Martin Cottrell
No Changes
Dependencies: BLE_API mbed-dev-bin nRF51822
Fork of
microbit-dal
by 
Lancaster University
source/drivers/DynamicPwm.cpp@75:ae9a17da71af, 2017-01-13 (annotated)
- Committer:
- Asimov
- Date:
- Fri Jan 13 21:14:06 2017 +0000
- Revision:
- 75:ae9a17da71af
- Parent:
- 3:d86a4ddc1867
No Changes
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| Jonathan Austin |
1:8aa5cdb4ab67 | 1 | /* |
| Jonathan Austin |
1:8aa5cdb4ab67 | 2 | The MIT License (MIT) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 3 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 4 | Copyright (c) 2016 British Broadcasting Corporation. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 5 | This software is provided by Lancaster University by arrangement with the BBC. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 6 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 7 | Permission is hereby granted, free of charge, to any person obtaining a |
| Jonathan Austin |
1:8aa5cdb4ab67 | 8 | copy of this software and associated documentation files (the "Software"), |
| Jonathan Austin |
1:8aa5cdb4ab67 | 9 | to deal in the Software without restriction, including without limitation |
| Jonathan Austin |
1:8aa5cdb4ab67 | 10 | the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| Jonathan Austin |
1:8aa5cdb4ab67 | 11 | and/or sell copies of the Software, and to permit persons to whom the |
| Jonathan Austin |
1:8aa5cdb4ab67 | 12 | Software is furnished to do so, subject to the following conditions: |
| Jonathan Austin |
1:8aa5cdb4ab67 | 13 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 14 | The above copyright notice and this permission notice shall be included in |
| Jonathan Austin |
1:8aa5cdb4ab67 | 15 | all copies or substantial portions of the Software. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 16 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 17 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| Jonathan Austin |
1:8aa5cdb4ab67 | 18 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| Jonathan Austin |
1:8aa5cdb4ab67 | 19 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| Jonathan Austin |
1:8aa5cdb4ab67 | 20 | THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| Jonathan Austin |
1:8aa5cdb4ab67 | 21 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| Jonathan Austin |
1:8aa5cdb4ab67 | 22 | FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
| Jonathan Austin |
1:8aa5cdb4ab67 | 23 | DEALINGS IN THE SOFTWARE. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 24 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 25 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 26 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 27 | * Class definition for DynamicPwm. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 28 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 29 | * This class addresses a few issues found in the underlying libraries. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 30 | * This provides the ability for a neat, clean swap between PWM channels. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 31 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 32 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 33 | #include "MicroBitConfig.h" |
| Jonathan Austin |
1:8aa5cdb4ab67 | 34 | #include "DynamicPwm.h" |
| Jonathan Austin |
1:8aa5cdb4ab67 | 35 | #include "MicroBitPin.h" |
| Jonathan Austin |
1:8aa5cdb4ab67 | 36 | #include "ErrorNo.h" |
| Jonathan Austin |
1:8aa5cdb4ab67 | 37 | |
| LancasterUniversity | 3:d86a4ddc1867 | 38 | DynamicPwm* DynamicPwm::pwms[NO_PWMS] = { NULL, NULL, NULL }; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 39 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 40 | uint8_t DynamicPwm::lastUsed = NO_PWMS+1; //set it to out of range i.e. 4 so we know it hasn't been used yet. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 41 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 42 | uint16_t DynamicPwm::sharedPeriod = 0; //set the shared period to an unknown state |
| Jonathan Austin |
1:8aa5cdb4ab67 | 43 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 44 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 45 | * Reassigns an already operational PWM channel to the given pin. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 46 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 47 | * @param pin The desired pin to begin a PWM wave. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 48 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 49 | * @param oldPin The pin to stop running a PWM wave. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 50 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 51 | * @param channel_number The GPIOTE channel being used to drive this PWM channel |
| Jonathan Austin |
1:8aa5cdb4ab67 | 52 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 53 | * TODO: Merge into mbed, at a later date. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 54 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 55 | void gpiote_reinit(PinName pin, PinName oldPin, uint8_t channel_number) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 56 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 57 | // Connect GPIO input buffers and configure PWM_OUTPUT_PIN_NUMBER as an output. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 58 | NRF_GPIO->PIN_CNF[pin] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 59 | | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 60 | | (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 61 | | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 62 | | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 63 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 64 | NRF_GPIO->OUTCLR = (1 << oldPin); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 65 | NRF_GPIO->OUTCLR = (1 << pin); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 66 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 67 | /* Finally configure the channel as the caller expects. If OUTINIT works, the channel is configured properly. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 68 | If it does not, the channel output inheritance sets the proper level. */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 69 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 70 | NRF_GPIOTE->CONFIG[channel_number] = (GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos) | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 71 | ((uint32_t)pin << GPIOTE_CONFIG_PSEL_Pos) | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 72 | ((uint32_t)GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos) | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 73 | ((uint32_t)GPIOTE_CONFIG_OUTINIT_Low << GPIOTE_CONFIG_OUTINIT_Pos); // ((uint32_t)GPIOTE_CONFIG_OUTINIT_High << |
| Jonathan Austin |
1:8aa5cdb4ab67 | 74 | // GPIOTE_CONFIG_OUTINIT_Pos);// |
| Jonathan Austin |
