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;/*
; * FreeRTOS Kernel V10.3.0
; * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
; *
; * Permission is hereby granted, free of charge, to any person obtaining a copy of
; * this software and associated documentation files (the "Software"), to deal in
; * the Software without restriction, including without limitation the rights to
; * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
; * the Software, and to permit persons to whom the Software is furnished to do so,
; * subject to the following conditions:
; *
; * The above copyright notice and this permission notice shall be included in all
; * copies or substantial portions of the Software.
; *
; * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
; * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
; * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
; * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
; * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
; * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
; *
; * http://www.FreeRTOS.org
; * http://aws.amazon.com/freertos
; *
; * 1 tab == 4 spaces!
; */
;*
; * This file defines the assembler wrapper for the example interrupt that is
; * defined in main.c. The wrapper is the interrupt entry point.
; *
; ISR_Support.h contains the definitions of portSAVE_CONTEXT() and
; portRESTORE_CONTEXT().
#include "ISR_Support.h"
PUBLIC vANExampleISR_ASM_Wrapper
EXTERN vAnExampleISR_C_Handler
RSEG CODE:CODE
; *
; * This demo does not include a functional interrupt service routine - so
; * this dummy handler (which is not actually installed) is provided as an
; * example of how an ISR that needs to cause a context switch needs to be
; * implemented. ISRs that do not cause a context switch have no special
; * requirements and can be written as per the compiler documentation.
; *
; * This assembly wrapper function calls the main handler, which is called
; * vAnExampleISR_C_Handler(), and is implemented in main.c. See the
; * documentation page for this demo on the FreeRTOS.org website for full
; * instructions.
; *
; * NOTE: vANExampleISR_ASM_Wrapper needs to be installed into the relevant
; * vector, an example of how to do this from an assembly file is locate at
; * the bottom of this file.
; *
vANExampleISR_ASM_Wrapper:
; portSAVE_CONTEXT() must be the first thing called in the ASM
; wrapper.
portSAVE_CONTEXT
; Once the context has been saved the C handler can be called.
call !!vAnExampleISR_C_Handler
; Finally the ISR must end with a call to portRESTORE_CONTEXT()
; followed by a reti instruction to return from the interrupt to whichever
; task is now the task selected to run (which may be different to the task
; that was running before the interrupt started).
portRESTORE_CONTEXT
reti
; The interrupt handler can be installed into the vector table in the same
; assembly file.
; Ensure the vector table segement is used.
COMMON INTVEC:CODE:ROOT(1)
;
; Place a pointer to the asm wrapper at the correct index into the vector
; table. Note 56 is used is purely as an example. The correct vector
; number for the interrupt being installed must be used.
ORG 58
DW vANExampleISR_ASM_Wrapper
END
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