mirror of
https://github.com/FreeRTOS/FreeRTOS-Kernel.git
synced 2025-08-20 01:58:32 -04:00
Add FreeRTOS-Plus directory.
This commit is contained in:
parent
7bd5f21ad5
commit
f508a5f653
6798 changed files with 134949 additions and 19 deletions
657
FreeRTOS/Source/portable/MPLAB/PIC18F/port.c
Normal file
657
FreeRTOS/Source/portable/MPLAB/PIC18F/port.c
Normal file
|
@ -0,0 +1,657 @@
|
|||
/*
|
||||
FreeRTOS V7.1.1 - Copyright (C) 2012 Real Time Engineers Ltd.
|
||||
|
||||
|
||||
***************************************************************************
|
||||
* *
|
||||
* FreeRTOS tutorial books are available in pdf and paperback. *
|
||||
* Complete, revised, and edited pdf reference manuals are also *
|
||||
* available. *
|
||||
* *
|
||||
* Purchasing FreeRTOS documentation will not only help you, by *
|
||||
* ensuring you get running as quickly as possible and with an *
|
||||
* in-depth knowledge of how to use FreeRTOS, it will also help *
|
||||
* the FreeRTOS project to continue with its mission of providing *
|
||||
* professional grade, cross platform, de facto standard solutions *
|
||||
* for microcontrollers - completely free of charge! *
|
||||
* *
|
||||
* >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
|
||||
* *
|
||||
* Thank you for using FreeRTOS, and thank you for your support! *
|
||||
* *
|
||||
***************************************************************************
|
||||
|
||||
|
||||
This file is part of the FreeRTOS distribution.
|
||||
|
||||
FreeRTOS is free software; you can redistribute it and/or modify it under
|
||||
the terms of the GNU General Public License (version 2) as published by the
|
||||
Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
|
||||
>>>NOTE<<< The modification to the GPL is included to allow you to
|
||||
distribute a combined work that includes FreeRTOS without being obliged to
|
||||
provide the source code for proprietary components outside of the FreeRTOS
|
||||
kernel. FreeRTOS 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 and the FreeRTOS license exception along with FreeRTOS; if not it
|
||||
can be viewed here: http://www.freertos.org/a00114.html and also obtained
|
||||
by writing to Richard Barry, contact details for whom are available on the
|
||||
FreeRTOS WEB site.
|
||||
|
||||
1 tab == 4 spaces!
|
||||
|
||||
***************************************************************************
|
||||
* *
|
||||
* Having a problem? Start by reading the FAQ "My application does *
|
||||
* not run, what could be wrong? *
|
||||
* *
|
||||
* http://www.FreeRTOS.org/FAQHelp.html *
|
||||
* *
|
||||
***************************************************************************
|
||||
|
||||
|
||||
http://www.FreeRTOS.org - Documentation, training, latest information,
|
||||
license and contact details.
|
||||
|
||||
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
|
||||
including FreeRTOS+Trace - an indispensable productivity tool.
|
||||
|
||||
Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell
|
||||
the code with commercial support, indemnification, and middleware, under
|
||||
the OpenRTOS brand: http://www.OpenRTOS.com. High Integrity Systems also
|
||||
provide a safety engineered and independently SIL3 certified version under
|
||||
the SafeRTOS brand: http://www.SafeRTOS.com.
|
||||
*/
|
||||
|
||||
/*
|
||||
Changes between V1.2.4 and V1.2.5
|
||||
|
||||
+ Introduced portGLOBAL_INTERRUPT_FLAG definition to test the global
|
||||
interrupt flag setting. Using the two bits defined within
|
||||
portINITAL_INTERRUPT_STATE was causing the w register to get clobbered
|
||||
before the test was performed.
|
||||
|
||||
Changes from V1.2.5
|
||||
|
||||
+ Set the interrupt vector address to 0x08. Previously it was at the
|
||||
incorrect address for compatibility mode of 0x18.
|
||||
|
||||
Changes from V2.1.1
|
||||
|
||||
+ PCLATU and PCLATH are now saved as part of the context. This allows
|
||||
function pointers to be used within tasks. Thanks to Javier Espeche
|
||||
for the enhancement.
|
||||
|
||||
Changes from V2.3.1
|
||||
|
||||
+ TABLAT is now saved as part of the task context.
