mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

Dependents:   Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more

targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/pwmout_api.c@144:ef7eb2e8f9f7, 2016-09-02 (annotated)

Committer:
<>
Date:
Fri Sep 02 15:07:44 2016 +0100
Revision:
144:ef7eb2e8f9f7
Parent:
50:a417edff4437 
This updates the lib to the mbed lib v125

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /***************************************************************************//**
<> 144:ef7eb2e8f9f7 2 * @file pwmout_api.c
<> 144:ef7eb2e8f9f7 3 *******************************************************************************
<> 144:ef7eb2e8f9f7 4 * @section License
<> 144:ef7eb2e8f9f7 5 * <b>(C) Copyright 2015 Silicon Labs, http://www.silabs.com</b>
<> 144:ef7eb2e8f9f7 6 *******************************************************************************
<> 144:ef7eb2e8f9f7 7 *
<> 144:ef7eb2e8f9f7 8 * SPDX-License-Identifier: Apache-2.0
<> 144:ef7eb2e8f9f7 9 *
<> 144:ef7eb2e8f9f7 10 * Licensed under the Apache License, Version 2.0 (the "License"); you may
<> 144:ef7eb2e8f9f7 11 * not use this file except in compliance with the License.
<> 144:ef7eb2e8f9f7 12 * You may obtain a copy of the License at
<> 144:ef7eb2e8f9f7 13 *
<> 144:ef7eb2e8f9f7 14 * http://www.apache.org/licenses/LICENSE-2.0
<> 144:ef7eb2e8f9f7 15 *
<> 144:ef7eb2e8f9f7 16 * Unless required by applicable law or agreed to in writing, software
<> 144:ef7eb2e8f9f7 17 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
<> 144:ef7eb2e8f9f7 18 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 144:ef7eb2e8f9f7 19 * See the License for the specific language governing permissions and
<> 144:ef7eb2e8f9f7 20 * limitations under the License.
<> 144:ef7eb2e8f9f7 21 *
<> 144:ef7eb2e8f9f7 22 ******************************************************************************/
<> 144:ef7eb2e8f9f7 23
<> 144:ef7eb2e8f9f7 24 #include "device.h"
<> 144:ef7eb2e8f9f7 25 #include "clocking.h"
<> 144:ef7eb2e8f9f7 26 #if DEVICE_PWMOUT
<> 144:ef7eb2e8f9f7 27
<> 144:ef7eb2e8f9f7 28 #include "mbed_assert.h"
<> 144:ef7eb2e8f9f7 29 #include "pwmout_api.h"
<> 144:ef7eb2e8f9f7 30 #include "cmsis.h"
<> 144:ef7eb2e8f9f7 31 #include "pinmap.h"
<> 144:ef7eb2e8f9f7 32 #include "PeripheralPins.h"
<> 144:ef7eb2e8f9f7 33 #include "device_peripherals.h"
<> 144:ef7eb2e8f9f7 34 #include "sleepmodes.h"
<> 144:ef7eb2e8f9f7 35
<> 144:ef7eb2e8f9f7 36 #include "em_cmu.h"
<> 144:ef7eb2e8f9f7 37 #include "em_gpio.h"
<> 144:ef7eb2e8f9f7 38 #include "em_timer.h"
<> 144:ef7eb2e8f9f7 39
<> 144:ef7eb2e8f9f7 40 static uint32_t pwm_prescaler_div;
<> 144:ef7eb2e8f9f7 41
