hex.htm

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information within this record.</pre>
    <pre>load offset
this field contains 030303030h, the hexadecimal encoding of the
ascii characters '0000', since this field is not used for this
record.</pre>
    <pre>rectyp
this field contains 03032h, the hexadecimal encoding of the ascii
character '02', which specifies the record type to be an extended
segment address record.</pre>
    <pre>usba
this field contains four ascii hexadecimal digits that specify the
16-bit upper segment base address value.  the high-order byte is the
10th/1lth character pair of the record.  the low-order byte is the
12th/13th character pair of the record.</pre>
    <pre>chksum
this field contains the check sum on the reclen, load offset,
rectyp, and usba fields.</pre>
    <pre>5.    data record   (8-, 16-, or 32-bit formats)</pre>
    <pre>| record  |     load     |         |         |         |         |
|  mark   |    reclen    | offset  | rectyp  |  data   | chksum  |
|  ':'    |              |         |  '00'   |         |         |
  1-byte       1-byte      2-bytes   1-byte    n-bytes   1-byte
</pre>
    <pre>the data record provides a set of hexadecimal digits that represent
the ascii code for data bytes that make up a portion of a memory
image.  the method for calculating the absolute address (linear in
the 8-bit and 32-bit case and segmented in the 16-bit case) for each
byte of data is described in the discussions of the extended linear
address record and the extended segment address record.</pre>
    <pre>the contents of the individual fields within the record are:</pre>
    <pre>record mark
this field contains 03ah, the hexadecimal encoding of the ascii
colon (':') character.</pre>
    <pre>reclen
the field contains two ascii hexadecimal digits that specify the
number of data bytes in the record.  the maximum value is 'ff' or
04646h (255 decimal).</pre>
    <pre>load offset
this field contains four ascii hexadecimal digits representing the
offset from the lba (see extended linear address record) or sba (see
extended segment address record) defining the address which the
first byte of the data is to be placed.</pre>
    <pre>rectyp
this field contains 03030h, the hexadecimal encoding of the ascii
character '00', which specifies the record type to be a data record.</pre>
    <pre>data
this field contains pairs of ascii hexadecimal digits, one pair for
each data byte.</pre>
    <pre>chksum
this field contains the check sum on the reclen, load offset,
rectyp, and data fields.
</pre>
    <pre>6.    start linear address record  (32-bit format only)</pre>
    <pre>| record  |     load     |         |         |         |         |
|  mark   |    reclen    | offset  | rectyp  |  eip    | chksum  |
|  ':'    |    '04'      | '0000'  |  '05'   |         |         |
  1-byte       1-byte      2-bytes   1-byte    4-bytes   1-byte
</pre>
    <pre>the start linear address record is used to specify the execution
start address for the object file.  the value given is the 32-bit
linear address for the eip register.  note that this record only
specifies the code address within the 32-bit linear address space of
the 80386.  if the code is to start execution in the real mode of
the 80386, then the start segment address record should be used
instead, since that record specifies both the cs and ip register
contents necessary for real mode.</pre>
    <pre>the start linear address record can appear anywhere in a 32-bit
hexadecimal object file.  if such a record is not present in a
hexadecimal object file, a loader is free to assign a default start
address.</pre>
    <pre>the contents of the individual fields within the record are:</pre>
    <pre>record mark
this field contains 03ah, the hexadecimal encoding of the ascii
colon (':') character.</pre>
    <pre>reclen
the field contains 03034h, the hexadecimal encoding of the ascii
characters '04', which is the length, in bytes, of the eip register
content within this record.</pre>
    <pre>load offset
this field contains 030303030h, the hexadecimal encoding of the
ascii characters '0000', since this field is not used for this
record.</pre>
    <pre>rectyp
this field contains 03035h, the hexadecimal encoding of the ascii
character '05', which specifies the record type to be a start linear
address record.</pre>
    <pre>eip
this field contains eight ascii hexadecimal digits that specify the
32-bit eip register contents.  the high-order byte is the 10th/1lth
character pair.</pre>
    <pre>chksum
this field contains the check sum on the reclen, load offset,
rectyp, and eip fields.
</pre>
    <pre>7.    start segment address record (16- or 32-bit formats)</pre>
    <pre>| record  |     load     |         |         |         |         |
|  mark   |    reclen    | offset  | rectyp  |  cs/ip  | chksum  |
|  ':'    |    '04'      | '0000'  |  '03'   |         |         |
  1-byte       1-byte      2-bytes   1-byte    4-bytes   1-byte
</pre>
    <pre>the start segment address record is used to specify the execution
start address for the object file.  the value given is the 20-bit
segment address for the cs and ip registers.  note that this record
only specifies the code address within the 20-bit segmented address
space of the 8086/80186.</pre>
    <pre>the start segment address record can appear anywhere in a 16-bit
hexadecimal object file.   if such a record is not present in a
hexadecimal object file, a loader is free to assign a default start
address.</pre>
    <pre>the contents of the individual fields within the record are:</pre>
    <pre>record mark
this field contains 03ah, the hexadecimal encoding of the ascii
colon (':') character.</pre>
    <pre>reclen
the field contains 03034h, the hexadecimal encoding of the ascii
characters '04', which is the length, in bytes, of the cs/ip
register contents within this record.</pre>
    <pre>load offset
this field contains 030303030h, the hexadecimal encoding of the
ascii characters '0000', since this field is not used for this
record.</pre>
    <pre>rectyp
this field contains 03033h, the hexadecimal encoding of the ascii
character '03', which specifies the record type to be a start
segment address record.</pre>
    <pre>cs/ip
this field contains eight ascii hexadecimal digits that specify the
16-bit cs register and 16-bit ip register contents.  the high-order
byte of the cs register content is the 10th/llth character pair, the
low-order byte is the 12th/13th character pair of the record.  the
high-order byte of the ip register content is the 14th/15th
character pair, the low-order byte is the 16th/17th character pair
of the record.</pre>
    <pre>chksum
this field contains the check sum on the reclen, load offset,
rectyp, and cs/ip fields.

</pre>
    <pre>8.   end of file record  (8-, 16-, or 32-bit formats)</pre>
    <pre>| record  |     load     |         |         |         |
|  mark   |    reclen    | offset  | rectyp  | chksum  |
|  ':'    |    '00'      | '0000'  |  '01'   |         |
  1-byte       1-byte      2-bytes   1-byte    1-byte</pre>
    <pre>the end of file record specifies the end of the hexadecimal object
file.</pre>
    <pre>the contents of the individual fields within the record are:</pre>
    <pre>record  mark
this field contains 03ah, the hexadecimal encoding of the ascii
colon (':') character.</pre>
    <pre>reclen
the field contains 03030h, the hexadecimal encoding of the ascii
characters '00'.  since this record does not contain any info/data
bytes, the length is zero.</pre>
    <pre>load  offset
this field contains 030303030h, the hexadecimal encoding of the
ascii characters '0000', since this field is not used for this
record.</pre>
    <pre>rectyp
this field contains 03031h, the hexadecimal encoding of the ascii
character '01', which specifies the record type to be an end of file
record.</pre>
    <pre>chksum
this field contains the check sum an the reclen, load offset, and
rectyp fields.  since all the fields are static, the check sum can
also be calculated statically, and the value is 04646h, the
hexadecimal encoding of the ascii characters 'ff'.d</pre>
    </td>
  </tr>
</table>
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