Lee Kai Xuan / mbed-os

mbed-os

Fork of mbed-os by erkin yucel

targets/TARGET_STM/TARGET_STM32L1/pwmout_api.c@1:3deb71413561, 2017-07-20 (annotated)

Committer:
xuaner
Date:
Thu Jul 20 14:26:57 2017 +0000
Revision:
1:3deb71413561
Parent:
0:f269e3021894 
mbed_os

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elessair 0:f269e3021894 1 /* mbed Microcontroller Library
elessair 0:f269e3021894 2 *******************************************************************************
elessair 0:f269e3021894 3 * Copyright (c) 2014, STMicroelectronics
elessair 0:f269e3021894 4 * All rights reserved.
elessair 0:f269e3021894 5 *
elessair 0:f269e3021894 6 * Redistribution and use in source and binary forms, with or without
elessair 0:f269e3021894 7 * modification, are permitted provided that the following conditions are met:
elessair 0:f269e3021894 8 *
elessair 0:f269e3021894 9 * 1. Redistributions of source code must retain the above copyright notice,
elessair 0:f269e3021894 10 * this list of conditions and the following disclaimer.
elessair 0:f269e3021894 11 * 2. Redistributions in binary form must reproduce the above copyright notice,
elessair 0:f269e3021894 12 * this list of conditions and the following disclaimer in the documentation
elessair 0:f269e3021894 13 * and/or other materials provided with the distribution.
elessair 0:f269e3021894 14 * 3. Neither the name of STMicroelectronics nor the names of its contributors
elessair 0:f269e3021894 15 * may be used to endorse or promote products derived from this software
elessair 0:f269e3021894 16 * without specific prior written permission.
elessair 0:f269e3021894 17 *
elessair 0:f269e3021894 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
elessair 0:f269e3021894 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
elessair 0:f269e3021894 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
elessair 0:f269e3021894 21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
elessair 0:f269e3021894 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
elessair 0:f269e3021894 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
elessair 0:f269e3021894 24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
elessair 0:f269e3021894 25 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
elessair 0:f269e3021894 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
elessair 0:f269e3021894 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
elessair 0:f269e3021894 28 *******************************************************************************
elessair 0:f269e3021894 29 */
elessair 0:f269e3021894 30 #include "pwmout_api.h"
elessair 0:f269e3021894 31
elessair 0:f269e3021894 32 #if DEVICE_PWMOUT
elessair 0:f269e3021894 33
elessair 0:f269e3021894 34 #include "cmsis.h"
elessair 0:f269e3021894 35 #include "pinmap.h"
elessair 0:f269e3021894 36 #include "mbed_error.h"
elessair 0:f269e3021894 37 #include "PeripheralPins.h"
elessair 0:f269e3021894 38
elessair 0:f269e3021894 39 static TIM_HandleTypeDef TimHandle;
elessair 0:f269e3021894 40
elessair 0:f269e3021894 41 void pwmout_init(pwmout_t* obj, PinName pin)
elessair 0:f269e3021894 42 {
elessair 0:f269e3021894 43 // Get the peripheral name from the pin and assign it to the object
elessair 0:f269e3021894 44 obj->pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
elessair 0:f269e3021894 45
elessair 0:f269e3021894 46 if (obj->pwm == (PWMName)NC) {
elessair 0:f269e3021894 47 error("PWM error: pinout mapping failed.");
elessair 0:f269e3021894 48 }
elessair 0:f269e3021894 49
elessair 0:f269e3021894 50 // Enable TIM clock
elessair 0:f269e3021894 51 if (obj->pwm == PWM_2) __TIM2_CLK_ENABLE();
elessair 0:f269e3021894 52 if (obj->pwm == PWM_3) __TIM3_CLK_ENABLE();
elessair 0:f269e3021894 53 if (obj->pwm == PWM_4) __TIM4_CLK_ENABLE();
elessair 0:f269e3021894 54 if (obj->pwm == PWM_5) __TIM5_CLK_ENABLE();
elessair 0:f269e3021894 55 if (obj->pwm == PWM_9) __TIM9_CLK_ENABLE();