<> 144:ef7eb2e8f9f7 42 float pwmout_calculate_duty(uint32_t width_cycles, uint32_t period_cycles);
<> 144:ef7eb2e8f9f7 43 void pwmout_write_channel(uint32_t channel, float value);
<> 144:ef7eb2e8f9f7 44
<> 144:ef7eb2e8f9f7 45 uint32_t pwmout_get_channel_route(uint32_t channel)
<> 144:ef7eb2e8f9f7 46 {
<> 144:ef7eb2e8f9f7 47 MBED_ASSERT(channel != (PWMName) NC);
<> 144:ef7eb2e8f9f7 48
<> 144:ef7eb2e8f9f7 49 switch (channel) {
<> 144:ef7eb2e8f9f7 50 #ifdef TIMER_ROUTEPEN_CC0PEN
<> 144:ef7eb2e8f9f7 51 case PWM_CH0:
<> 144:ef7eb2e8f9f7 52 return TIMER_ROUTEPEN_CC0PEN;
<> 144:ef7eb2e8f9f7 53 break;
<> 144:ef7eb2e8f9f7 54 case PWM_CH1:
<> 144:ef7eb2e8f9f7 55 return TIMER_ROUTEPEN_CC1PEN;
<> 144:ef7eb2e8f9f7 56 break;
<> 144:ef7eb2e8f9f7 57 case PWM_CH2:
<> 144:ef7eb2e8f9f7 58 return TIMER_ROUTEPEN_CC2PEN;
<> 144:ef7eb2e8f9f7 59 break;
<> 144:ef7eb2e8f9f7 60 case PWM_CH3:
<> 144:ef7eb2e8f9f7 61 return TIMER_ROUTEPEN_CC3PEN;
<> 144:ef7eb2e8f9f7 62 break;
<> 144:ef7eb2e8f9f7 63 #else
<> 144:ef7eb2e8f9f7 64 case PWM_CH0:
<> 144:ef7eb2e8f9f7 65 return TIMER_ROUTE_CC0PEN;
<> 144:ef7eb2e8f9f7 66 break;
<> 144:ef7eb2e8f9f7 67 case PWM_CH1:
<> 144:ef7eb2e8f9f7 68 return TIMER_ROUTE_CC1PEN;
<> 144:ef7eb2e8f9f7 69 break;
<> 144:ef7eb2e8f9f7 70 case PWM_CH2:
<> 144:ef7eb2e8f9f7 71 return TIMER_ROUTE_CC2PEN;
<> 144:ef7eb2e8f9f7 72 break;
<> 144:ef7eb2e8f9f7 73 #endif
<> 144:ef7eb2e8f9f7 74 default:
<> 144:ef7eb2e8f9f7 75 return 0;
<> 144:ef7eb2e8f9f7 76 }
<> 144:ef7eb2e8f9f7 77 }
<> 144:ef7eb2e8f9f7 78
<> 144:ef7eb2e8f9f7 79 /*
<> 144:ef7eb2e8f9f7 80 * Disables the route location given. Returns true if it was enabled, false if it wasn't.
<> 144:ef7eb2e8f9f7 81 */
<> 144:ef7eb2e8f9f7 82 bool pwmout_disable_channel_route(uint32_t routeloc) {
<> 144:ef7eb2e8f9f7 83 #ifdef TIMER_ROUTEPEN_CC0PEN
<> 144:ef7eb2e8f9f7 84 if(PWM_TIMER->ROUTEPEN & routeloc) {
<> 144:ef7eb2e8f9f7 85 //This channel was in use, so disable
<> 144:ef7eb2e8f9f7 86 PWM_TIMER->ROUTEPEN &= ~routeloc;
<> 144:ef7eb2e8f9f7 87 return true;
<> 144:ef7eb2e8f9f7 88 }
<> 144:ef7eb2e8f9f7 89 #else
<> 144:ef7eb2e8f9f7 90 if(PWM_TIMER->ROUTE & routeloc) {
<> 144:ef7eb2e8f9f7 91 //This channel was in use, so disable
<> 144:ef7eb2e8f9f7 92 PWM_TIMER->ROUTE &= ~routeloc;
<> 144:ef7eb2e8f9f7 93 return true;
<> 144:ef7eb2e8f9f7 94 }
<> 144:ef7eb2e8f9f7 95 #endif
<> 144:ef7eb2e8f9f7 96 return false;
<> 144:ef7eb2e8f9f7 97 }
<> 144:ef7eb2e8f9f7 98
<> 144:ef7eb2e8f9f7 99 /*
<> 144:ef7eb2e8f9f7 100 * Check if a channel is active
<> 144:ef7eb2e8f9f7 101 */
<> 144:ef7eb2e8f9f7 102 bool pwmout_channel_route_active(uint32_t routeloc) {
<> 144:ef7eb2e8f9f7 103 #ifdef TIMER_ROUTEPEN_CC0PEN
