关于单片机编程魔法疑问

只看该作者 · 2016-11-9 08:30

if(isTask_3_Living) //如果任务3活着
{
isTask_3_Living += myThread(&Task3, &Task3_Thread_Process);
}

只看该作者 · 2016-11-9 08:45

char myThread(myTask *Task, unsigned char *Process)
｛
...................
if(*Process>4)
{
ret = -1; //线程结束
*Process = 0;
}

return ret;
｝
如果线程结束时返回-1 如果线程没有结束一直返回0，那么unsigned char isTask_3_Living = 5; isTask_3_Living += myThread(&Task3, &Task3_Thread_Process); unsigned char Task3_Thread_Process = 0; if(isTask_3_Living) isTask_3_Living = 0时任务三线程才结束，可是 isTask_3_Living += myThread(&Task3, &Task3_Thread_Process);循环5次才返回-1，什么时候任务三线程才结束呢？有点不理解！请指教！谢谢！

只看该作者 · 2016-11-9 15:29

#include <stdlib.h>

typedef struct _myTask
{
struct _coefficient
{
unsigned char a;
unsigned char b;
unsigned char c;
} co;

struct _variable
{
unsigned int x;
unsigned long y;
} v;
} myTask;

#define THREAD_OVER -1
#define THREAD_NOTOVER 0

char myThread(myTask *Task, unsigned char *Process)
{
unsigned int z;
char ret = 0;

switch(*Process)
{
case 0:
Task->v.x = rand();
Task->v.y = 3;
break;
case 1:
Task->v.y *= Task->v.x;
Task->v.y *= Task->v.x;
break;
case 2:
z = 7 * Task->co.a * Task->co.b * Task->v.x;
Task->v.y += z;
break;
case 3:
z = Task->co.c;
Task->v.y += z;
}

(*Process)++;
if(*Process>4)
{
ret = -1;
*Process = 0;
}

return ret;
}

myTask Task1, Task2, Task3;

void InitTask(myTask *Task, unsigned char a, unsigned char b, unsigned char c)
{
Task->co.a = a;
Task->co.b = b;
Task->co.c = c;
}

main(void)
{

bit isTask_1_Living = 1;
unsigned char Task1_Thread_Process = 0;

bit isTask_2_Living = 1;
unsigned char Task2_Thread_Process = 0;

unsigned char isTask_3_Living = 5;
unsigned char Task3_Thread_Process = 0;

InitTask(&Task1, 9, 7, 18);
InitTask(&Task2, 4, 13, 16);
InitTask(&Task3, 2, 24, 3);

while(1)
{
if(isTask_1_Living)
{
isTask_1_Living = !myThread(&Task1, &Task1_Thread_Process);
}

if(isTask_2_Living)
{
isTask_2_Living = !myThread(&Task2, &Task2_Thread_Process);
}

if(isTask_3_Living)
{
isTask_3_Living += myThread(&Task3, &Task3_Thread_Process);//isTask_3_Living = isTask_3_Living + myThread(&Task3, &Task3_Thread_Process)
}
}
}
这是整个程序代码！请指教一下！非常感谢！

只看该作者 · 2016-11-9 21:04

其实我是这里不理解: if(isTask_1_Living) 这句代码判断任务一活着就执行isTask_1_Living = !myThread(&Task1, &Task1_Thread_Process);而myThread(&Task1, &Task1_Thread_Process)返回0或-1，那么这个任务永远执行着如果myThread(&Task1, &Task1_Thread_Process)返回-1，！-1等于？