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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
|
/*
ChibiOS/HAL - Copyright (C) 2018 Andru
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
/**
* @file hal_pwm_lld.h
* @brief NRF52 PWM subsystem low level driver header.
*
* @addtogroup PWM
* @{
*/
#ifndef HAL_PWM_LLD_H_
#define HAL_PWM_LLD_H_
#if HAL_USE_PWM || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver constants. */
/*===========================================================================*/
/**
* @brief Number of PWM channels per PWM driver.
*/
#define PWM_CHANNELS 4
typedef enum {
PWM_FREQUENCY_16MHZ = 16000000, /** @brief 16MHz */
PWM_FREQUENCY_8MHZ = 8000000, /** @brief 8MHz */
PWM_FREQUENCY_4MHZ = 4000000, /** @brief 4MHz */
PWM_FREQUENCY_2MHZ = 2000000, /** @brief 2MHz */
PWM_FREQUENCY_1MHZ = 1000000, /** @brief 1MHz */
PWM_FREQUENCY_500KHZ = 500000, /** @brief 500kHz */
PWM_FREQUENCY_250KHZ = 250000, /** @brief 250kHz */
PWM_FREQUENCY_125KHZ = 125000, /** @brief 125kHz */
} pwm_frequency_t;
/*===========================================================================*/
/* Driver pre-compile time settings. */
/*===========================================================================*/
/**
* @name Configuration options
* @{
*/
/** @} */
/*===========================================================================*/
/* Configuration checks. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver data structures and types. */
/*===========================================================================*/
/**
* @brief Type of a PWM mode.
*/
typedef uint32_t pwmmode_t;
/**
* @brief Type of a PWM channel.
*/
typedef uint8_t pwmchannel_t;
/**
* @brief Type of a channels mask.
*/
typedef uint32_t pwmchnmsk_t;
/**
* @brief Type of a PWM counter.
*/
typedef uint16_t pwmcnt_t;
/**
* @brief Type of a PWM driver channel configuration structure.
*/
typedef struct {
/**
* @brief Channel active logic level.
*/
pwmmode_t mode;
/**
* @brief Channel callback pointer.
* @note This callback is invoked on the channel compare event. If set to
* @p NULL then the callback is disabled.
*/
pwmcallback_t callback;
/* End of the mandatory fields.*/
/**
* @brief PAL line to toggle.
* @note Only used if mode is PWM_OUTPUT_HIGH or PWM_OUTPUT_LOW.
* @note When channel enabled it wont be possible to access this PAL line using the PAL
* driver.
*/
ioline_t ioline;
} PWMChannelConfig;
/**
* @brief Type of a PWM driver configuration structure.
*/
typedef struct {
/**
* @brief Timer clock in Hz.
* @note The low level can use assertions in order to catch invalid
* frequency specifications.
*/
pwm_frequency_t frequency;
/**
* @brief PWM period in ticks.
* @note The low level can use assertions in order to catch invalid
* period specifications.
*/
pwmcnt_t period;
/**
* @brief Periodic callback pointer.
* @note This callback is invoked on PWM counter reset. If set to
* @p NULL then the callback is disabled.
*/
pwmcallback_t callback;
/**
* @brief Channels configurations.
*/
PWMChannelConfig channels[PWM_CHANNELS];
/* End of the mandatory fields.*/
} PWMConfig;
/**
* @brief Structure representing a PWM driver.
*/
struct PWMDriver {
/**
* @brief Driver state.
*/
pwmstate_t state;
/**
* @brief Current driver configuration data.
*/
const PWMConfig *config;
/**
* @brief Current PWM period in ticks.
*/
pwmcnt_t period;
/**
* @brief Mask of the enabled channels.
*/
pwmchnmsk_t enabled;
/**
* @brief Number of channels in this instance.
*/
pwmchannel_t channels;
#if defined(PWM_DRIVER_EXT_FIELDS)
PWM_DRIVER_EXT_FIELDS
#endif
/* End of the mandatory fields.*/
/**
* @brief Pointer to the PWM registers block.
*/
NRF_PWM_Type *pwm;
};
/*===========================================================================*/
/* Driver macros. */
/*===========================================================================*/
/**
* @brief Changes the period the PWM peripheral.
* @details This function changes the period of a PWM unit that has already
* been activated using @p pwmStart().
* @pre The PWM unit must have been activated using @p pwmStart().
* @post The PWM unit period is changed to the new value.
* @note The function has effect at the next cycle start.
* @note If a period is specified that is shorter than the pulse width
* programmed in one of the channels then the behavior is not
* guaranteed.
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] period new cycle time in ticks
*
* @notapi
*/
#define pwm_lld_change_period(pwmp, period) \
do { \
(pwmp)->pwm->COUNTERTOP = period & PWM_COUNTERTOP_COUNTERTOP_Msk; \
} while(0)
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#if NRF5_PWM_USE_PWM0 || defined(__DOXYGEN__)
extern PWMDriver PWMD1;
#endif
#if NRF5_PWM_USE_PWM1 || defined(__DOXYGEN__)
extern PWMDriver PWMD2;
#endif
#if NRF5_PWM_USE_PWM2 || defined(__DOXYGEN__)
extern PWMDriver PWMD3;
#endif
#ifdef __cplusplus
extern "C" {
#endif
void pwm_lld_init(void);
void pwm_lld_start(PWMDriver *pwmp);
void pwm_lld_stop(PWMDriver *pwmp);
void pwm_lld_enable_channel(PWMDriver *pwmp,
pwmchannel_t channel,
pwmcnt_t width);
void pwm_lld_disable_channel(PWMDriver *pwmp, pwmchannel_t channel);
void pwm_lld_enable_periodic_notification(PWMDriver *pwmp);
void pwm_lld_disable_periodic_notification(PWMDriver *pwmp);
void pwm_lld_enable_channel_notification(PWMDriver *pwmp,
pwmchannel_t channel);
void pwm_lld_disable_channel_notification(PWMDriver *pwmp,
pwmchannel_t channel);
#ifdef __cplusplus
}
#endif
#endif /* HAL_USE_PWM */
#endif /* HAL_PWM_LLD_H_ */
/** @} */
|
