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/* ----------------------------------------------------------------------------

 *         ATMEL Microcontroller Software Support

 * ----------------------------------------------------------------------------

 * Copyright (c) 2008, Atmel Corporation

 *

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * - Redistributions of source code must retain the above copyright notice,

 * this list of conditions and the disclaimer below.

 *

 * Atmel's name may not be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE

 * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,

 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,

 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 * ----------------------------------------------------------------------------

 */

#include "ISR_Support.h"

/*

     IAR startup file for AT91SAM9XE microcontrollers.

 */

        MODULE  ?cstartup

        ;; Forward declaration of sections.

        SECTION IRQ_STACK:DATA:NOROOT(2)

        SECTION CSTACK:DATA:NOROOT(3)

//------------------------------------------------------------------------------

//         Headers

//------------------------------------------------------------------------------

#define __ASSEMBLY__

#include "board.h"

//------------------------------------------------------------------------------

//         Definitions

//------------------------------------------------------------------------------

#define ARM_MODE_ABT     0x17

#define ARM_MODE_FIQ     0x11

#define ARM_MODE_IRQ     0x12

#define ARM_MODE_SVC     0x13

#define ARM_MODE_SYS     0x1F

#define I_BIT            0x80

#define F_BIT            0x40

//------------------------------------------------------------------------------

//         Startup routine

//------------------------------------------------------------------------------

/*

   Exception vectors

 */

        SECTION .vectors:CODE:NOROOT(2)

        PUBLIC  resetVector

        PUBLIC  irqHandler

        EXTERN  Undefined_Handler

        EXTERN  vPortYieldProcessor

        EXTERN  Prefetch_Handler

        EXTERN  Abort_Handler

        EXTERN  FIQ_Handler

        ARM

__iar_init$$done:               ; The interrupt vector is not needed

                                ; until after copy initialization is done

resetVector:

        ; All default exception handlers (except reset) are

        ; defined as weak symbol definitions.

        ; If a handler is defined by the application it will take precedence.

        LDR     pc, =resetHandler        ; Reset

        LDR     pc, Undefined_Addr       ; Undefined instructions

        LDR     pc, SWI_Addr             ; Software interrupt (SWI/SVC)

        LDR     pc, Prefetch_Addr        ; Prefetch abort

        LDR     pc, Abort_Addr           ; Data abort

        B       .                        ; RESERVED

        LDR     pc, =irqHandler          ; IRQ

        LDR     pc, FIQ_Addr             ; FIQ

Undefined_Addr: DCD   Undefined_Handler

SWI_Addr:       DCD   vPortYieldProcessor

Prefetch_Addr:  DCD   Prefetch_Handler

Abort_Addr:     DCD   Abort_Handler

FIQ_Addr:       DCD   FIQ_Handler

/*

   Handles incoming interrupt requests by branching to the corresponding

   handler, as defined in the AIC. Supports interrupt nesting.

 */

irqHandler:

                portSAVE_CONTEXT

        /* Write in the IVR to support Protect Mode */

        LDR     lr, =AT91C_BASE_AIC

        LDR     r0, [r14, #AIC_IVR]

        STR     lr, [r14, #AIC_IVR]

        /* Branch to C portion of the interrupt handler */

        MOV     lr, pc

        BX      r0

        /* Acknowledge interrupt */

        LDR     lr, =AT91C_BASE_AIC

        STR     lr, [r14, #AIC_EOICR]

                portRESTORE_CONTEXT

/*

   After a reset, execution starts here, the mode is ARM, supervisor

   with interrupts disabled.

   Initializes the chip and branches to the main() function.

 */

        SECTION .cstartup:CODE:NOROOT(2)

        PUBLIC  resetHandler

        EXTERN  LowLevelInit

        EXTERN  ?main

        REQUIRE resetVector

        ARM

resetHandler:

        /* Set pc to actual code location (i.e. not in remap zone) */

            LDR     pc, =label

        /* Perform low-level initialization of the chip using LowLevelInit() */

label:

            LDR     r0, =LowLevelInit

        LDR     r4, =SFE(CSTACK)

        MOV     sp, r4

        MOV     lr, pc

        BX      r0

        /* Set up the interrupt stack pointer. */

        MSR     cpsr_c, #ARM_MODE_IRQ | I_BIT | F_BIT      ; Change the mode

        LDR     sp, =SFE(IRQ_STACK)

        /* Set up the SVC stack pointer. */

        MSR     cpsr_c, #ARM_MODE_SVC | F_BIT              ; Change the mode

        LDR     sp, =SFE(CSTACK)

        /* Branch to main() */

        LDR     r0, =?main

        MOV     lr, pc

        BX      r0

        /* Loop indefinitely when program is finished */

loop4:

        B       loop4

        END