|
||||
|
||||
Changes from V3.2.0
|
||||
|
||||
+ TBLPTRU is now initialised to zero as the MPLAB compiler expects this
|
||||
value and does not write to the register.
|
||||
*/
|
||||
|
||||
/* Scheduler include files. */
|
||||
#include "FreeRTOS.h"
|
||||
#include "task.h"
|
||||
|
||||
/* MPLAB library include file. */
|
||||
#include "timers.h"
|
||||
|
||||
/*-----------------------------------------------------------
|
||||
* Implementation of functions defined in portable.h for the PIC port.
|
||||
*----------------------------------------------------------*/
|
||||
|
||||
/* Hardware setup for tick. */
|
||||
#define portTIMER_FOSC_SCALE ( ( unsigned long ) 4 )
|
||||
|
||||
/* Initial interrupt enable state for newly created tasks. This value is
|
||||
copied into INTCON when a task switches in for the first time. */
|
||||
#define portINITAL_INTERRUPT_STATE 0xc0
|
||||
|
||||
/* Just the bit within INTCON for the global interrupt flag. */
|
||||
#define portGLOBAL_INTERRUPT_FLAG 0x80
|
||||
|
||||
/* Constant used for context switch macro when we require the interrupt
|
||||
enable state to be unchanged when the interrupted task is switched back in. */
|
||||
#define portINTERRUPTS_UNCHANGED 0x00
|
||||
|
||||
/* Some memory areas get saved as part of the task context. These memory
|
||||
area's get used by the compiler for temporary storage, especially when
|
||||
performing mathematical operations, or when using 32bit data types. This
|
||||
constant defines the size of memory area which must be saved. */
|
||||
#define portCOMPILER_MANAGED_MEMORY_SIZE ( ( unsigned char ) 0x13 )
|
||||
|
||||
/* We require the address of the pxCurrentTCB variable, but don't want to know
|
||||
any details of its type. */
|
||||
typedef void tskTCB;
|
||||
extern volatile tskTCB * volatile pxCurrentTCB;
|
||||
|
||||
/* IO port constants. */
|
||||
#define portBIT_SET ( ( unsigned char ) 1 )
|
||||
#define portBIT_CLEAR ( ( unsigned char ) 0 )
|
||||
|
||||
/*
|
||||
* The serial port ISR's are defined in serial.c, but are called from portable
|
||||
* as they use the same vector as the tick ISR.
|
||||
*/
|
||||
void vSerialTxISR( void );
|
||||
void vSerialRxISR( void );
|
||||
|
||||
/*
|
||||
* Perform hardware setup to enable ticks.
|
||||
*/
|
||||
static void prvSetupTimerInterrupt( void );
|
||||
|
||||
/*
|
||||
* ISR to maintain the tick, and perform tick context switches if the
|
||||
* preemptive scheduler is being used.
|
||||
*/
|
||||
static void prvTickISR( void );
|
||||
|
||||
/*
|
||||
* ISR placed on the low priority vector. This calls the appropriate ISR for
|
||||
* the actual interrupt.
|
||||
*/
|
||||
static void prvLowInterrupt( void );
|
||||
|
||||
/*
|
||||
* Macro that pushes all the registers that make up the context of a task onto
|
||||
* the stack, then saves the new top of stack into the TCB.
|
||||
*
|
||||
* If this is called from an ISR then the interrupt enable bits must have been
|
||||
* set for the ISR to ever get called. Therefore we want to save the INTCON
|
||||
* register with the enable bits forced to be set - and ucForcedInterruptFlags
|
||||
* must contain these bit settings. This means the interrupts will again be
|
||||
* enabled when the interrupted task is switched back in.
|
||||
*
|
||||
* If this is called from a manual context switch (i.e. from a call to yield),
|
||||
* then we want to save the INTCON so it is restored with its current state,
|
||||
* and ucForcedInterruptFlags must be 0. This allows a yield from within
|
||||
* a critical section.
|
||||
*
|
||||
* The compiler uses some locations at the bottom of the memory for temporary
|
||||
* storage during math and other computations. This is especially true if
|
||||
* 32bit data types are utilised (as they are by the scheduler). The .tmpdata
|
||||
* and MATH_DATA sections have to be stored in there entirety as part of a task
|
||||
* context. This macro stores from data address 0x00 to
|
||||
* portCOMPILER_MANAGED_MEMORY_SIZE. This is sufficient for the demo
|
||||
* applications but you should check the map file for your project to ensure
|
||||
* this is sufficient for your needs. It is not clear whether this size is
|
||||
* fixed for all compilations or has the potential to be program specific.
