EMERSON KJ3243X1-BA1控制系统模块自动化
RAM已初始化，并从CPU地址0开始映射。 如果支持RAM ECC或奇偶校验，则已清除RAM中的ECC或奇偶错误。 活动闪存库（引导）从地址空间的上端映射。 如果由COPY_TO_RAM指定，则图像已复制到ImageRamAddress指定的地址处的RAM。 CPU寄存器R1（堆栈指针）已初始化为接近RAM末尾的值。 CPU寄存器R3被添加到以下结构中：typedef struct altBootData｛unsigned int ramSize；/*板的RAM大小（MB）*/void flashPtr；/*ptr to this image in flash*/char boardType[16]；/*name string，例如MVME7100*/void globalData；/*16K，归零，用户定义*/unsigned int-reserved[12]；}altBootData_t；备用引导数据结构备用引导数据数据结构的globalData字段指向RAM的一个区域，该区域被引导加载程序初始化为零。在执行POST映像或其他备用引导映像后，引导加载程序不会清除RAM的此区域。它旨在为用户提供一种将POST映像结果传递给后续引导映像的机制。引导加载程序除了在向POST、USER或Alternate MOTLoad映像传输控制之前指定的初始化之外，不执行其他板初始化。备用启动映像需要将板初始化为映像执行所需的任何状态。
RAM has been initialized and is mapped starting at CPU address 0.
If RAM ECC or parity is supported, RAM has been scrubbed of ECC or parity
errors.
The active flash bank (boot) is mapped from the upper end of the address space.
If specified by COPY_TO_RAM, the image has been copied to RAM at the address
specified by ImageRamAddress.
CPU register R1 (the stack pointer) has been initialized to a value near the end of
RAM.
CPU register R3 is added to the following structure:
typedef struct altBootData {
unsigned int ramSize;/* board's RAM size in MB */
void flashPtr;/* ptr to this image in flash */
char boardType[16];/* name string, eg MVME7100 */
void globalData;/* 16K, zeroed, user defined */
unsigned int reserved[12];
} altBootData_t;Alternate Boot Data Structure
The globalData field of the alternate boot data structure points to an area of RAM which
was initialized to zeros by the boot loader. This area of RAM is not cleared by the boot
loader after execution of a POST image, or other alternate boot image, is executed. It is
intended to provide a user a mechanism to pass POST image results to subsequent boot
images.
The boot loader performs no other initialization of the board than that specified prior to the
transfer of control to either a POST, USER, or Alternate MOTLoad image. Alternate boot
images need to initialize the board to whatever state the image may further require for its
execution.
