os_cpu.h

8051单片机的ucos移植

/*
*********************************************************************************************************
*                                               uC/OS-II
*                                        The Real-Time Kernel
*
*                        (c) Copyright 1992-1998, Jean J. Labrosse, Plantation, FL
*                                          All Rights Reserved
*
*                                       8051 Specific code
*                                         Compact Model
*
* File : OS_CPU.H
* By   : Wai Chan
*********************************************************************************************************
*/

#ifdef  OS_CPU_GLOBALS
#define OS_CPU_EXT
#else
#define OS_CPU_EXT  extern
#endif

/*
*********************************************************************************************************
*                                              DATA TYPES
*                                         (Compiler Specific)
*********************************************************************************************************
*/

#define BOOLEAN        unsigned char  
#define INT8U          unsigned char             /* Unsigned  8 bit quantity                           */
#define INT8S             char             /* Signed    8 bit quantity                           */
#define INT16U         unsigned int              /* Unsigned 16 bit quantity                           */
#define INT16S         signed   int              /* Signed   16 bit quantity                           */
#define INT32U         unsigned int             /* Unsigned 32 bit quantity                           */
#define INT32S         signed   int             /* Signed   32 bit quantity                           */
#define FP32           float                     /* Single precision floating point                    */
#define FP54           double                    /* Double precision floating point                    */

#define OS_STK         unsigned char             /* Each stack entry is 8-bit wide                    */

#define BYTE           INT8S                     /* Define data types for backward compatibility ...   */
#define UBYTE          INT8U                     /* ... to uC/OS V1.xx.  Not actually needed for ...   */
#define WORD           INT16S                    /* ... uC/OS-II.                                      */
#define UWORD          INT16U
#define LONG           INT32S
#define ULONG          INT32U

/* 
*********************************************************************************************************
*                              Intel 8051
*
* Method #1:  Disable/Enable interrupts using simple instructions.  After critical section, interrupts
*             will be enabled even if they were disabled before entering the critical section. 
*
* Method #2:  Disable/Enable interrupts by preserving the state of interrupts.  In other words, if 
*             interrupts were disabled before entering the critical section, they will be disabled when
*             leaving the critical section.
*********************************************************************************************************
*/
#define  OS_CRITICAL_METHOD    2

#if      OS_CRITICAL_METHOD == 1
#define  OS_ENTER_CRITICAL()  IE &= 0x7F  /* Disable interrupts                            */
#define  OS_EXIT_CRITICAL()   IE |= 0x80  /* Enable  interrupts                            */
#endif

#if      OS_CRITICAL_METHOD == 2
#define  OS_ENTER_CRITICAL()  IE_SHADOW = IE; IE &= 0x7F   /* Disable interrupts                            */
#define  OS_EXIT_CRITICAL()   IE = IE_SHADOW               /* Enable  interrupts                            */
#endif


/*
*********************************************************************************************************
*                           Intel 8051  Miscellaneous
*********************************************************************************************************
*/

#define  OS_STK_GROWTH        1                       /* Stack grows from HIGH to LOW memory */

#define  OS_TASK_SW()         OSCtxSw()

/* global variable used by OS_ENTER_CRITICAL() and OS_EXIT_CRITICAL */
OS_CPU_EXT  INT8U  IE_SHADOW;

/* global variable used by OSTaskStkInit() */
OS_CPU_EXT  INT8U  ISTK_START;

/* global variable used to keep counting how many times Ticker has been called */
OS_CPU_EXT  INT16U    OSTickCtr;

/* Assuming we are using 11.0592 MHz oscillator and Timer 0 Mode 0 */
/* the math: 11059200 / 2^13 */
#define TIMER_TICKS_PER_SECOND    1350  

/* Used to adjust the ticker call frequency */
OS_CPU_EXT  INT16U    OSTickFrequency;