<> 144:ef7eb2e8f9f7 104 if(PWM_TIMER->ROUTEPEN & routeloc) {
<> 144:ef7eb2e8f9f7 105 return true;
<> 144:ef7eb2e8f9f7 106 }
<> 144:ef7eb2e8f9f7 107 #else
<> 144:ef7eb2e8f9f7 108 if(PWM_TIMER->ROUTE & routeloc) {
<> 144:ef7eb2e8f9f7 109 return true;
<> 144:ef7eb2e8f9f7 110 }
<> 144:ef7eb2e8f9f7 111 #endif
<> 144:ef7eb2e8f9f7 112 return false;
<> 144:ef7eb2e8f9f7 113 }
<> 144:ef7eb2e8f9f7 114
<> 144:ef7eb2e8f9f7 115 /*
<> 144:ef7eb2e8f9f7 116 * Set the given route PEN flag
<> 144:ef7eb2e8f9f7 117 */
<> 144:ef7eb2e8f9f7 118 void pwmout_set_channel_route(uint32_t routeloc) {
<> 144:ef7eb2e8f9f7 119 #ifdef TIMER_ROUTEPEN_CC0PEN
<> 144:ef7eb2e8f9f7 120 PWM_TIMER->ROUTEPEN |= routeloc;
<> 144:ef7eb2e8f9f7 121 #else
<> 144:ef7eb2e8f9f7 122 PWM_TIMER->ROUTE |= routeloc;
<> 144:ef7eb2e8f9f7 123 #endif
<> 144:ef7eb2e8f9f7 124 }
<> 144:ef7eb2e8f9f7 125
<> 144:ef7eb2e8f9f7 126 /*
<> 144:ef7eb2e8f9f7 127 * Check if all routes are disabled
<> 144:ef7eb2e8f9f7 128 */
<> 144:ef7eb2e8f9f7 129 bool pwmout_all_inactive(void) {
<> 144:ef7eb2e8f9f7 130 #ifdef TIMER_ROUTEPEN_CC0PEN
<> 144:ef7eb2e8f9f7 131 if(PWM_TIMER->ROUTEPEN == _TIMER_ROUTEPEN_RESETVALUE) {
<> 144:ef7eb2e8f9f7 132 return true;
<> 144:ef7eb2e8f9f7 133 }
<> 144:ef7eb2e8f9f7 134 #else
<> 144:ef7eb2e8f9f7 135 if(PWM_TIMER->ROUTE & (TIMER_ROUTE_CC0PEN | TIMER_ROUTE_CC1PEN | TIMER_ROUTE_CC2PEN)) {
<> 144:ef7eb2e8f9f7 136 return true;
<> 144:ef7eb2e8f9f7 137 }
<> 144:ef7eb2e8f9f7 138 #endif
<> 144:ef7eb2e8f9f7 139 return false;
<> 144:ef7eb2e8f9f7 140 }
<> 144:ef7eb2e8f9f7 141
<> 144:ef7eb2e8f9f7 142 void pwmout_enable_pins(pwmout_t *obj, uint8_t enable)
<> 144:ef7eb2e8f9f7 143 {
<> 144:ef7eb2e8f9f7 144 if (enable) {
<> 144:ef7eb2e8f9f7 145 pin_mode(obj->pin, PushPull);
<> 144:ef7eb2e8f9f7 146 } else {
<> 144:ef7eb2e8f9f7 147 // TODO_LP return PinMode to the previous state
<> 144:ef7eb2e8f9f7 148 pin_mode(obj->pin, Disabled);
<> 144:ef7eb2e8f9f7 149 }
<> 144:ef7eb2e8f9f7 150 }
<> 144:ef7eb2e8f9f7 151
<> 144:ef7eb2e8f9f7 152 void pwmout_enable(pwmout_t *obj, uint8_t enable){
<> 144:ef7eb2e8f9f7 153 if (enable) {
<> 144:ef7eb2e8f9f7 154 // Set mode to PWM
<> 144:ef7eb2e8f9f7 155 PWM_TIMER->CC[obj->channel].CTRL = TIMER_CC_CTRL_MODE_PWM;
<> 144:ef7eb2e8f9f7 156 } else {
<> 144:ef7eb2e8f9f7 157 // Set mode to default (== disabled)
<> 144:ef7eb2e8f9f7 158 PWM_TIMER->CC[obj->channel].CTRL = _TIMER_CC_CTRL_MODE_DEFAULT;
<> 144:ef7eb2e8f9f7 159 }
<> 144:ef7eb2e8f9f7 160 }
<> 144:ef7eb2e8f9f7 161
<> 144:ef7eb2e8f9f7 162 void pwmout_init(pwmout_t *obj, PinName pin)
<> 144:ef7eb2e8f9f7 163 {
<> 144:ef7eb2e8f9f7 164 obj->channel = (PWMName) pinmap_peripheral(pin, PinMap_PWM);
