一、
1 AREA RESET, DATA, READONLY 2 EXPORT __Vectors 3 EXPORT __Vectors_End 4 EXPORT __Vectors_Size 5 IMPORT |Image$$ARM_LIB_STACK$$ZI$$Limit|
1、AREA 指令
The AREA directive instructs the assembler to assemble a new code or data section. Sections are independent, named, indivisible chunks of code or data that are manipulated by the linker.
AREAsectionname{,attr}{,attr}...
1 AREA RESET, DATA, READONLY ;分配一个新的数据段 RESET, 属性为只读
2、EXPORT 指令
TheEXPORTdirective declares a symbol that can be used by the linker to resolve symbol references in separate object and library files.
EXPORT 命令声明一个符号，可由链接器用于解释各个目标和库文件中的符号引用，相当于声明了一个全局变量。
2 EXPORT __Vectors
3 EXPORT __Vectors_End
4 EXPORT __Vectors_Size ；声明三个符号 __Vectors、__Vectors_End、 __Vectors_Size；
3、IMPORT 指令
imports the symbol unconditionally
5 IMPORT |Image$$ARM_LIB_STACK$$ZI$$Limit| ;
4、DCD 指令
The DCD directive allocates one or more words of memory, aligned on four-byte boundaries, and defines the initial runtime contents of the memory.
原文：http://www.cnblogs.com/Iamchritian--forthegloryofGod/p/7751613.html