Texas Instruments TMS320C54x, User Manual

Page: 359 / 469

File Header Structure
A-5 Common Object File Format
A.2 File Header Structure
The file header contains 22 bytes of information that describe the general
format of an object file. Table A–1 shows the structure of the COFF file header.
Table A–1. File Header Contents
Byte
Number
Type Description
0–1 Unsigned short integer Version id; indicates version of COFF file
structure
2–3 Unsigned short integer Number of section headers
4–7 Long integer Time and date stamp; indicates when the file
was created
8–11 Long integer File pointer; contains the symbol table’s
starting address
12–15 Long integer Number of entries in the symbol table
16–17 Unsigned short integer Number of bytes in the optional header. This
field is either 0 or 28; if it is 0, then there is no
optional file header
18–19 Unsigned short integer Flags (see Table A–2)
20–21 Unsigned short integer Target id; magic number indicates the file
can be executed in a TMS320C54x system
Table A–2 lists the flags that can appear in bytes 18 and 19 of the file header.
Any number and combination of these flags can be set at the same time (for
example, if bytes 18 and 19 are set to 0003h, F_RELFLG and F_EXEC are
both set.)
Table A–2. File Header Flags (Bytes 18 and 19)
Mnemonic Flag Description
F_RELFLG 0001h Relocation information was stripped from the file.
F_EXEC 0002h The file is relocatable (it contains no unresolved
external references).
F_LNNO 0004h Line numbers were stripped from the file.
F_LSYMS 0010h Local symbols were stripped from the file.
F_LENDIAN 0100h The file has the byte ordering used by ’C54x
devices (16 bits per word, least significant byte first)
F_SYMMERGE 1000h Duplicate symbols were removed.