ARM中的RO、RW、ZI的内容

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RO = 代码段(.text) + 常量数据段(.constdata) + ...(something I don't know now)
RW = 变量数据段(.data)
ZI = BSS数据段(.bss)

这里RO运行前运行后都只保存在flash中；RW运行前保存在flash中，运行后copy至RAM；ZI同RW一样，只是ZI在flash中没有初始化值。

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