|
||||
*/
|
||||
#define portSAVE_CONTEXT( ucForcedInterruptFlags ) \
|
||||
{ \
|
||||
_asm \
|
||||
/* Save the status and WREG registers first, as these will get modified \
|
||||
by the operations below. */ \
|
||||
MOVFF WREG, PREINC1 \
|
||||
MOVFF STATUS, PREINC1 \
|
||||
/* Save the INTCON register with the appropriate bits forced if \
|
||||
necessary - as described above. */ \
|
||||
MOVFF INTCON, WREG \
|
||||
IORLW ucForcedInterruptFlags \
|
||||
MOVFF WREG, PREINC1 \
|
||||
_endasm \
|
||||
\
|
||||
portDISABLE_INTERRUPTS(); \
|
||||
\
|
||||
_asm \
|
||||
/* Store the necessary registers to the stack. */ \
|
||||
MOVFF BSR, PREINC1 \
|
||||
MOVFF FSR2L, PREINC1 \
|
||||
MOVFF FSR2H, PREINC1 \
|
||||
MOVFF FSR0L, PREINC1 \
|
||||
MOVFF FSR0H, PREINC1 \
|
||||
MOVFF TABLAT, PREINC1 \
|
||||
MOVFF TBLPTRU, PREINC1 \
|
||||
MOVFF TBLPTRH, PREINC1 \
|
||||
MOVFF TBLPTRL, PREINC1 \
|
||||
MOVFF PRODH, PREINC1 \
|
||||
MOVFF PRODL, PREINC1 \
|
||||
MOVFF PCLATU, PREINC1 \
|
||||
MOVFF PCLATH, PREINC1 \
|
||||
/* Store the .tempdata and MATH_DATA areas as described above. */ \
|
||||
CLRF FSR0L, 0 \
|
||||
CLRF FSR0H, 0 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF POSTINC0, PREINC1 \
|
||||
MOVFF INDF0, PREINC1 \
|
||||
MOVFF FSR0L, PREINC1 \
|
||||
MOVFF FSR0H, PREINC1 \
|
||||
/* Store the hardware stack pointer in a temp register before we \
|
||||
modify it. */ \
|
||||
MOVFF STKPTR, FSR0L \
|
||||
_endasm \
|
||||
\
|
||||
/* Store each address from the hardware stack. */ \
|
||||
while( STKPTR > ( unsigned char ) 0 ) \
|
||||
{ \
|
||||
_asm \
|
||||
MOVFF TOSL, PREINC1 \
|
||||
MOVFF TOSH, PREINC1 \
|
||||
MOVFF TOSU, PREINC1 \
|
||||
POP \
|
||||
_endasm \
|
||||
} \
|
||||
\
|
||||
_asm \
|
||||
/* Store the number of addresses on the hardware stack (from the \
|
||||
temporary register). */ \
|
||||
MOVFF FSR0L, PREINC1 \
|
||||
MOVF PREINC1, 1, 0 \
|
||||
_endasm \
|
||||
\
|
||||
/* Save the new top of the software stack in the TCB. */ \
|
||||
_asm \
|
||||
MOVFF pxCurrentTCB, FSR0L \
|
||||
MOVFF pxCurrentTCB + 1, FSR0H \
|
||||
MOVFF FSR1L, POSTINC0 \
|
||||
MOVFF FSR1H, POSTINC0 \
|
||||
_endasm \
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* This is the reverse of portSAVE_CONTEXT. See portSAVE_CONTEXT for more
|
||||
* details.
