OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [rtos/] [freertos-6.1.1/] [Demo/] [RX600_RX62N-RDK_IAR/] [HighFrequencyTimerTest.c] - Blame information for rev 593

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 585 jeremybenn
/*
2
    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.
3
 
4
    ***************************************************************************
5
    *                                                                         *
6
    * If you are:                                                             *
7
    *                                                                         *
8
    *    + New to FreeRTOS,                                                   *
9
    *    + Wanting to learn FreeRTOS or multitasking in general quickly       *
10
    *    + Looking for basic training,                                        *
11
    *    + Wanting to improve your FreeRTOS skills and productivity           *
12
    *                                                                         *
13
    * then take a look at the FreeRTOS books - available as PDF or paperback  *
14
    *                                                                         *
15
    *        "Using the FreeRTOS Real Time Kernel - a Practical Guide"        *
16
    *                  http://www.FreeRTOS.org/Documentation                  *
17
    *                                                                         *
18
    * A pdf reference manual is also available.  Both are usually delivered   *
19
    * to your inbox within 20 minutes to two hours when purchased between 8am *
20
    * and 8pm GMT (although please allow up to 24 hours in case of            *
21
    * exceptional circumstances).  Thank you for your support!                *
22
    *                                                                         *
23
    ***************************************************************************
24
 
25
    This file is part of the FreeRTOS distribution.
26
 
27
    FreeRTOS is free software; you can redistribute it and/or modify it under
28
    the terms of the GNU General Public License (version 2) as published by the
29
    Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
30
    ***NOTE*** The exception to the GPL is included to allow you to distribute
31
    a combined work that includes FreeRTOS without being obliged to provide the
32
    source code for proprietary components outside of the FreeRTOS kernel.
33
    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT
34
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
35
    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
36
    more details. You should have received a copy of the GNU General Public
37
    License and the FreeRTOS license exception along with FreeRTOS; if not it
38
    can be viewed here: http://www.freertos.org/a00114.html and also obtained
39
    by writing to Richard Barry, contact details for whom are available on the
40
    FreeRTOS WEB site.
41
 
42
    1 tab == 4 spaces!
43
 
44
    http://www.FreeRTOS.org - Documentation, latest information, license and
45
    contact details.
46
 
47
    http://www.SafeRTOS.com - A version that is certified for use in safety
48
    critical systems.
49
 
50
    http://www.OpenRTOS.com - Commercial support, development, porting,
51
    licensing and training services.
52
*/
53
 
54
/*
55
 * High frequency timer test as described in main.c.
56
 */
57
 
58
/* Scheduler includes. */
59
#include "FreeRTOS.h"
60
 
61
/* Hardware specifics. */
62
#include <iorx62n.h>
63
 
64
/* The set frequency of the interrupt.  Deviations from this are measured as
65
the jitter. */
66
#define timerINTERRUPT_FREQUENCY                ( 20000UL )
67
 
68
/* The expected time between each of the timer interrupts - if the jitter was
69
zero. */
70
#define timerEXPECTED_DIFFERENCE_VALUE  ( ( unsigned short ) ( ( configPERIPHERAL_CLOCK_HZ / 8UL ) / timerINTERRUPT_FREQUENCY ) )
71
 
72
/* The highest available interrupt priority. */
73
#define timerHIGHEST_PRIORITY                   ( 15 )
74
 
75
/* Misc defines. */
76
#define timerTIMER_3_COUNT_VALUE                ( *( ( unsigned short * ) 0x8801a ) ) /*( CMT3.CMCNT )*/
77
 
78
/*-----------------------------------------------------------*/
79
 
80
/* Interrupt handler in which the jitter is measured. */
81
__interrupt void vTimer2IntHandler( void );
82
 
83
/* Stores the value of the maximum recorded jitter between interrupts. */
84
volatile unsigned short usMaxJitter = 0;
85
 
86
/* Counts the number of high frequency interrupts - used to generate the run
87
time stats. */
88
volatile unsigned long ulHighFrequencyTickCount = 0UL;
89
 
90
/*-----------------------------------------------------------*/
91
 
92
void vSetupHighFrequencyTimer( void )
93
{
94
        /* Timer CMT2 is used to generate the interrupts, and CMT3 is used
95
        to measure the jitter. */
96
 
97
        /* Enable compare match timer 2 and 3. */
98
        MSTP( CMT2 ) = 0;
99
        MSTP( CMT3 ) = 0;
100
 
101
        /* Interrupt on compare match. */
102
        CMT2.CMCR.BIT.CMIE = 1;
103
 
104
        /* Set the compare match value. */
105
        CMT2.CMCOR = ( unsigned short ) ( ( ( configPERIPHERAL_CLOCK_HZ / timerINTERRUPT_FREQUENCY ) -1 ) / 8 );
106
 
107
        /* Divide the PCLK by 8. */
108
        CMT2.CMCR.BIT.CKS = 0;
109
        CMT3.CMCR.BIT.CKS = 0;
110
 
111
        /* Enable the interrupt... */
112
        _IEN( _CMT2_CMI2 ) = 1;
113
 
114
        /* ...and set its priority to the maximum possible, this is above the priority
115
        set by configMAX_SYSCALL_INTERRUPT_PRIORITY so will nest. */
116
        _IPR( _CMT2_CMI2 ) = timerHIGHEST_PRIORITY;
117
 
118
        /* Start the timers. */
119
        CMT.CMSTR1.BIT.STR2 = 1;
120
        CMT.CMSTR1.BIT.STR3 = 1;
121
}
122
/*-----------------------------------------------------------*/
123
 
124
#pragma vector = VECT_CMT2_CMI2
125
__interrupt void vTimer2IntHandler( void )
126
{
127
volatile unsigned short usCurrentCount;
128
static unsigned short usMaxCount = 0;
129
static unsigned long ulErrorCount = 0UL;
130
 
131
        /* We use the timer 1 counter value to measure the clock cycles between
132
        the timer 0 interrupts.  First stop the clock. */
133
        CMT.CMSTR1.BIT.STR3 = 0;
134
        portNOP();
135
        portNOP();
136
        usCurrentCount = timerTIMER_3_COUNT_VALUE;
137
 
138
        /* Is this the largest count we have measured yet? */
139
        if( usCurrentCount > usMaxCount )
140
        {
141
                if( usCurrentCount > timerEXPECTED_DIFFERENCE_VALUE )
142
                {
143
                        usMaxJitter = usCurrentCount - timerEXPECTED_DIFFERENCE_VALUE;
144
                }
145
                else
146
                {
147
                        /* This should not happen! */
148
                        ulErrorCount++;
149
                }
150
 
151
                usMaxCount = usCurrentCount;
152
        }
153
 
154
        /* Used to generate the run time stats. */
155
        ulHighFrequencyTickCount++;
156
 
157
        /* Clear the timer. */
158
        timerTIMER_3_COUNT_VALUE = 0;
159
 
160
        /* Then start the clock again. */
161
        CMT.CMSTR1.BIT.STR3 = 1;
162
}
163
 
164
 
165
 
166
 
167
 
168
 
169
 

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.