ucosiito51.txt

在51单片机上移植UCOS2

        ;恢复现场堆栈内容
        MOV  R0,#OSStkStart
        
restore_stack:
    
        INC  DPTR
        INC  R0
        MOVX A,@DPTR
        MOV  @R0,A
        DJNZ R5,restore_stack
    
        ;恢复堆栈指针SP
        MOV  SP,R0
    
        ;OSRunning=TRUE
        MOV  R0,#LOW (OSRunning)
        MOV  @R0,#01
    
        POPALL
        SETB EA    ;开中断
        RETI
;-------------------------------------------------------------------------
        RSEG ?PR?OSCtxSw?OS_CPU_A
OSCtxSw:    
        PUSHALL
    
OSIntCtxSw_in:
    
        ;获得堆栈长度和起址
        MOV  A,SP
        CLR  C
        SUBB A,#OSStkStart
        MOV  R5,A     ;获得堆栈长度        
    
        ;OSTCBCur ===> DPTR  获得当前TCB指针，详见C51.PDF第178页
        MOV  R0,#LOW (OSTCBCur) ;获得OSTCBCur指针低地址，指针占3字节。+0类型+1高8位数据+2低8位数据
        INC  R0
        MOV  DPH,@R0    ;全局变量OSTCBCur在IDATA中
        INC  R0
        MOV  DPL,@R0
    
        ;OSTCBCur->OSTCBStkPtr ===> DPTR  获得用户堆栈指针
        INC  DPTR        ;指针占3字节。+0类型+1高8位数据+2低8位数据
        MOVX A,@DPTR     ;.OSTCBStkPtr是void指针
        MOV  R0,A
        INC  DPTR
        MOVX A,@DPTR
        MOV  R1,A
        MOV  DPH,R0
        MOV  DPL,R1
        
        ;保存堆栈长度
        MOV  A,R5
        MOVX @DPTR,A
    
        MOV  R0,#OSStkStart  ;获得堆栈起址
save_stack:
    
        INC  DPTR
        INC  R0
        MOV  A,@R0
        MOVX @DPTR,A
        DJNZ R5,save_stack
    
        ;调用用户程序
        LCALL _?OSTaskSwHook
        
        ;OSTCBCur = OSTCBHighRdy
        MOV  R0,#OSTCBCur
    MOV  R1,#OSTCBHighRdy
    MOV  A,@R1
        MOV  @R0,A
        INC  R0
    INC  R1
    MOV  A,@R1
        MOV  @R0,A
        INC  R0
    INC  R1
    MOV  A,@R1
        MOV  @R0,A
                
        ;OSPrioCur = OSPrioHighRdy  使用这两个变量主要目的是为了使指针比较变为字节比较，以便节省时间。
        MOV  R0,#OSPrioCur
    MOV  R1,#OSPrioHighRdy
    MOV  A,@R1
        MOV  @R0,A
        
        LJMP OSCtxSw_in
;-------------------------------------------------------------------------
        RSEG ?PR?OSIntCtxSw?OS_CPU_A
        
OSIntCtxSw:

        ;调整SP指针去掉在调用OSIntExit(),OSIntCtxSw()过程中压入堆栈的多余内容
        ;SP=SP-4

        MOV  A,SP
        CLR  C
        SUBB A,#4
        MOV  SP,A
        
        LJMP OSIntCtxSw_in
;-------------------------------------------------------------------------
        CSEG AT 000BH    ;OSTickISR
        LJMP OSTickISR   ;使用定时器0
        RSEG ?PR?OSTickISR?OS_CPU_A

OSTickISR:        
        
        USING 0        
        PUSHALL
        
        CLR  TR0
        MOV  TH0,#70H    ;定义Tick=50次/秒(即0.02秒/次)
        MOV  TL0,#00H    ;OS_CPU_C.C  和  OS_TICKS_PER_SEC
        SETB TR0
        
        LCALL _?OSIntEnter
        LCALL _?OSTimeTick
        LCALL _?OSIntExit
        POPALL        
        RETI
;-------------------------------------------------------------------------
        CSEG AT 0023H    ;串口中断
        LJMP SerialISR   ;工作于系统态，无任务切换。
        RSEG ?PR?_?serial?OS_CPU_A
        
SerialISR:
        
