/*看大家都在学操作系统，我也想学学。所以想用51写一个来玩玩，发现比较郁闷。



弄了几下，不想再弄了，51弄这个没啥意思。我用的89S52，除了速度慢，RAM资源 太少之外，其它都还过得去。弄了一点代码出来，放在那也没啥用，不如拿上来 给新手看看，一个任务调度的雏形是什么样子的~~~~~~~~~这些代码没有经过优化， 我只求实现任务切换的功能。



利用定时器2产生10mS的定时中断作为时钟节拍，任务切换时保存工作寄存器等操作 嵌入了汇编指令，因此Task_Switch.C文件要做相应的设置才能编译通过。受硬件资源和编译器的限制，有很多无奈。程序只好这样写了，不管怎么说，到底是能调度起来了。



注：这里是老版本，后面又改动的新版本。-/ * see everyone in school operating systems, I also want to learn. So I would like to use 51 to write a play and found to be relatively depressed. Get a few, do not want to wander and get the 51 lacks meaning. I use the 89S52, in addition to the slow speed, RAM too few resources, the other is still decent. Get a bit code and placed it also lacks used, it is better to put up with the newcomers to see, a task scheduling is a prototype of what the code of ~~~~~~~~~ without optimization, I want to achieve task switching function. Use timers 10mS two have regularly interrupted as the clock rhythms, task switching preservation register as a compilation of embedded operating instructions, therefore Task_Switch.C document to be done to set up the corresponding compile. By hardware resources and c