<> 144:ef7eb2e8f9f7 165 obj->pin = pin;
<> 144:ef7eb2e8f9f7 166 MBED_ASSERT(obj->channel != (PWMName) NC);
<> 144:ef7eb2e8f9f7 167
<> 144:ef7eb2e8f9f7 168 /* Turn on clock */
<> 144:ef7eb2e8f9f7 169 CMU_ClockEnable(PWM_TIMER_CLOCK, true);
<> 144:ef7eb2e8f9f7 170
<> 144:ef7eb2e8f9f7 171 /* Turn on timer */
<> 144:ef7eb2e8f9f7 172 if(!(PWM_TIMER->STATUS & TIMER_STATUS_RUNNING)) {
<> 144:ef7eb2e8f9f7 173 TIMER_Init_TypeDef timerInit = TIMER_INIT_DEFAULT;
<> 144:ef7eb2e8f9f7 174 TIMER_Init(PWM_TIMER, &timerInit);
<> 144:ef7eb2e8f9f7 175 }
<> 144:ef7eb2e8f9f7 176
<> 144:ef7eb2e8f9f7 177 // Set route enable
<> 144:ef7eb2e8f9f7 178 if(pwmout_channel_route_active(pwmout_get_channel_route(obj->channel))) {
<> 144:ef7eb2e8f9f7 179 //This channel was already in use
<> 144:ef7eb2e8f9f7 180 //TODO: gracefully handle this case. mbed_error?
<> 144:ef7eb2e8f9f7 181 return;
<> 144:ef7eb2e8f9f7 182 } else {
<> 144:ef7eb2e8f9f7 183 pwmout_set_channel_route(pwmout_get_channel_route(obj->channel));
<> 144:ef7eb2e8f9f7 184 blockSleepMode(EM1);
<> 144:ef7eb2e8f9f7 185 pwmout_enable(obj, true);
<> 144:ef7eb2e8f9f7 186 pwmout_enable_pins(obj, true);
<> 144:ef7eb2e8f9f7 187 }
<> 144:ef7eb2e8f9f7 188
<> 144:ef7eb2e8f9f7 189 // Set route location
<> 144:ef7eb2e8f9f7 190 #ifdef _TIMER_ROUTELOC0_CC0LOC_LOC0
<> 144:ef7eb2e8f9f7 191 switch (obj->channel) {
<> 144:ef7eb2e8f9f7 192 case PWM_CH0:
<> 144:ef7eb2e8f9f7 193 PWM_TIMER->ROUTELOC0 &= ~_TIMER_ROUTELOC0_CC0LOC_MASK;
<> 144:ef7eb2e8f9f7 194 PWM_TIMER->ROUTELOC0 |= pinmap_find_function(pin,PinMap_PWM) << _TIMER_ROUTELOC0_CC0LOC_SHIFT;
<> 144:ef7eb2e8f9f7 195 break;
<> 144:ef7eb2e8f9f7 196 case PWM_CH1:
<> 144:ef7eb2e8f9f7 197 PWM_TIMER->ROUTELOC0 &= ~_TIMER_ROUTELOC0_CC1LOC_MASK;
<> 144:ef7eb2e8f9f7 198 PWM_TIMER->ROUTELOC0 |= pinmap_find_function(pin,PinMap_PWM)<< _TIMER_ROUTELOC0_CC1LOC_SHIFT;
<> 144:ef7eb2e8f9f7 199 break;
<> 144:ef7eb2e8f9f7 200 case PWM_CH2:
<> 144:ef7eb2e8f9f7 201 PWM_TIMER->ROUTELOC0 &= ~_TIMER_ROUTELOC0_CC2LOC_MASK;
<> 144:ef7eb2e8f9f7 202 PWM_TIMER->ROUTELOC0 |= pinmap_find_function(pin,PinMap_PWM) << _TIMER_ROUTELOC0_CC2LOC_SHIFT;
<> 144:ef7eb2e8f9f7 203 break;
<> 144:ef7eb2e8f9f7 204 case PWM_CH3:
<> 144:ef7eb2e8f9f7 205 PWM_TIMER->ROUTELOC0 &= ~_TIMER_ROUTELOC0_CC3LOC_MASK;
<> 144:ef7eb2e8f9f7 206 PWM_TIMER->ROUTELOC0 |= pinmap_find_function(pin,PinMap_PWM) << _TIMER_ROUTELOC0_CC3LOC_SHIFT;
<> 144:ef7eb2e8f9f7 207 break;
<> 144:ef7eb2e8f9f7 208 default:
<> 144:ef7eb2e8f9f7 209 MBED_ASSERT(false);
<> 144:ef7eb2e8f9f7 210 }
<> 144:ef7eb2e8f9f7 211 #else
<> 144:ef7eb2e8f9f7 212 // On P1, the route location is statically defined for the entire timer.
