ex8.c

51单片机上可以使用的操作系统

//
// example 8: Use mail to create complex task:
//		 1.The main program creates first task and runs OS kenel.
//		 2.First task creates second task, 
//		 send the third task's structure including parameter and address and so on
//		 and turn on lamp every other 17 tick.
//		 3. Second task receives mailbox create third task and turn on lamp every other 11 tick.
//		 4. After third task delay 4 second, it delete first task and second task and display lamp. 
// author: Taiyun Wang 
// date:2003/2/22
///////////////////////////////////////////////////////////////////////////

#include "sposvar.h"
#include "spos.h"

typedef struct {
	void (*start_add)(void *para);	//function pointer
	void* para;						//task parameter 
	int* stacktop;					//task stack size
	int priority;					//task priority
} stru_task;						//structure name

int err;							//Error No
int t1stack[30];					//Task 1 stack
int t2stack[30];					//Task 2 stack
int t3stack[30];					//Task 3 stack
HEvent mailbox;						//Event handle


volatile unsigned int *P_IOB_BUFFER =(unsigned int*)(0x7006);	//Port B data register
volatile unsigned int *P_IOB_DIR =(unsigned int*)(0x7007);		//Port B direction register
volatile unsigned int *P_IOB_ATTRIB = (unsigned int*)(0x7008);	//Port B attribute register

main()
{
	void Task1();
	SpSInit();
	*P_IOB_DIR = 0XFFFF;						//Set port B direction
	*P_IOB_ATTRIB = 0XFFFF;						//Set prot B attribute
	err = SpSTaskCreate(Task1,0,t1stack+29,1);	//Create first task
	mailbox = SpSMboxCreate((void*)0);			//create mailbox
	SpSStart();									//Start OS kernel
}
void Task1() 			                       
{
	void Task2();
	void Task3();
	stru_task msg;
	msg.start_add = Task3;
	msg.para = (void*) 0;
	msg.stacktop = t3stack+29;
	msg.priority = 3;
	err = SpSTaskCreate(Task2,0,t2stack+29,2);	//Create second task
	SpSTimeDly(20);								//Delay 20 tick,running task2
	SpSMboxPost(mailbox,&msg);					//Send mail to task 2
	while(1) {
		*P_IOB_BUFFER = 0x55;
		SpSTimeDly(17);
	}
}
void Task2()
{
	stru_task msg;
	stru_task* pmsg;
	int err;
	pmsg = SpSMboxPend(mailbox,0,&err);			//Waiting mail
	msg = *pmsg;								//copy mail to local variable
	//create task 3
	err = SpSTaskCreate(msg.start_add,msg.para,msg.stacktop,msg.priority); 
	while(1) {
		*P_IOB_BUFFER = 0xAA;
		SpSTimeDly(11);
	}
}
void Task3()
{
	int i = 1;
	SpSTimeDly(512);							//Delay 512 tick
	SpSTaskDel(1);								//Delete task 1
	SpSTaskDel(2);								//Delete task 2
	while(1) {					
		*P_IOB_BUFFER = i;
		i <<=1;
		if (i == 0x100)
			i = 1;
		SpSTimeDly(20);							//Delay 20 tick
	}
}