[修改] 增加freeRTOS

1. 版本FreeRTOSv202212.01，命名为kernel；

kernel/FreeRTOS/Demo/PIC32MZ_MPLAB/IntQueueTimer.c

@@ -0,0 +1,97 @@
+/*
+ * FreeRTOS V202212.01
+ * 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.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+#include "FreeRTOS.h"
+#include "IntQueueTimer.h"
+#include "IntQueue.h"
+
+#define timerINTERRUPT3_FREQUENCY	( 2000UL )
+#define timerINTERRUPT4_FREQUENCY	( 2001UL )
+
+void vT3InterruptHandler( void );
+void vT4InterruptHandler( void );
+
+/* As these interrupts use the FreeRTOS interrupt entry point, the IPL settings
+in the following prototypes have no effect.  The interrupt priorities are set
+by the ConfigIntTimerX() library calls in vInitialiseTimerForIntQueueTest(). */
+void __attribute__( (interrupt(IPL0AUTO), vector(_TIMER_3_VECTOR))) vT3InterruptWrapper( void );
+void __attribute__( (interrupt(IPL0AUTO), vector(_TIMER_4_VECTOR))) vT4InterruptWrapper( void );
+
+void vInitialiseTimerForIntQueueTest( void )
+{
+	/* Timer 1 is used for the tick interrupt, timer 2 is used for the high
+	frequency interrupt test.  This file therefore uses timers 3 and 4. */
+
+	T3CON = 0;
+	TMR3 = 0;
+	PR3 = ( unsigned short ) ( configPERIPHERAL_CLOCK_HZ / timerINTERRUPT3_FREQUENCY );
+
+	/* Setup timer 3 interrupt priority to be above the kernel priority. */
+	IPC3bits.T3IP = ( configMAX_SYSCALL_INTERRUPT_PRIORITY - 1 );
+
+	/* Clear the interrupt as a starting condition. */
+	IFS0bits.T3IF = 0;
+
+	/* Enable the interrupt. */
+	IEC0bits.T3IE = 1;
+
+	/* Start the timer. */
+	T3CONbits.TON = 1;
+
+
+	/* Do the same for timer 4. */
+	T4CON = 0;
+	TMR4 = 0;
+	PR4 = ( unsigned short ) ( configPERIPHERAL_CLOCK_HZ / timerINTERRUPT4_FREQUENCY );
+
+	/* Setup timer 4 interrupt priority to be above the kernel priority. */
+	IPC4bits.T4IP = configMAX_SYSCALL_INTERRUPT_PRIORITY;
+
+	/* Clear the interrupt as a starting condition. */
+	IFS0bits.T4IF = 0;
+
+	/* Enable the interrupt. */
+	IEC0bits.T4IE = 1;
+
+	/* Start the timer. */
+	T4CONbits.TON = 1;
+}
+/*-----------------------------------------------------------*/
+
+void vT3InterruptHandler( void )
+{
+	IFS0CLR = _IFS0_T3IF_MASK;
+	portEND_SWITCHING_ISR( xFirstTimerHandler() );
+}
+/*-----------------------------------------------------------*/
+
+void vT4InterruptHandler( void )
+{
+	IFS0CLR = _IFS0_T4IF_MASK;
+	portEND_SWITCHING_ISR( xSecondTimerHandler() );
+}
+
+