of the Validation Entry is as follows
The meaning of each byte of the Initial/Default Entry is as follows
Specifically to this disc, the Booting Catalog is as follows
From 01.....55 AA is the Validation Entry
From 88 03 onwards are 2 lines of the Initial/Default Entry
According to the meaning of each byte of the Validation Entry and the meaning of each byte of the Initial/Default Entry above, it can be seen that this Booting Catalog is set as
1. The boot image of the 80X86 platform (the second byte of the Validation Entry is 00)
2. It is a 2.88M floppy disk image (the second byte of the Initial/Default Entry is 03)
3. The LBA address of this 2.88M floppy disk is 17. 17 is in hexadecimal. Converting it to decimal is 23. (2048 * 23 = 47104 is the physical address of this 2.88M file in the CD)
The 9th byte in the Initial/Default Entry, which is the position where 17 is written above, is written according to the actual LBA address where the disk image is stored.
The method to obtain the LBA of the disk image
In the first step of creating the ISO, that disk image must have a name, for example, boot288.img. After opening the created ISO image with a hexadecimal editor, search for the ASCII code of boot288. After finding it, place the cursor on the first letter in the ASCII area, move up 2 lines, and then move right once. At this time, the information in the hexadecimal area where the cursor is located is the LBA address of this image. Write this address into the 9th byte of the Initial/Default Entry.
After modifying the above Boot Record Volume, Validation Entry, and Initial/Default Entry according to your actual situation, save the file. This single - boot CD image is ready.
