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
|
/******************************************************************************
* The MIT License
*
* Copyright (c) 2010 Michael Hope.
*
* 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.
*****************************************************************************/
/**
* @file iwdg.h
* @author Michael Hope, Marti Bolivar <mbolivar@leaflabs.com>
* @brief Independent watchdog support.
*
* To use the independent watchdog, first call iwdg_init() with the
* appropriate prescaler and IWDG counter reload values for your
* application. Afterwards, you must periodically call iwdg_feed()
* before the IWDG counter reaches 0 to reset the counter to its
* reload value. If you do not, the chip will reset.
*
* Once started, the independent watchdog cannot be turned off.
*/
#ifndef _IWDG_H_
#define _IWDG_H_
#include "libmaple_types.h"
#include "util.h"
#ifdef __cplusplus
extern "C"{
#endif
/*
* Register map
*/
/** Independent watchdog register map type. */
typedef struct iwdg_reg_map {
__io uint32 KR; /**< Key register. */
__io uint32 PR; /**< Prescaler register. */
__io uint32 RLR; /**< Reload register. */
__io uint32 SR; /**< Status register */
} iwdg_reg_map;
#define IWDG_BASE ((struct iwdg_reg_map*)0x40003000)
/*
* Register bit definitions
*/
/* Key register */
#define IWDG_KR_UNLOCK 0x5555
#define IWDG_KR_FEED 0xAAAA
#define IWDG_KR_START 0xCCCC
/* Prescaler register */
#define IWDG_PR_DIV_4 0x0
#define IWDG_PR_DIV_8 0x1
#define IWDG_PR_DIV_16 0x2
#define IWDG_PR_DIV_32 0x3
#define IWDG_PR_DIV_64 0x4
#define IWDG_PR_DIV_128 0x5
#define IWDG_PR_DIV_256 0x6
/* Status register */
#define IWDG_SR_RVU_BIT 1
#define IWDG_SR_PVU_BIT 0
#define IWDG_SR_RVU BIT(IWDG_SR_RVU_BIT)
#define IWDG_SR_PVU BIT(IWDG_SR_PVU_BIT)
/** Independent watchdog prescalers */
typedef enum {
IWDG_PRE_4 = IWDG_PR_DIV_4,
IWDG_PRE_8 = IWDG_PR_DIV_8,
IWDG_PRE_16 = IWDG_PR_DIV_16,
IWDG_PRE_32 = IWDG_PR_DIV_32,
IWDG_PRE_64 = IWDG_PR_DIV_64,
IWDG_PRE_128 = IWDG_PR_DIV_128,
IWDG_PRE_256 = IWDG_PR_DIV_256
} iwdg_prescaler;
void iwdg_init(iwdg_prescaler prescaler, uint16 reload);
void iwdg_feed(void);
#ifdef __cplusplus
} // extern "C"
#endif
#endif
|