elessair 0:f269e3021894 56 if (obj->pwm == PWM_10) __TIM10_CLK_ENABLE();
elessair 0:f269e3021894 57 if (obj->pwm == PWM_11) __TIM11_CLK_ENABLE();
elessair 0:f269e3021894 58
elessair 0:f269e3021894 59 // Configure GPIO
elessair 0:f269e3021894 60 pinmap_pinout(pin, PinMap_PWM);
elessair 0:f269e3021894 61
elessair 0:f269e3021894 62 obj->pin = pin;
elessair 0:f269e3021894 63 obj->period = 0;
elessair 0:f269e3021894 64 obj->pulse = 0;
elessair 0:f269e3021894 65 obj->prescaler = 1;
elessair 0:f269e3021894 66
elessair 0:f269e3021894 67 pwmout_period_us(obj, 20000); // 20 ms per default
elessair 0:f269e3021894 68 }
elessair 0:f269e3021894 69
elessair 0:f269e3021894 70 void pwmout_free(pwmout_t* obj)
elessair 0:f269e3021894 71 {
elessair 0:f269e3021894 72 // Configure GPIO
elessair 0:f269e3021894 73 pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
elessair 0:f269e3021894 74 }
elessair 0:f269e3021894 75
elessair 0:f269e3021894 76 void pwmout_write(pwmout_t* obj, float value)
elessair 0:f269e3021894 77 {
elessair 0:f269e3021894 78 TIM_OC_InitTypeDef sConfig;
elessair 0:f269e3021894 79 int channel = 0;
elessair 0:f269e3021894 80
elessair 0:f269e3021894 81 TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
elessair 0:f269e3021894 82
elessair 0:f269e3021894 83 if (value < (float)0.0) {
elessair 0:f269e3021894 84 value = 0.0;
elessair 0:f269e3021894 85 } else if (value > (float)1.0) {
elessair 0:f269e3021894 86 value = 1.0;
elessair 0:f269e3021894 87 }
elessair 0:f269e3021894 88
elessair 0:f269e3021894 89 obj->pulse = (uint32_t)((float)obj->period * value);
elessair 0:f269e3021894 90
elessair 0:f269e3021894 91 // Configure channels
elessair 0:f269e3021894 92 sConfig.OCMode = TIM_OCMODE_PWM1;
elessair 0:f269e3021894 93 sConfig.Pulse = obj->pulse / obj->prescaler;
elessair 0:f269e3021894 94 sConfig.OCPolarity = TIM_OCPOLARITY_HIGH;
elessair 0:f269e3021894 95 sConfig.OCFastMode = TIM_OCFAST_ENABLE;
elessair 0:f269e3021894 96
elessair 0:f269e3021894 97 switch (obj->pin) {
elessair 0:f269e3021894 98 // Channels 1
elessair 0:f269e3021894 99 case PA_6:
elessair 0:f269e3021894 100 case PB_4:
elessair 0:f269e3021894 101 case PB_6:
elessair 0:f269e3021894 102 case PB_12:
elessair 0:f269e3021894 103 case PB_13:
elessair 0:f269e3021894 104 case PB_15:
elessair 0:f269e3021894 105 case PC_6:
elessair 0:f269e3021894 106 channel = TIM_CHANNEL_1;
elessair 0:f269e3021894 107 break;
elessair 0:f269e3021894 108 // Channels 2
elessair 0:f269e3021894 109 case PA_1:
elessair 0:f269e3021894 110 case PA_7:
elessair 0:f269e3021894 111 case PB_3:
elessair 0:f269e3021894 112 case PB_5:
elessair 0:f269e3021894 113 case PB_7:
elessair 0:f269e3021894 114 case PB_14:
elessair 0:f269e3021894 115 case PC_7:
elessair 0:f269e3021894 116 channel = TIM_CHANNEL_2;
elessair 0:f269e3021894 117 break;
elessair 0:f269e3021894 118 // Channels 3
elessair 0:f269e3021894 119 case PA_2:
elessair 0:f269e3021894 120 case PB_0:
elessair 0:f269e3021894 121 case PB_8:
elessair 0:f269e3021894 122 case PB_10:
elessair 0:f269e3021894 123 case PC_8:
elessair 0:f269e3021894 124 channel = TIM_CHANNEL_3;
elessair 0:f269e3021894 125 break;
elessair 0:f269e3021894 126 // Channels 4
elessair 0:f269e3021894 127 case PA_3:
elessair 0:f269e3021894 128 case PB_1:
elessair 0:f269e3021894 129 case PB_9:
elessair 0:f269e3021894 130 case PB_11:
elessair 0:f269e3021894 131 case PC_9:
elessair 0:f269e3021894 132 channel = TIM_CHANNEL_4;
elessair 0:f269e3021894 133 break;
elessair 0:f269e3021894 134 default:
elessair 0:f269e3021894 135 return;
elessair 0:f269e3021894 136 }
elessair 0:f269e3021894 137
elessair 0:f269e3021894 138 HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, channel);
elessair 0:f269e3021894 139 HAL_TIM_PWM_Start(&TimHandle, channel);
elessair 0:f269e3021894 140 }
elessair 0:f269e3021894 141
elessair 0:f269e3021894 142 float pwmout_read(pwmout_t* obj)
elessair 0:f269e3021894 143 {
