erkin yucel / mbed-os

mbed os with nrf51 internal bandgap enabled to read battery level

Dependents:   BLE_file_test BLE_Blink ExternalEncoder

targets/TARGET_STM/TARGET_STM32L0/pwmout_api.c@0:f269e3021894, 2016-10-23 (annotated)

Committer:
elessair
Date:
Sun Oct 23 15:10:02 2016 +0000
Revision:
0:f269e3021894
Initial commit

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) 2015, 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 MBED_ASSERT(obj->pwm != (PWMName)NC);
elessair 0:f269e3021894 46
elessair 0:f269e3021894 47 // Get the pin function and assign the used channel to the object
elessair 0:f269e3021894 48 uint32_t function = pinmap_function(pin, PinMap_PWM);
elessair 0:f269e3021894 49 MBED_ASSERT(function != (uint32_t)NC);
elessair 0:f269e3021894 50 obj->channel = STM_PIN_CHANNEL(function);
elessair 0:f269e3021894 51 obj->inverted = STM_PIN_INVERTED(function);
elessair 0:f269e3021894 52
elessair 0:f269e3021894 53 // Enable TIM clock
elessair 0:f269e3021894 54 if (obj->pwm == PWM_2) __TIM2_CLK_ENABLE();
elessair 0:f269e3021894 55 #if defined(TIM3_BASE)
elessair 0:f269e3021894 56 if (obj->pwm == PWM_3) __TIM3_CLK_ENABLE();
elessair 0:f269e3021894 57 #endif
elessair 0:f269e3021894 58 if (obj->pwm == PWM_21) __TIM21_CLK_ENABLE();
elessair 0:f269e3021894 59 #if defined(TIM22_BASE)
elessair 0:f269e3021894 60 if (obj->pwm == PWM_22) __TIM22_CLK_ENABLE();
elessair 0:f269e3021894 61 #endif
elessair 0:f269e3021894 62
elessair 0:f269e3021894 63 // Configure GPIO
elessair 0:f269e3021894 64 pinmap_pinout(pin, PinMap_PWM);
elessair 0:f269e3021894 65
elessair 0:f269e3021894 66 obj->pin = pin;
elessair 0:f269e3021894 67 obj->period = 0;
elessair 0:f269e3021894 68 obj->pulse = 0;
elessair 0:f269e3021894 69 obj->prescaler = 1;
elessair 0:f269e3021894 70
elessair 0:f269e3021894 71 pwmout_period_us(obj, 20000); // 20 ms per default
elessair 0:f269e3021894 72 }
elessair 0:f269e3021894 73
elessair 0:f269e3021894 74 void pwmout_free(pwmout_t* obj)
elessair 0:f269e3021894 75 {
elessair 0:f269e3021894 76 // Configure GPIO
elessair 0:f269e3021894 77 pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
elessair 0:f269e3021894 78 }
elessair 0:f269e3021894 79
elessair 0:f269e3021894 80 void pwmout_write(pwmout_t* obj, float value)
elessair 0:f269e3021894 81 {
elessair 0:f269e3021894 82 TIM_OC_InitTypeDef sConfig;
elessair 0:f269e3021894 83 int channel = 0;
elessair 0:f269e3021894 84
elessair 0:f269e3021894 85 TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
elessair 0:f269e3021894 86
elessair 0:f269e3021894 87 if (value < (float)0.0) {
elessair 0:f269e3021894 88 value = 0.0;
elessair 0:f269e3021894 89 } else if (value > (float)1.0) {
elessair 0:f269e3021894 90 value = 1.0;
elessair 0:f269e3021894 91 }
elessair 0:f269e3021894 92
elessair 0:f269e3021894 93 obj->pulse = (uint32_t)((float)obj->period * value);
elessair 0:f269e3021894 94
elessair 0:f269e3021894 95 // Configure channels
elessair 0:f269e3021894 96 sConfig.OCMode = TIM_OCMODE_PWM1;
elessair 0:f269e3021894 97 sConfig.Pulse = obj->pulse / obj->prescaler;
elessair 0:f269e3021894 98 sConfig.OCPolarity = TIM_OCPOLARITY_HIGH;
elessair 0:f269e3021894 99 sConfig.OCFastMode = TIM_OCFAST_ENABLE;
elessair 0:f269e3021894 100
elessair 0:f269e3021894 101 switch (obj->channel) {
elessair 0:f269e3021894 102 case 1:
elessair 0:f269e3021894 103 channel = TIM_CHANNEL_1;
elessair 0:f269e3021894 104 break;
elessair 0:f269e3021894 105 case 2:
elessair 0:f269e3021894 106 channel = TIM_CHANNEL_2;
elessair 0:f269e3021894 107 break;
elessair 0:f269e3021894 108 case 3:
elessair 0:f269e3021894 109 channel = TIM_CHANNEL_3;
elessair 0:f269e3021894 110 break;
elessair 0:f269e3021894 111 case 4:
elessair 0:f269e3021894 112 channel = TIM_CHANNEL_4;
elessair 0:f269e3021894 113 break;
elessair 0:f269e3021894 114 default:
elessair 0:f269e3021894 115 return;
elessair 0:f269e3021894 116 }
elessair 0:f269e3021894 117
elessair 0:f269e3021894 118 if (HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, channel) != HAL_OK) {
elessair 0:f269e3021894 119 error("Cannot initialize PWM");
elessair 0:f269e3021894 120 }
elessair 0:f269e3021894 121
