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
|
/* ----------------------------------------------------------------------------
* 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.
* ----------------------------------------------------------------------------
*/
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include "board.h"
#include <pmc/pmc.h>
//------------------------------------------------------------------------------
// Internal definitions
//------------------------------------------------------------------------------
#define NORMAL_POWER_MODE 0
#define LOW_POWER_MODE 1
//------------------------------------------------------------------------------
// Internal variables
//------------------------------------------------------------------------------
static volatile unsigned char powerMode = NORMAL_POWER_MODE;
//------------------------------------------------------------------------------
// Internal functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
// Exported functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// Put the CPU in 32kHz, disable PLL, main oscillator
/// Put voltage regulator in standby mode
/// USB clock is automatically disabled.
//------------------------------------------------------------------------------
void LowPowerMode(void)
{
if (powerMode == LOW_POWER_MODE)
return;
powerMode = LOW_POWER_MODE;
// MCK=48MHz to MCK=32kHz
// MCK = SLCK/2 : change source first from 48 000 000 to 18. / 2 = 9M
AT91C_BASE_PMC->PMC_MCKR = AT91C_PMC_PRES_CLK_2;
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY ) );
// MCK=SLCK : then change prescaler
AT91C_BASE_PMC->PMC_MCKR = AT91C_PMC_CSS_SLOW_CLK;
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY ) );
// disable PLL
AT91C_BASE_PMC->PMC_PLLR = 0;
// Disable Main Oscillator
AT91C_BASE_PMC->PMC_MOR = 0;
// Voltage regulator in standby mode : Enable VREG Low Power Mode
AT91C_BASE_VREG->VREG_MR |= AT91C_VREG_PSTDBY;
PMC_DisableProcessorClock();
}
//------------------------------------------------------------------------------
/// Put voltage regulator in normal mode
/// Return the CPU to normal speed enable PLLs, main oscillator
/// USB clock is automatically enabled.
//------------------------------------------------------------------------------
void NormalPowerMode(void)
{
if (powerMode == NORMAL_POWER_MODE)
return;
// Voltage regulator in normal mode : Disable VREG Low Power Mode
AT91C_BASE_VREG->VREG_MR &= ~AT91C_VREG_PSTDBY;
// MCK=32kHz to MCK=48MHz
// enable Main Oscillator
AT91C_BASE_PMC->PMC_MOR = (( (AT91C_CKGR_OSCOUNT & (0x06 <<8)) | AT91C_CKGR_MOSCEN ));
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MOSCS ) );
// enable PLL@96MHz
AT91C_BASE_PMC->PMC_PLLR = ((AT91C_CKGR_DIV & 0x0E) |
(AT91C_CKGR_PLLCOUNT & (28<<8)) |
(AT91C_CKGR_MUL & (0x48<<16)));
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_LOCK ) );
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY ) );
AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1 ;
// MCK=SLCK/2 : change prescaler first
AT91C_BASE_PMC->PMC_MCKR = AT91C_PMC_PRES_CLK_2;
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY ) );
// MCK=PLLCK/2 : then change source
AT91C_BASE_PMC->PMC_MCKR |= AT91C_PMC_CSS_PLL_CLK ;
while( !( AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY ) );
powerMode = NORMAL_POWER_MODE;
}
|
