请教异常中断处理程序!
(2005-08-24 20:54:30) 柯南◆道尔(63008267)
在C程序中安装异常中断处理程序时
使用Load pc method
3. Subtract 0x8 to allow for prefetching.
5. Logically OR this with 0xe59FF000
为什么要减8而不是4?
为什么要和e59ff000作逻辑或??
INT32U InstallHandler(INT32U handler, INT32U *vector){
INT32U handler,oldvect;
vec = (handler - (INT32U)vector - 0x08) | 0xe59ff000; /* produce the value to be placed in the vector.*/
*vector = vec;
return (oldvect);
}