elessair 0:f269e3021894 144 float value = 0;
elessair 0:f269e3021894 145 if (obj->period > 0) {
elessair 0:f269e3021894 146 value = (float)(obj->pulse) / (float)(obj->period);
elessair 0:f269e3021894 147 }
elessair 0:f269e3021894 148 return ((value > (float)1.0) ? (float)(1.0) : (value));
elessair 0:f269e3021894 149 }
elessair 0:f269e3021894 150
elessair 0:f269e3021894 151 void pwmout_period(pwmout_t* obj, float seconds)
elessair 0:f269e3021894 152 {
elessair 0:f269e3021894 153 pwmout_period_us(obj, seconds * 1000000.0f);
elessair 0:f269e3021894 154 }
elessair 0:f269e3021894 155
elessair 0:f269e3021894 156 void pwmout_period_ms(pwmout_t* obj, int ms)
elessair 0:f269e3021894 157 {
elessair 0:f269e3021894 158 pwmout_period_us(obj, ms * 1000);
elessair 0:f269e3021894 159 }
elessair 0:f269e3021894 160
elessair 0:f269e3021894 161 void pwmout_period_us(pwmout_t* obj, int us)
elessair 0:f269e3021894 162 {
elessair 0:f269e3021894 163 TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
elessair 0:f269e3021894 164
elessair 0:f269e3021894 165 float dc = pwmout_read(obj);
elessair 0:f269e3021894 166
elessair 0:f269e3021894 167 __HAL_TIM_DISABLE(&TimHandle);
elessair 0:f269e3021894 168
elessair 0:f269e3021894 169 /* To make it simple, we use to possible prescaler values which lead to:
elessair 0:f269e3021894 170 * pwm unit = 1us, period/pulse can be from 1us to 65535us
elessair 0:f269e3021894 171 * or
elessair 0:f269e3021894 172 * pwm unit = 500us, period/pulse can be from 500us to ~32.76sec
elessair 0:f269e3021894 173 * Be careful that all the channels of a PWM shares the same prescaler
elessair 0:f269e3021894 174 */
elessair 0:f269e3021894 175 if (us > 0xFFFF) {
elessair 0:f269e3021894 176 obj->prescaler = 500;
elessair 0:f269e3021894 177 } else {
elessair 0:f269e3021894 178 obj->prescaler = 1;
elessair 0:f269e3021894 179 }
elessair 0:f269e3021894 180 TimHandle.Init.Prescaler = ((SystemCoreClock / 1000000) * obj->prescaler) - 1;
elessair 0:f269e3021894 181
elessair 0:f269e3021894 182 if (TimHandle.Init.Prescaler > 0xFFFF)
elessair 0:f269e3021894 183 error("PWM: out of range prescaler");
elessair 0:f269e3021894 184
elessair 0:f269e3021894 185 TimHandle.Init.Period = (us - 1) / obj->prescaler;
elessair 0:f269e3021894 186 if (TimHandle.Init.Period > 0xFFFF)
elessair 0:f269e3021894 187 error("PWM: out of range period");
elessair 0:f269e3021894 188
elessair 0:f269e3021894 189 TimHandle.Init.ClockDivision = 0;
elessair 0:f269e3021894 190 TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
elessair 0:f269e3021894 191
elessair 0:f269e3021894 192 if (HAL_TIM_PWM_Init(&TimHandle) != HAL_OK) {
elessair 0:f269e3021894 193 error("Cannot initialize PWM");
elessair 0:f269e3021894 194 }
elessair 0:f269e3021894 195
elessair 0:f269e3021894 196 // Save for future use
elessair 0:f269e3021894 197 obj->period = us;
elessair 0:f269e3021894 198
elessair 0:f269e3021894 199 // Set duty cycle again
elessair 0:f269e3021894 200 pwmout_write(obj, dc);
elessair 0:f269e3021894 201
elessair 0:f269e3021894 202 __HAL_TIM_ENABLE(&TimHandle);
elessair 0:f269e3021894 203 }
elessair 0:f269e3021894 204
elessair 0:f269e3021894 205 void pwmout_pulsewidth(pwmout_t* obj, float seconds)
elessair 0:f269e3021894 206 {
elessair 0:f269e3021894 207 pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
elessair 0:f269e3021894 208 }
elessair 0:f269e3021894 209
elessair 0:f269e3021894 210 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms)
elessair 0:f269e3021894 211 {
elessair 0:f269e3021894 212 pwmout_pulsewidth_us(obj, ms * 1000);
elessair 0:f269e3021894 213 }
elessair 0:f269e3021894 214
elessair 0:f269e3021894 215 void pwmout_pulsewidth_us(pwmout_t* obj, int us)
elessair 0:f269e3021894 216 {
elessair 0:f269e3021894 217 float value = (float)us / (float)obj->period;
elessair 0:f269e3021894 218 pwmout_write(obj, value);
elessair 0:f269e3021894 219 }
elessair 0:f269e3021894 220
elessair 0:f269e3021894 221 #endif