|
||||
*/
|
||||
#define portRESTORE_CONTEXT() \
|
||||
{ \
|
||||
_asm \
|
||||
/* Set FSR0 to point to pxCurrentTCB->pxTopOfStack. */ \
|
||||
MOVFF pxCurrentTCB, FSR0L \
|
||||
MOVFF pxCurrentTCB + 1, FSR0H \
|
||||
\
|
||||
/* De-reference FSR0 to set the address it holds into FSR1. \
|
||||
(i.e. *( pxCurrentTCB->pxTopOfStack ) ). */ \
|
||||
MOVFF POSTINC0, FSR1L \
|
||||
MOVFF POSTINC0, FSR1H \
|
||||
\
|
||||
/* How many return addresses are there on the hardware stack? Discard \
|
||||
the first byte as we are pointing to the next free space. */ \
|
||||
MOVFF POSTDEC1, FSR0L \
|
||||
MOVFF POSTDEC1, FSR0L \
|
||||
_endasm \
|
||||
\
|
||||
/* Fill the hardware stack from our software stack. */ \
|
||||
STKPTR = 0; \
|
||||
\
|
||||
while( STKPTR < FSR0L ) \
|
||||
{ \
|
||||
_asm \
|
||||
PUSH \
|
||||
MOVF POSTDEC1, 0, 0 \
|
||||
MOVWF TOSU, 0 \
|
||||
MOVF POSTDEC1, 0, 0 \
|
||||
MOVWF TOSH, 0 \
|
||||
MOVF POSTDEC1, 0, 0 \
|
||||
MOVWF TOSL, 0 \
|
||||
_endasm \
|
||||
} \
|
||||
\
|
||||
_asm \
|
||||
/* Restore the .tmpdata and MATH_DATA memory. */ \
|
||||
MOVFF POSTDEC1, FSR0H \
|
||||
MOVFF POSTDEC1, FSR0L \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, POSTDEC0 \
|
||||
MOVFF POSTDEC1, INDF0 \
|
||||
/* Restore the other registers forming the tasks context. */ \
|
||||
MOVFF POSTDEC1, PCLATH \
|
||||
MOVFF POSTDEC1, PCLATU \
|
||||
MOVFF POSTDEC1, PRODL \
|
||||
MOVFF POSTDEC1, PRODH \
|
||||
MOVFF POSTDEC1, TBLPTRL \
|
||||
MOVFF POSTDEC1, TBLPTRH \
|
||||
MOVFF POSTDEC1, TBLPTRU \
|
||||
MOVFF POSTDEC1, TABLAT \
|
||||
MOVFF POSTDEC1, FSR0H \
|
||||
MOVFF POSTDEC1, FSR0L \
|
||||
MOVFF POSTDEC1, FSR2H \
|
||||
MOVFF POSTDEC1, FSR2L \
|
||||
MOVFF POSTDEC1, BSR \
|
||||
/* The next byte is the INTCON register. Read this into WREG as some \
|
||||
manipulation is required. */ \
|
||||
MOVFF POSTDEC1, WREG \
|
||||
_endasm \
|
||||
\
|
||||
/* From the INTCON register, only the interrupt enable bits form part \
|
||||
of the tasks context. It is perfectly legitimate for another task to \
|
||||
have modified any other bits. We therefore only restore the top two bits. \
|
||||
*/ \
|
||||
if( WREG & portGLOBAL_INTERRUPT_FLAG ) \
|
||||
{ \
|
||||
_asm \
|
||||
MOVFF POSTDEC1, STATUS \
|
||||
MOVFF POSTDEC1, WREG \
|
||||
/* Return enabling interrupts. */ \
|
||||
RETFIE 0 \
|
||||
_endasm \
|
||||
} \
|
||||
else \
|
||||
{ \
|
||||
_asm \
|
||||
MOVFF POSTDEC1, STATUS \
|
||||
MOVFF POSTDEC1, WREG \
|
||||
/* Return without effecting interrupts. The context may have \
|
||||
been saved from a critical region. */ \
|
||||
RETURN 0 \
|
||||
_endasm \
|
||||
} \
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* See header file for description.
|
||||
*/
|
||||
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
|
||||
{
|
||||
unsigned long ulAddress;
|
||||
unsigned char ucBlock;
|
||||
|
||||
/* Place a few bytes of known values on the bottom of the stack.
|
||||
This is just useful for debugging. */
|
||||
|
||||
*pxTopOfStack = 0x11;
|
||||
pxTopOfStack++;
|
||||
*pxTopOfStack = 0x22;
|
||||
pxTopOfStack++;
|
||||
*pxTopOfStack = 0x33;
|
||||
pxTopOfStack++;
|
||||
|
||||
|
||||
/* Simulate how the stack would look after a call to vPortYield() generated
|
||||
by the compiler.