<> 144:ef7eb2e8f9f7 213 PWM_TIMER->ROUTE &= ~_TIMER_ROUTE_LOCATION_MASK;
<> 144:ef7eb2e8f9f7 214 if(pwmout_all_inactive()) {
<> 144:ef7eb2e8f9f7 215 PWM_TIMER->ROUTE |= pinmap_find_function(pin,PinMap_PWM) << _TIMER_ROUTE_LOCATION_SHIFT;
<> 144:ef7eb2e8f9f7 216 } else {
<> 144:ef7eb2e8f9f7 217 MBED_ASSERT((pinmap_find_function(pin,PinMap_PWM) << _TIMER_ROUTE_LOCATION_SHIFT) == (PWM_TIMER->ROUTE & _TIMER_ROUTE_LOCATION_MASK));
<> 144:ef7eb2e8f9f7 218 }
<> 144:ef7eb2e8f9f7 219 #endif
<> 144:ef7eb2e8f9f7 220
<> 144:ef7eb2e8f9f7 221 // Set default 20ms frequency and 0ms pulse width
<> 144:ef7eb2e8f9f7 222 pwmout_period(obj, 0.02);
<> 144:ef7eb2e8f9f7 223 }
<> 144:ef7eb2e8f9f7 224
<> 144:ef7eb2e8f9f7 225 void pwmout_free(pwmout_t *obj)
<> 144:ef7eb2e8f9f7 226 {
<> 144:ef7eb2e8f9f7 227 if(pwmout_disable_channel_route(pwmout_get_channel_route(obj->channel))) {
<> 144:ef7eb2e8f9f7 228 //Channel was previously enabled, so do housekeeping
<> 144:ef7eb2e8f9f7 229 unblockSleepMode(EM1);
<> 144:ef7eb2e8f9f7 230 } else {
<> 144:ef7eb2e8f9f7 231 //This channel was disabled already
<> 144:ef7eb2e8f9f7 232 }
<> 144:ef7eb2e8f9f7 233
<> 144:ef7eb2e8f9f7 234 pwmout_enable_pins(obj, false);
<> 144:ef7eb2e8f9f7 235
<> 144:ef7eb2e8f9f7 236 if(pwmout_all_inactive()) {
<> 144:ef7eb2e8f9f7 237 //Stop timer
<> 144:ef7eb2e8f9f7 238 PWM_TIMER->CMD = TIMER_CMD_STOP;
<> 144:ef7eb2e8f9f7 239 while(PWM_TIMER->STATUS & TIMER_STATUS_RUNNING);
<> 144:ef7eb2e8f9f7 240
<> 144:ef7eb2e8f9f7 241 //Disable clock
<> 144:ef7eb2e8f9f7 242 CMU_ClockEnable(PWM_TIMER_CLOCK, false);
<> 144:ef7eb2e8f9f7 243 }
<> 144:ef7eb2e8f9f7 244 }
<> 144:ef7eb2e8f9f7 245
<> 144:ef7eb2e8f9f7 246 void pwmout_write(pwmout_t *obj, float value)
<> 144:ef7eb2e8f9f7 247 {
<> 144:ef7eb2e8f9f7 248 pwmout_write_channel(obj->channel, value);
<> 144:ef7eb2e8f9f7 249 }
<> 144:ef7eb2e8f9f7 250
<> 144:ef7eb2e8f9f7 251 void pwmout_write_channel(uint32_t channel, float value) {
<> 144:ef7eb2e8f9f7 252 uint32_t width_cycles = 0;
<> 144:ef7eb2e8f9f7 253 if (value < 0.0f) {
<> 144:ef7eb2e8f9f7 254 width_cycles = 0;
<> 144:ef7eb2e8f9f7 255 } else if (value >= 1.0f) {
<> 144:ef7eb2e8f9f7 256 width_cycles = PWM_TIMER->TOPB + 1;
<> 144:ef7eb2e8f9f7 257 } else {
<> 144:ef7eb2e8f9f7 258 width_cycles = (uint16_t)((float)PWM_TIMER->TOPB * value);
<> 144:ef7eb2e8f9f7 259 }
<> 144:ef7eb2e8f9f7 260
<> 144:ef7eb2e8f9f7 261 TIMER_CompareBufSet(PWM_TIMER, channel, width_cycles);
<> 144:ef7eb2e8f9f7 262 }
