general_definitions.h

嵌入式操作系统EOS（Embedded OperatingSystem）是一种用途广泛的系统软件

/*
** Copyright (C) 2006 Tamir Michael
**  
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
** 
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
** GNU General Public License for more details.
** 
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software 
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/

#ifndef _GENERAL_DEFINITIONS
#define _GENERAL_DEFINITIONS

// basic data types
typedef unsigned char   int8u ;
typedef          char   int8s ;
typedef unsigned int    int16u ;
typedef          int    int16s ;
typedef unsigned long   int32u ;
typedef          long   int32s ;
typedef          float  float32 ;
typedef          double float64 ; 

// definitions for interrupt priority
#define IC_IE(x) 	(((x) == 0) ? 0x0000 : 0x0040)
#define IC_ILVL(x) 	(((x) << 2) & 0x003C)
#define IC_GLVL(x) 	((x) & 0x0003)

// WAR STORY
// the size of the trace buffer - very powerful feature for embedded debugging
// the user posts action codes into the buffer, where they stored along with the lower two bytes of the 
// tick count, allowing after-crash analysis/problem analysis at run time.
#define TRACE_BUFFER_SIZE       128
#define TRACE_BUFFER_END_MARKER 127 // this marker is needed in order to be able to observe where the trace buffer ends (the trace buffer is circular)

// handy for debugging
#define FLIP_PORT_BIT(x,b) 	P##x = ( ((P##x & 1<<b) == 1<<b ) ? (P##x & 0xFF^(1<<b)) : (P##x | 1<<b) ) ; // port x.b is used to indicate an administration switch. handy for debugging purposes.

// data structures
#define MAX_QUEUE_ELEMENTS 20 // must be >= MAX_TASKS, otherwise software errors can be expected due to queues that contain task ids over-following
// WAR STORY (was not implemented because it adds one instruction to the wraparound check in queue.c, 
// but it is handy anyway)
// this canstant is a power of 2 so that checking the top index can be done within 1 instruction:
// if the queue contains 32 items, indices 0..31 shall be used. in order to put the tail pointer of the queue at the
// first index is it goes beyond the last element (when the circular queue is not full), instead of doing a 
// comparision every operation to check the index location, is it faster to 'AND' the index
// with the mask 0x1F - this will have no effect on indices <=31, but once the index >31,  (31=0x1F=11111b ----(+1)----> 32=0x20=100000b)
// the "1" bit will be set to 0, so that the index returns to 0. this can only be done with array sizes that are a 
// power of 2 (because the mask that is used must be all '1's - a buffer size of 256 needs the mask 0x0FF, 0x1FF for
// 512 bytes etc.

// generate a random number
int32s 	g_generate_random_id() ;

// module interface starts here

// failure routines
void 	software_error(const char*, ...) ;
void 	software_warning(const char *, ...) ;

#endif