68hc16.txt

ucos在摩托罗拉16位微控制器68hc16上的移植

/*
						    Gary Schneider
						    Systems Software Engineer
						    Aeroflex Labs.
						    35 South Service Rd.
						    Plainview, NY 11803
						    516-752-2421




    Mr. Jean Labrosse:


       This disk contains the code to run the uCOS kernal on
   a M68HC16 micro-controller.  The \SOURCE directory contains
   the code which is not microprocessor specific.  The \M68HC16
   directory contains the code which allows UCOS to be ported
   to a M68HC16.  The \OBJ directory contains the relocatable
   object files and output file produced by the INTROL compiler,
   assembler and linker.  Note that the file MAIN.ABS can run
   on an emulator and MAIN.HEX is suitable for the target proms.
   Also, this directory contains the *.mix files which are produced
   by INTROL'S IMERGE.EXE.

       Thank you for your time and patience in answering all of my
   questions concerning your uCOS kernal.  I look forward to using your
   kernal in my next project and if you have any questions (or improvements)
   concerning my code don't hesitate to call!



			     Thank You,

			     Gary Schneider
*/


/*
*********************************************************************************************************
*                                                uCOS
*                        Microcomputer Real-Time Multitasking Operating System
*
*                         (c) Copyright 1992, Jean J. Labrosse, Plantation, FL
*                                          All Rights Reserved
*
*                                       68HC16 Specific code
*
* Filename : DEFS.H
* By       : GGS
*********************************************************************************************************
*/

/*
*********************************************************************************************************
*                                              CONSTANTS
*********************************************************************************************************
*/

#define  FALSE    0
#define  TRUE     1

/*
*********************************************************************************************************
*                                                MACROS
*********************************************************************************************************
*/

#define  OS_ENTER_CRITICAL()  asm(" ORP    #$00E0");
#define  OS_EXIT_CRITICAL()   asm(" ANDP   #$FF1F");
#define  OS_TASK_SW()         asm(" SWI    uCOS");

/*
*********************************************************************************************************
*                                              DATA TYPES
*********************************************************************************************************
*/

typedef unsigned char  BOOLEAN;
typedef unsigned char  UBYTE;                    /* Unsigned  8 bit quantity                           */
typedef signed   char  BYTE;                     /* Signed    8 bit quantity                           */
typedef unsigned int   UWORD;                    /* Unsigned 16 bit quantity                           */
typedef signed   int   WORD;                     /* Signed   16 bit quantity                           */
typedef unsigned long  ULONG;                    /* Unsigned 32 bit quantity                           */
typedef signed   long  LONG;                     /* Signed   32 bit quantity                           */


/*
**************************************************************************
*                                 uCOS
*         Microcomputer Real-Time Multitasking Operating System
*
*          (c) Copyright 1992, Jean J. Labrosse, Plantation, FL
*                           All Rights Reserved
*
*
*                          MC68HC16 Specific code
*
* File : task16.C
* By   : Gary Schneider
**************************************************************************
*/

#include "DEFS.H"
#include "UCOS.H"

/*
**************************************************************************
*                         CREATE A TASK
**************************************************************************
*/
UBYTE OSTaskCreate( void (*task) (void), void *pstk, UBYTE p)
{													 
    UWORD *stk;
    UBYTE  err;

    OS_ENTER_CRITICAL();
    if (OSTCBPrioTbl[p] == (OS_TCB *)0) {   /* Make sure task doesn't already exist at this priority   */
        OS_EXIT_CRITICAL();
        stk    = (UWORD *) pstk;            /* Load stack pointer                                      */
                                            /* Load the PC                                             */
                                            /* RTI subtracts 6 bytes (3 words) from PC due to pipeline */
        *--stk = (UWORD) (((ULONG) task)+4);
        *--stk = (UWORD) (((ULONG) task)>>16);  /* Load PK onto stack                                  */
        *--stk = (UWORD) ((ULONG) task);        /* Place-holder since SP gets                          */
			                        /* incr. by 2 by an RTI                                */
        *--stk = (UWORD)0x0000;             /* Accumulator D = 0                                       */
        *--stk = (UWORD)0x0000;             /* Accumulator E = 0                                       */
        *--stk = (UWORD)0x0000;             /* IX = 0                                                  */
        *--stk = (UWORD)0x0000;             /* IY = 0                                                  */
        *--stk = (UWORD)0x0000;             /* IZ = 0                                                  */
        *--stk = (UWORD)0x0000;             /* XK,YK,ZK = 0                                            */
        err = OSTCBInit(p, (void *)stk);    /* Get and initialize a TCB                                */
        if (err == OS_NO_ERR) {
            if (OSRunning) {                /* Find highest priority task if multitasking has started  */
                OSSched();
            }
        }
        return (err);
    } else {
        OS_EXIT_CRITICAL();
        return (OS_PRIO_EXIST);
    }
}