<> 144:ef7eb2e8f9f7 263
<> 144:ef7eb2e8f9f7 264 float pwmout_read(pwmout_t *obj)
<> 144:ef7eb2e8f9f7 265 {
<> 144:ef7eb2e8f9f7 266 return pwmout_calculate_duty(TIMER_CaptureGet(PWM_TIMER, obj->channel), TIMER_TopGet(PWM_TIMER));
<> 144:ef7eb2e8f9f7 267 }
<> 144:ef7eb2e8f9f7 268
<> 144:ef7eb2e8f9f7 269 float pwmout_calculate_duty(uint32_t width_cycles, uint32_t period_cycles) {
<> 144:ef7eb2e8f9f7 270 if(width_cycles > period_cycles) {
<> 144:ef7eb2e8f9f7 271 return 1.0f;
<> 144:ef7eb2e8f9f7 272 }
<> 144:ef7eb2e8f9f7 273 else if (width_cycles == 0) {
<> 144:ef7eb2e8f9f7 274 return 0.0f;
<> 144:ef7eb2e8f9f7 275 }
<> 144:ef7eb2e8f9f7 276 else {
<> 144:ef7eb2e8f9f7 277 return (float) width_cycles / (float) period_cycles;
<> 144:ef7eb2e8f9f7 278 }
<> 144:ef7eb2e8f9f7 279 }
<> 144:ef7eb2e8f9f7 280
<> 144:ef7eb2e8f9f7 281 // Set the PWM period, keeping the duty cycle the same.
<> 144:ef7eb2e8f9f7 282 void pwmout_period(pwmout_t *obj, float seconds)
<> 144:ef7eb2e8f9f7 283 {
<> 144:ef7eb2e8f9f7 284 // Find the lowest prescaler divider possible.
<> 144:ef7eb2e8f9f7 285 // This gives us max resolution for a given period
<> 144:ef7eb2e8f9f7 286
<> 144:ef7eb2e8f9f7 287 //The value of the top register if prescaler is set to 0
<> 144:ef7eb2e8f9f7 288 uint32_t cycles = (uint32_t)REFERENCE_FREQUENCY * seconds;
<> 144:ef7eb2e8f9f7 289 pwm_prescaler_div = 0;
<> 144:ef7eb2e8f9f7 290
<> 144:ef7eb2e8f9f7 291 //The top register is only 16 bits, so we keep dividing till we are below 0xFFFF
<> 144:ef7eb2e8f9f7 292 while (cycles > 0xFFFF) {
<> 144:ef7eb2e8f9f7 293 cycles /= 2;
<> 144:ef7eb2e8f9f7 294 pwm_prescaler_div++;
<> 144:ef7eb2e8f9f7 295
<> 144:ef7eb2e8f9f7 296 //Max pwm_prescaler_div supported is 10
<> 144:ef7eb2e8f9f7 297 if (pwm_prescaler_div > 10) {
<> 144:ef7eb2e8f9f7 298 pwm_prescaler_div = 10;
<> 144:ef7eb2e8f9f7 299 cycles = 0xFFFF; //Set it to max possible value;
<> 144:ef7eb2e8f9f7 300 break;
<> 144:ef7eb2e8f9f7 301 }
<> 144:ef7eb2e8f9f7 302 }
<> 144:ef7eb2e8f9f7 303
<> 144:ef7eb2e8f9f7 304 //Check if anything changed
<> 144:ef7eb2e8f9f7 305 if(((PWM_TIMER->CTRL & ~_TIMER_CTRL_PRESC_MASK) == (pwm_prescaler_div << _TIMER_CTRL_PRESC_SHIFT)) && (TIMER_TopGet(PWM_TIMER) == cycles)) return;
<> 144:ef7eb2e8f9f7 306
<> 144:ef7eb2e8f9f7 307 //Save previous period for recalculation of duty cycles
<> 144:ef7eb2e8f9f7 308 uint32_t previous_period_cycles = PWM_TIMER->TOPB;
<> 144:ef7eb2e8f9f7 309