|
||||
|
||||
First store the function parameters. This is where the task will expect to
|
||||
find them when it starts running. */
|
||||
ulAddress = ( unsigned long ) pvParameters;
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) ( ulAddress & ( unsigned long ) 0x00ff );
|
||||
pxTopOfStack++;
|
||||
|
||||
ulAddress >>= 8;
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) ( ulAddress & ( unsigned long ) 0x00ff );
|
||||
pxTopOfStack++;
|
||||
|
||||
/* Next we just leave a space. When a context is saved the stack pointer
|
||||
is incremented before it is used so as not to corrupt whatever the stack
|
||||
pointer is actually pointing to. This is especially necessary during
|
||||
function epilogue code generated by the compiler. */
|
||||
*pxTopOfStack = 0x44;
|
||||
pxTopOfStack++;
|
||||
|
||||
/* Next are all the registers that form part of the task context. */
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x66; /* WREG. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0xcc; /* Status. */
|
||||
pxTopOfStack++;
|
||||
|
||||
/* INTCON is saved with interrupts enabled. */
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) portINITAL_INTERRUPT_STATE; /* INTCON */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x11; /* BSR. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x22; /* FSR2L. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x33; /* FSR2H. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x44; /* FSR0L. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x55; /* FSR0H. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x66; /* TABLAT. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x00; /* TBLPTRU. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x88; /* TBLPTRUH. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x99; /* TBLPTRUL. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0xaa; /* PRODH. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0xbb; /* PRODL. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x00; /* PCLATU. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x00; /* PCLATH. */
|
||||
pxTopOfStack++;
|
||||
|
||||
/* Next the .tmpdata and MATH_DATA sections. */
|
||||
for( ucBlock = 0; ucBlock <= portCOMPILER_MANAGED_MEMORY_SIZE; ucBlock++ )
|
||||
{
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) ucBlock;
|
||||
*pxTopOfStack++;
|
||||
}
|
||||
|
||||
/* Store the top of the global data section. */
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) portCOMPILER_MANAGED_MEMORY_SIZE; /* Low. */
|
||||
pxTopOfStack++;
|
||||
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 0x00; /* High. */
|
||||
pxTopOfStack++;
|
||||
|
||||
/* The only function return address so far is the address of the
|
||||
task. */
|
||||
ulAddress = ( unsigned long ) pxCode;
|
||||
|
||||
/* TOS low. */
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) ( ulAddress & ( unsigned long ) 0x00ff );
|
||||
pxTopOfStack++;
|
||||
ulAddress >>= 8;
|
||||
|
||||
/* TOS high. */
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) ( ulAddress & ( unsigned long ) 0x00ff );
|
||||
pxTopOfStack++;
|
||||
ulAddress >>= 8;
|
||||
|
||||
/* TOS even higher. */
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) ( ulAddress & ( unsigned long ) 0x00ff );
|
||||
pxTopOfStack++;
|
||||
|
||||
/* Store the number of return addresses on the hardware stack - so far only
|
||||
the address of the task entry point. */
|
||||
*pxTopOfStack = ( portSTACK_TYPE ) 1;
|
||||
pxTopOfStack++;
|
||||
|
||||
return pxTopOfStack;
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
portBASE_TYPE xPortStartScheduler( void )
|
||||
{
|
||||
/* Setup a timer for the tick ISR is using the preemptive scheduler. */
|
||||
prvSetupTimerInterrupt();
|
||||
|
||||
/* Restore the context of the first task to run. */
|
||||
portRESTORE_CONTEXT();
|
||||
|
||||
/* Should not get here. Use the function name to stop compiler warnings. */
|
||||
( void ) prvLowInterrupt;
|
||||
( void ) prvTickISR;
|
||||
|
||||
return pdTRUE;
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
void vPortEndScheduler( void )
|
||||
{
|
||||
/* It is unlikely that the scheduler for the PIC port will get stopped
|
||||
once running. If required disable the tick interrupt here, then return
|
||||
to xPortStartScheduler(). */
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Manual context switch. This is similar to the tick context switch,
|
||||
* but does not increment the tick count. It must be identical to the
|
||||
* tick context switch in how it stores the stack of a task.
|
||||
*/
|
||||
void vPortYield( void )
|
||||
{
|
||||
/* This can get called with interrupts either enabled or disabled. We
|
||||
will save the INTCON register with the interrupt enable bits unmodified. */
|
||||
portSAVE_CONTEXT( portINTERRUPTS_UNCHANGED );
|
||||
|
||||
/* Switch to the highest priority task that is ready to run. */
|
||||
vTaskSwitchContext();
|
||||
|
||||
/* Start executing the task we have just switched to. */
|
||||
portRESTORE_CONTEXT();
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Vector for ISR. Nothing here must alter any registers!