elessair 0:f269e3021894 122 HAL_TIM_PWM_Start(&TimHandle, channel);
elessair 0:f269e3021894 123 }
elessair 0:f269e3021894 124
elessair 0:f269e3021894 125 float pwmout_read(pwmout_t* obj)
elessair 0:f269e3021894 126 {
elessair 0:f269e3021894 127 float value = 0;
elessair 0:f269e3021894 128 if (obj->period > 0) {
elessair 0:f269e3021894 129 value = (float)(obj->pulse) / (float)(obj->period);
elessair 0:f269e3021894 130 }
elessair 0:f269e3021894 131 return ((value > (float)1.0) ? (float)(1.0) : (value));
elessair 0:f269e3021894 132 }
elessair 0:f269e3021894 133
elessair 0:f269e3021894 134 void pwmout_period(pwmout_t* obj, float seconds)
elessair 0:f269e3021894 135 {
elessair 0:f269e3021894 136 pwmout_period_us(obj, seconds * 1000000.0f);
elessair 0:f269e3021894 137 }
elessair 0:f269e3021894 138
elessair 0:f269e3021894 139 void pwmout_period_ms(pwmout_t* obj, int ms)
elessair 0:f269e3021894 140 {
elessair 0:f269e3021894 141 pwmout_period_us(obj, ms * 1000);
elessair 0:f269e3021894 142 }
elessair 0:f269e3021894 143
elessair 0:f269e3021894 144 void pwmout_period_us(pwmout_t* obj, int us)
elessair 0:f269e3021894 145 {
elessair 0:f269e3021894 146 TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
elessair 0:f269e3021894 147
elessair 0:f269e3021894 148 float dc = pwmout_read(obj);
elessair 0:f269e3021894 149
elessair 0:f269e3021894 150 __HAL_TIM_DISABLE(&TimHandle);
elessair 0:f269e3021894 151
elessair 0:f269e3021894 152 /* To make it simple, we use to possible prescaler values which lead to:
elessair 0:f269e3021894 153 * pwm unit = 1us, period/pulse can be from 1us to 65535us
elessair 0:f269e3021894 154 * or
elessair 0:f269e3021894 155 * pwm unit = 500us, period/pulse can be from 500us to ~32.76sec
elessair 0:f269e3021894 156 * Be careful that all the channels of a PWM shares the same prescaler
elessair 0:f269e3021894 157 */
elessair 0:f269e3021894 158 if (us > 0xFFFF) {
elessair 0:f269e3021894 159 obj->prescaler = 500;
elessair 0:f269e3021894 160 } else {
elessair 0:f269e3021894 161 obj->prescaler = 1;
elessair 0:f269e3021894 162 }
elessair 0:f269e3021894 163 TimHandle.Init.Prescaler = ((SystemCoreClock / 1000000) * obj->prescaler) - 1;
elessair 0:f269e3021894 164
elessair 0:f269e3021894 165 if (TimHandle.Init.Prescaler > 0xFFFF)
elessair 0:f269e3021894 166 error("PWM: out of range prescaler");
elessair 0:f269e3021894 167
elessair 0:f269e3021894 168 TimHandle.Init.Period = (us - 1) / obj->prescaler;
elessair 0:f269e3021894 169 if (TimHandle.Init.Period > 0xFFFF)
elessair 0:f269e3021894 170 error("PWM: out of range period");
elessair 0:f269e3021894 171
elessair 0:f269e3021894 172 TimHandle.Init.ClockDivision = 0;
elessair 0:f269e3021894 173 TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
elessair 0:f269e3021894 174
elessair 0:f269e3021894 175 if (HAL_TIM_PWM_Init(&TimHandle) != HAL_OK) {
elessair 0:f269e3021894 176 error("Cannot initialize PWM");
elessair 0:f269e3021894 177 }
elessair 0:f269e3021894 178
elessair 0:f269e3021894 179 // Save for future use
elessair 0:f269e3021894 180 obj->period = us;
elessair 0:f269e3021894 181
elessair 0:f269e3021894 182 // Set duty cycle again
elessair 0:f269e3021894 183 pwmout_write(obj, dc);
elessair 0:f269e3021894 184
elessair 0:f269e3021894 185 __HAL_TIM_ENABLE(&TimHandle);
elessair 0:f269e3021894 186 }
elessair 0:f269e3021894 187
elessair 0:f269e3021894 188 void pwmout_pulsewidth(pwmout_t* obj, float seconds)
elessair 0:f269e3021894 189 {
elessair 0:f269e3021894 190 pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
elessair 0:f269e3021894 191 }
elessair 0:f269e3021894 192
elessair 0:f269e3021894 193 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms)
elessair 0:f269e3021894 194 {
elessair 0:f269e3021894 195 pwmout_pulsewidth_us(obj, ms * 1000);
elessair 0:f269e3021894 196 }
elessair 0:f269e3021894 197
elessair 0:f269e3021894 198 void pwmout_pulsewidth_us(pwmout_t* obj, int us)
elessair 0:f269e3021894 199 {
elessair 0:f269e3021894 200 float value = (float)us / (float)obj->period;
elessair 0:f269e3021894 201 pwmout_write(obj, value);
elessair 0:f269e3021894 202 }
elessair 0:f269e3021894 203
elessair 0:f269e3021894 204 #endif