summaryrefslogtreecommitdiff
path: root/FreeRTOS/Demo/PIC18_MPLAB/main2.c
blob: 3fae592ca2cf6dd68ffaef79957f3de45a2456a0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
/*
    FreeRTOS V8.0.0:rc1 - Copyright (C) 2014 Real Time Engineers Ltd.
    All rights reserved

    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    ***************************************************************************
     *                                                                       *
     *    FreeRTOS provides completely free yet professionally developed,    *
     *    robust, strictly quality controlled, supported, and cross          *
     *    platform software that has become a de facto standard.             *
     *                                                                       *
     *    Help yourself get started quickly and support the FreeRTOS         *
     *    project by purchasing a FreeRTOS tutorial book, reference          *
     *    manual, or both from: http://www.FreeRTOS.org/Documentation        *
     *                                                                       *
     *    Thank you!                                                         *
     *                                                                       *
    ***************************************************************************

    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.  Full license text is available from the following
    link: http://www.freertos.org/a00114.html

    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, books, training, latest versions,
    license and Real Time Engineers Ltd. contact details.

    http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
    including FreeRTOS+Trace - an indispensable productivity tool, a DOS
    compatible FAT file system, and our tiny thread aware UDP/IP stack.

    http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
    Integrity Systems to sell under the OpenRTOS brand.  Low cost OpenRTOS
    licenses offer ticketed support, indemnification and middleware.

    http://www.SafeRTOS.com - High Integrity Systems also provide a safety
    engineered and independently SIL3 certified version for use in safety and
    mission critical applications that require provable dependability.

    1 tab == 4 spaces!
*/

/*
 * Instead of the normal single demo application, the PIC18F demo is split
 * into several smaller programs of which this is the second.  This enables the
 * demo's to be executed on the RAM limited 40 pin devices.  The 64 and 80 pin
 * devices require a more costly development platform and are not so readily
 * available.
 *
 * The RTOSDemo2 project is configured for a PIC18F452 device.  Main2.c starts
 * 5 tasks (including the idle task).
 *
 * The first, second and third tasks do nothing but flash an LED.  This gives
 * visual feedback that everything is executing as expected.  One task flashes
 * an LED every 333ms (i.e. on and off every 333/2 ms), then next every 666ms
 * and the last every 999ms.
 *
 * The last task runs at the idle priority.  It repeatedly performs a 32bit
 * calculation and checks it's result against the expected value.  This checks
 * that the temporary storage utilised by the compiler to hold intermediate
 * results does not get corrupted when the task gets switched in and out.
 * should the calculation ever provide an incorrect result the final LED is
 * turned on.
 *
 * On entry to main() an 'X' is transmitted.  Monitoring the serial port using a
 * dumb terminal allows for verification that the device is not continuously
 * being reset (no more than one 'X' should be transmitted).
 *
 * http://www.FreeRTOS.org contains important information on the use of the
 * PIC18F port.
 */

/*
Changes from V2.0.0

	+ Delay periods are now specified using variables and constants of
	  TickType_t rather than unsigned long.
*/

/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"

/* Demo app include files. */
#include "flash.h"
#include "partest.h"
#include "serial.h"

/* Priority definitions for the LED tasks.  Other tasks just use the idle
priority. */
#define mainLED_FLASH_PRIORITY			( tskIDLE_PRIORITY + ( unsigned portBASE_TYPE ) 1 )

/* The LED that is lit when should the calculation fail. */
#define mainCHECK_TASK_LED				( ( unsigned portBASE_TYPE ) 3 )

/* Constants required for the communications.  Only one character is ever
transmitted. */
#define mainCOMMS_QUEUE_LENGTH			( ( unsigned portBASE_TYPE ) 5 )
#define mainNO_BLOCK					( ( TickType_t ) 0 )
#define mainBAUD_RATE					( ( unsigned long ) 9600 )

/*
 * The task that performs the 32 bit calculation at the idle priority.
 */
static void vCalculationTask( void *pvParameters );

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

/* Creates the tasks, then starts the scheduler. */
void main( void )
{
	/* Initialise the required hardware. */
	vParTestInitialise();
	vPortInitialiseBlocks();

	/* Send a character so we have some visible feedback of a reset. */
	xSerialPortInitMinimal( mainBAUD_RATE, mainCOMMS_QUEUE_LENGTH );
	xSerialPutChar( NULL, 'X', mainNO_BLOCK );

	/* Start the standard LED flash tasks as defined in demo/common/minimal. */
	vStartLEDFlashTasks( mainLED_FLASH_PRIORITY );

	/* Start the check task defined in this file. */
	xTaskCreate( vCalculationTask, "Check", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );

	/* Start the scheduler. */
	vTaskStartScheduler();
}
/*-----------------------------------------------------------*/

static void vCalculationTask( void *pvParameters )
{
volatile unsigned long ulCalculatedValue; /* Volatile to ensure optimisation is minimal. */

	/* Continuously perform a calculation.  If the calculation result is ever
	incorrect turn the LED on. */
	for( ;; )
	{
		/* A good optimising compiler would just remove all this! */
		ulCalculatedValue = 1234UL;
		ulCalculatedValue *= 99UL;

		if( ulCalculatedValue != 122166UL )
		{
			vParTestSetLED( mainCHECK_TASK_LED, pdTRUE );
		}

		ulCalculatedValue *= 9876UL;

		if( ulCalculatedValue != 1206511416UL )
		{
			vParTestSetLED( mainCHECK_TASK_LED, pdTRUE );
		}

		ulCalculatedValue /= 15UL;

		if( ulCalculatedValue != 80434094UL )
		{
			vParTestSetLED( mainCHECK_TASK_LED, pdTRUE );
		}

		ulCalculatedValue += 918273UL;

		if( ulCalculatedValue != 81352367UL )
		{
			vParTestSetLED( mainCHECK_TASK_LED, pdTRUE );
		}
	}
}
/*-----------------------------------------------------------*/