|
||||
*/
|
||||
#pragma code high_vector=0x08
|
||||
static void prvLowInterrupt( void )
|
||||
{
|
||||
/* Was the interrupt the tick? */
|
||||
if( PIR1bits.CCP1IF )
|
||||
{
|
||||
_asm
|
||||
goto prvTickISR
|
||||
_endasm
|
||||
}
|
||||
|
||||
/* Was the interrupt a byte being received? */
|
||||
if( PIR1bits.RCIF )
|
||||
{
|
||||
_asm
|
||||
goto vSerialRxISR
|
||||
_endasm
|
||||
}
|
||||
|
||||
/* Was the interrupt the Tx register becoming empty? */
|
||||
if( PIR1bits.TXIF )
|
||||
{
|
||||
if( PIE1bits.TXIE )
|
||||
{
|
||||
_asm
|
||||
goto vSerialTxISR
|
||||
_endasm
|
||||
}
|
||||
}
|
||||
}
|
||||
#pragma code
|
||||
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* ISR for the tick.
|
||||
* This increments the tick count and, if using the preemptive scheduler,
|
||||
* performs a context switch. This must be identical to the manual
|
||||
* context switch in how it stores the context of a task.
|
||||
*/
|
||||
static void prvTickISR( void )
|
||||
{
|
||||
/* Interrupts must have been enabled for the ISR to fire, so we have to
|
||||
save the context with interrupts enabled. */
|
||||
portSAVE_CONTEXT( portGLOBAL_INTERRUPT_FLAG );
|
||||
PIR1bits.CCP1IF = 0;
|
||||
|
||||
/* Maintain the tick count. */
|
||||
vTaskIncrementTick();
|
||||
|
||||
#if configUSE_PREEMPTION == 1
|
||||
{
|
||||
/* Switch to the highest priority task that is ready to run. */
|
||||
vTaskSwitchContext();
|
||||
}
|
||||
#endif
|
||||
|
||||
portRESTORE_CONTEXT();
|
||||
}
|
||||
/*-----------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Setup a timer for a regular tick.
|
||||
*/
|
||||
static void prvSetupTimerInterrupt( void )
|
||||
{
|
||||
const unsigned long ulConstCompareValue = ( ( configCPU_CLOCK_HZ / portTIMER_FOSC_SCALE ) / configTICK_RATE_HZ );
|
||||
unsigned long ulCompareValue;
|
||||
unsigned char ucByte;
|
||||
|
||||
/* Interrupts are disabled when this function is called.
|
||||
|
||||
Setup CCP1 to provide the tick interrupt using a compare match on timer
|
||||
1.
|
||||
|
||||
Clear the time count then setup timer. */
|
||||
TMR1H = ( unsigned char ) 0x00;
|
||||
TMR1L = ( unsigned char ) 0x00;
|
||||
|
||||
/* Set the compare match value. */
|
||||
ulCompareValue = ulConstCompareValue;
|
||||
CCPR1L = ( unsigned char ) ( ulCompareValue & ( unsigned long ) 0xff );
|
||||
ulCompareValue >>= ( unsigned long ) 8;
|
||||
CCPR1H = ( unsigned char ) ( ulCompareValue & ( unsigned long ) 0xff );
|
||||
|
||||
CCP1CONbits.CCP1M0 = portBIT_SET; /*< Compare match mode. */
|
||||
CCP1CONbits.CCP1M1 = portBIT_SET; /*< Compare match mode. */
|
||||
CCP1CONbits.CCP1M2 = portBIT_CLEAR; /*< Compare match mode. */
|
||||
CCP1CONbits.CCP1M3 = portBIT_SET; /*< Compare match mode. */
|
||||
PIE1bits.CCP1IE = portBIT_SET; /*< Interrupt enable. */
|
||||
|
||||
/* We are only going to use the global interrupt bit, so set the peripheral
|
||||
bit to true. */
|
||||
INTCONbits.GIEL = portBIT_SET;
|
||||
|
||||
/* Provided library function for setting up the timer that will produce the
|
||||
tick. */
|
||||
OpenTimer1( T1_16BIT_RW & T1_SOURCE_INT & T1_PS_1_1 & T1_CCP1_T3_CCP2 );
|
||||
}
|
||||
|
Loading…
Add table
Add a link
Reference in a new issue