|
这个可能和特定的编译器有关，但是有一点我们可以适当关注，那就是编程器(软件)。<br /> 因为常用的编程工具软件(调试及下载工具)往往考虑了这个细节，也就是说，软件在装载了用户代码之后，自动计算生成校验码并放到合适的位置，然后才开始下载到芯片中。这种情况下，编译器生成的代码中，向量位置不必是校验和为零的数据。<br /> 当我们用到那些不支持该特性的工具软件时，我们才需要手工计算该值。<br /><br />At 0x14 the user should insert a signature (checksum). This signature enables the bootloader to determine if there is valid user code in the Flash. <b><u>Currently most of the Flash programming tools (debuggers and ISP utility) have this feature built-in so the end user need not worry about it.</u></b> If the tool does not provide this feature then the value has to be computed manually and has to be inserted at 0x14. Details on computation of checksum could be found in the Flash programming chapter in the ARM LPC device User Manual.
|
楼主