**************************************************************************
*                                    uCOS
*            Microcomputer Real-Time Multitasking Operating System
*
*             (c) Copyright 1992, Jean J. Labrosse, Plantation, FL
*                              All Rights Reserved
*
*
*                         MC68HC16 Specific code
*
* File :  tasksw16.s
* By   :   Gary Schneider
***************************************************************************

             export OSStartHighRdy
             export OSCtxSw
             export OSIntCtxSw

             import OSIntEnter
             import OSIntExit
             import OSTimeTick
             import OSTCBCur
             import OSTCBHighRdy

        section		.text

******************************************************************
*                        START MULTITASKING
*                    void OSStartHighRdy(void)
*
******************************************************************

OSStartHighRdy:
	    LDAB  #OSTCBHighRdy>>16
	    TBXK
	    LDX   OSTCBHighRdy
            MOVW  OSTCBHighRdy,OSTCBCur    * Point to TCB of highest priority task ready to run
                                           * OSTCBCur = OSTCBHighRdy
	    LDS   $0,X                    * SP = OSTCBHighRdy->OSTCBStkPtr
               
	    PULM  D,E,X,Y,Z,K    	   * Load task's context
            RTI			           * Run task

********************************************************************
*            PERFORM A CONTEXT SWITCH (From task level)
*                       void OSCtxSw(void)
*
********************************************************************
       
OSCtxSw:
            PSHM   D,E,X,Y,Z,K            * Save current task's context

	    LDAB  #OSTCBHighRdy>>16
	    TBXK
	    LDX    OSTCBHighRdy
	    LDAB  #OSTCBCur>>16
	    TBYK
	    LDY    OSTCBCur
	    STS    $0,Y                   * OSTCBCur->OSTCBStkPtr = SP
            MOVW   OSTCBHighRdy,OSTCBCur  * OSTCBCur = OSTCBHighRdy
	    LDS    $0,X                   * SP = OSTCBHighRdy->OSTCBStkPtr

	    PULM   D,E,X,Y,Z,K               * Load task's context
            RTI                              * Return to new task

************************************************************************
*                 PERFORM A CONTEXT SWITCH (From an ISR)
*                         void OSIntCtxSw(void)
************************************************************************

OSIntCtxSw:
	    AIS	   #$0C	    * Ignore calls to OSIntExit and OSIntCtxSw (8 bytes)
	                     * Call to OSIntExit does pshm z,k  (4 bytes)
	    LDAB  #OSTCBHighRdy>>16
	    TBXK
	    LDX    OSTCBHighRdy
	    LDAB  #OSTCBCur>>16
	    TBYK
	    LDY    OSTCBCur
	    STS    $0,Y                      * OSTCBCur->OSTCBStkPtr = SP
            MOVW   OSTCBHighRdy,OSTCBCur     * OSTCBCur = OSTCBHighRdy
	    LDS    $0,X                      * SP = OSTCBHighRdy->OSTCBStkPtr

	    PULM   D,E,X,Y,Z,K    	     * Load task's context
            RTI                              * Return to new task


*---------------------------------------------------------------------
*                                    uCOS
*            Microcomputer Real-Time Multitasking Operating System
*                                   KERNEL
*             (c) Copyright 1992, Jean J. Labrosse, Plantation, FL
*                              All Rights Reserved
*
*
* Filename: TICK16.S
*
*