/*
*********************************************************************************************************
*                                               uC/OS-II
*                                        The Real-Time Kernel
*
*                         (c) Copyright 1992-2002, Jean J. Labrosse, Weston, FL
*                                          All Rights Reserved
*
*                                       80x86/80x88 Specific code
*                                          LARGE MEMORY MODEL
*                                With Floating-Point Register Support
*
*                                         Borland C/C++ V4.51
*
* File         : OS_CPU.H
* By           : Jean J. Labrosse
*********************************************************************************************************
*/

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

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


typedef unsigned char  BOOLEAN;
typedef unsigned char  INT8U;                    /* Unsigned  8 bit quantity                           */
typedef signed   char  INT8S;                    /* Signed    8 bit quantity                           */
typedef unsigned int   INT16U;                   /* Unsigned 16 bit quantity                           */
typedef signed   int   INT16S;                   /* Signed   16 bit quantity                           */
typedef unsigned long  INT32U;                   /* Unsigned 32 bit quantity                           */
typedef signed   long  INT32S;                   /* Signed   32 bit quantity                           */
typedef float          FP32;                     /* Single precision floating point                    */
typedef double         FP64;                     /* Double precision floating point                    */
typedef INT16U             OS_FLAGS;   /* Date type for event flag bits (8, 16 or 32 bits)             */

typedef unsigned char  OS_STK;                   /* Each stack entry is 16-bit wide                    */


/* 
*********************************************************************************************************
*                              Intel 80x86 (Real-Mode, Large Model)
*
* 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.
*
* Method #3:  Disable/Enable interrupts by preserving the state of interrupts.  Generally speaking you
*             would store the state of the interrupt disable flag in the local variable 'cpu_sr' and then
*             disable interrupts.  'cpu_sr' is allocated in all of uC/OS-II's functions that need to 
*             disable interrupts.  You would restore the interrupt disable state by copying back 'cpu_sr'
*             into the CPU's status register.
*********************************************************************************************************
*/


#define  OS_ENTER_CRITICAL()  EA=0;           /* Disable interrupts                        */
#define  OS_EXIT_CRITICAL()   EA=1;                   /* Enable  interrupts                        */

/*
*********************************************************************************************************
*                           Intel 80x86 (Real-Mode, Large Model) Miscellaneous
*********************************************************************************************************
*/
#define MaxStkSize 64
#define  OS_STK_GROWTH        0                      /* Stack grows from HIGH to LOW memory on 80x86  */


#define OS_CRITICAL_METHOD   2
#define  OS_TASK_SW()         OSCtxSw()

/*
*********************************************************************************************************
*                                            GLOBAL VARIABLES