        USING 0        
        PUSHALL
        CLR  EA
        LCALL _?serial        
        SETB EA
        POPALL        
        RETI
;-------------------------------------------------------------------------
        END
;-------------------------------------------------------------------------

文件名 : OS_CPU_C.C

void *OSTaskStkInit (void (*task)(void *pd), void *ppdata, void *ptos, INT16U opt) reentrant
{    
    OS_STK *stk;

    ppdata = ppdata;
    opt    = opt;                           //opt没被用到，保留此语句防止告警产生    
    stk    = (OS_STK *)ptos;                //用户堆栈最低有效地址
    *stk++ = 15;                            //用户堆栈长度
    *stk++ = (INT16U)task & 0xFF;           //任务地址低8位
    *stk++ = (INT16U)task >> 8;             //任务地址高8位    
    *stk++ = 0x00;                          //PSW
    *stk++ = 0x0A;                          //ACC
    *stk++ = 0x0B;                          //B
    *stk++ = 0x00;                          //DPL
    *stk++ = 0x00;                          //DPH
    *stk++ = 0x00;                          //R0
    *stk++ = 0x01;                          //R1
    *stk++ = 0x02;                          //R2
    *stk++ = 0x03;                          //R3
    *stk++ = 0x04;                          //R4
    *stk++ = 0x05;                          //R5
    *stk++ = 0x06;                          //R6
    *stk++ = 0x07;                          //R7
                                            //不用保存SP，任务切换时根据用户堆栈长度计算得出。    
    return ((void *)ptos);
}

#if OS_CPU_HOOKS_EN
void OSTaskCreateHook (OS_TCB *ptcb) reentrant
{
    ptcb = ptcb;                       /* Prevent compiler warning                                     */
}

void OSTaskDelHook (OS_TCB *ptcb) reentrant
{
    ptcb = ptcb;                       /* Prevent compiler warning                                     */
}

void OSTimeTickHook (void) reentrant
{
}
#endif

//初始化定时器0
void InitTimer0(void) reentrant
{
    TMOD=TMOD&0xF0;
    TMOD=TMOD|0x01;    //模式1(16位定时器)，仅受TR0控制
    TH0=0x70;    //定义Tick=50次/秒(即0.02秒/次)
    TL0=0x00;    //OS_CPU_A.ASM  和  OS_TICKS_PER_SEC
    ET0=1;       //允许T0中断
    TR0=1;   
}

文件名 : YY.C

#include <includes.h>

#define MAX_STK_SIZE 64

void TaskStartyya(void *yydata) reentrant;
void TaskStartyyb(void *yydata) reentrant;
void TaskStartyyc(void *yydata) reentrant;

OS_STK TaskStartStkyya[MAX_STK_SIZE+1];//注意：我在ASM文件中设置?STACK空间为40H即64，不要超出范围。
OS_STK TaskStartStkyyb[MAX_STK_SIZE+1];//用户栈多一个字节存长度
OS_STK TaskStartStkyyc[MAX_STK_SIZE+1];

void main(void)
{
    OSInit();
    
    InitTimer0();
    InitSerial();
    InitSerialBuffer();
    
    OSTaskCreate(TaskStartyya, (void *)0, &TaskStartStkyya[0],2);
    OSTaskCreate(TaskStartyyb, (void *)0, &TaskStartStkyyb[0],3);
    OSTaskCreate(TaskStartyyc, (void *)0, &TaskStartStkyyc[0],4);
    
    OSStart();
}


void TaskStartyya(void *yydata) reentrant
{
    yydata=yydata;
    clrscr();
    PrintStr("\n\t\t*******************************\n");
    PrintStr("\t\t*     Hello! The world.       *\n");
    PrintStr("\t\t*******************************\n\n\n");
    
    for(;;){
        PrintStr("\tAAAAAA111111 is active.\n");
        OSTimeDly(OS_TICKS_PER_SEC);    
    }    
}

void TaskStartyyb(void *yydata) reentrant
{
    yydata=yydata; 
    
    for(;;){
        PrintStr("\tBBBBBB333333 is active.\n");
        OSTimeDly(3*OS_TICKS_PER_SEC);    
    }    
}

void TaskStartyyc(void *yydata) reentrant
{
    yydata=yydata; 
    
    for(;;){
        PrintStr("\tCCCCCC666666 is active.\n");
        OSTimeDly(6*OS_TICKS_PER_SEC);    
    }    
}