<> 144:ef7eb2e8f9f7 310 //Set prescaler
<> 144:ef7eb2e8f9f7 311 PWM_TIMER->CTRL = (PWM_TIMER->CTRL & ~_TIMER_CTRL_PRESC_MASK) | (pwm_prescaler_div << _TIMER_CTRL_PRESC_SHIFT);
<> 144:ef7eb2e8f9f7 312
<> 144:ef7eb2e8f9f7 313 //Set Top Value, which controls the PWM period
<> 144:ef7eb2e8f9f7 314 TIMER_TopBufSet(PWM_TIMER, cycles);
<> 144:ef7eb2e8f9f7 315
<> 144:ef7eb2e8f9f7 316 //For each active channel, re-calculate the compare value
<> 144:ef7eb2e8f9f7 317 uint32_t channel = 0;
<> 144:ef7eb2e8f9f7 318 while(pwmout_get_channel_route(channel) != 0) {
<> 144:ef7eb2e8f9f7 319 if(pwmout_channel_route_active(channel)) {
<> 144:ef7eb2e8f9f7 320 //recalc and reset compare value
<> 144:ef7eb2e8f9f7 321 pwmout_write_channel(channel, pwmout_calculate_duty(PWM_TIMER->CC[channel].CCVB, previous_period_cycles));
<> 144:ef7eb2e8f9f7 322 }
<> 144:ef7eb2e8f9f7 323 channel++;
<> 144:ef7eb2e8f9f7 324 }
<> 144:ef7eb2e8f9f7 325 }
<> 144:ef7eb2e8f9f7 326
<> 144:ef7eb2e8f9f7 327 void pwmout_period_ms(pwmout_t *obj, int ms)
<> 144:ef7eb2e8f9f7 328 {
<> 144:ef7eb2e8f9f7 329 pwmout_period(obj, ms / 1000.0f);
<> 144:ef7eb2e8f9f7 330 }
<> 144:ef7eb2e8f9f7 331
<> 144:ef7eb2e8f9f7 332 void pwmout_period_us(pwmout_t *obj, int us)
<> 144:ef7eb2e8f9f7 333 {
<> 144:ef7eb2e8f9f7 334 pwmout_period(obj, us / 1000000.0f);
<> 144:ef7eb2e8f9f7 335 }
<> 144:ef7eb2e8f9f7 336
<> 144:ef7eb2e8f9f7 337 void pwmout_pulsewidth(pwmout_t *obj, float seconds)
<> 144:ef7eb2e8f9f7 338 {
<> 144:ef7eb2e8f9f7 339 uint16_t width_cycles = (uint16_t) (((float) (REFERENCE_FREQUENCY >> pwm_prescaler_div)) * seconds);
<> 144:ef7eb2e8f9f7 340 TIMER_CompareBufSet(PWM_TIMER, obj->channel, width_cycles);
<> 144:ef7eb2e8f9f7 341 }
<> 144:ef7eb2e8f9f7 342
<> 144:ef7eb2e8f9f7 343 void pwmout_pulsewidth_ms(pwmout_t *obj, int ms)
<> 144:ef7eb2e8f9f7 344 {
<> 144:ef7eb2e8f9f7 345 uint16_t width_cycles = (uint16_t) ((REFERENCE_FREQUENCY >> pwm_prescaler_div) * ms) / 1000;
<> 144:ef7eb2e8f9f7 346 TIMER_CompareBufSet(PWM_TIMER, obj->channel, width_cycles);
<> 144:ef7eb2e8f9f7 347 }
<> 144:ef7eb2e8f9f7 348
<> 144:ef7eb2e8f9f7 349 void pwmout_pulsewidth_us(pwmout_t *obj, int us)
<> 144:ef7eb2e8f9f7 350 {
<> 144:ef7eb2e8f9f7 351 uint16_t width_cycles = (uint16_t) ((REFERENCE_FREQUENCY >> pwm_prescaler_div) * us) / 1000000;
<> 144:ef7eb2e8f9f7 352 TIMER_CompareBufSet(PWM_TIMER, obj->channel, width_cycles);
<> 144:ef7eb2e8f9f7 353 }
<> 144:ef7eb2e8f9f7 354
<> 144:ef7eb2e8f9f7 355 #endif