1:8aa5cdb4ab67 | 75 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 76 | /* Three NOPs are required to make sure configuration is written before setting tasks or getting events */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 77 | __NOP(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 78 | __NOP(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 79 | __NOP(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 80 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 81 | NRF_TIMER2->CC[channel_number] = 0; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 82 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 83 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 84 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 85 | * An internal constructor used when allocating a new DynamicPwm instance. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 86 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 87 | * @param pin the name of the pin for the pwm to target |
| Jonathan Austin |
1:8aa5cdb4ab67 | 88 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 89 | * @param persistance the level of persistence for this pin PWM_PERSISTENCE_PERSISTENT (can not be replaced until freed, should only be used for system services really.) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 90 | * or PWM_PERSISTENCE_TRANSIENT (can be replaced at any point if a channel is required.) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 91 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 92 | DynamicPwm::DynamicPwm(PinName pin, PwmPersistence persistence) : PwmOut(pin) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 93 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 94 | this->flags = persistence; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 95 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 96 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 97 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 98 | * Redirects the pwm channel to point at a different pin. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 99 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 100 | * @param pin the desired pin to output a PWM wave. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 101 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 102 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 103 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 104 | * pwm->redirect(p0); // pwm is now produced on p0 |
| Jonathan Austin |
1:8aa5cdb4ab67 | 105 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 106 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 107 | void DynamicPwm::redirect(PinName pin) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 108 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 109 | gpiote_reinit(pin, _pwm.pin, (uint8_t)_pwm.pwm); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 110 | this->_pwm.pin = pin; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 111 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 112 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 113 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 114 | * Creates a new DynamicPwm instance, or reuses an existing instance that |
| Jonathan Austin |
1:8aa5cdb4ab67 | 115 | * has a persistence level of PWM_PERSISTENCE_TRANSIENT. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 116 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 117 | * @param pin the name of the pin for the pwm to target |
| Jonathan Austin |
1:8aa5cdb4ab67 | 118 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 119 | * @param persistance the level of persistence for this pin PWM_PERSISTENCE_PERSISTENT (can not be replaced until freed, should only be used for system services really.) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 120 | * or PWM_PERSISTENCE_TRANSIENT (can be replaced at any point if a channel is required.) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 121 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 122 | * @return a pointer to the first available free pwm channel - or the first one that can be reallocated. If |
| Jonathan Austin |
1:8aa5cdb4ab67 | 123 | * no channels are available, NULL is returned. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 124 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 125 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 126 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 127 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 128 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 129 | DynamicPwm* DynamicPwm::allocate(PinName pin, PwmPersistence persistence) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 130 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 131 | //try to find a blank spot first |
| Jonathan Austin |
1:8aa5cdb4ab67 | 132 | for(int i = 0; i < NO_PWMS; i++) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 133 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 134 | if(pwms[i] == NULL) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 135 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 136 | lastUsed = i; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 137 | pwms[i] = new DynamicPwm(pin, persistence); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 138 | return pwms[i]; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 139 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 140 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 141 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 142 | //no blank spot.. try to find a transient PWM |
| Jonathan Austin |
1:8aa5cdb4ab67 | 143 | int channelIterator = (lastUsed + 1 > NO_PWMS - 1) ? 0 : lastUsed + 1; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 144 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 145 | while(channelIterator != lastUsed) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 146 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 147 | if(pwms[channelIterator]->flags & PWM_PERSISTENCE_TRANSIENT) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 148 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 149 | lastUsed = channelIterator; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 150 | pwms[channelIterator]->flags = persistence; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 151 | pwms[channelIterator]->redirect(pin); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 152 | return pwms[channelIterator]; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 153 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 154 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 155 | channelIterator = (channelIterator + 1 > NO_PWMS - 1) ? 0 : channelIterator + 1; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 156 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 157 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 158 | //if we haven't found a free one, we must try to allocate the last used... |
| Jonathan Austin |
1:8aa5cdb4ab67 | 159 | if(pwms[lastUsed]->flags & PWM_PERSISTENCE_TRANSIENT) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 160 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 161 | pwms[lastUsed]->flags = persistence; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 162 | pwms[lastUsed]->redirect(pin); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 163 | return pwms[lastUsed]; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 164 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 165 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 166 | //well if we have no transient channels - we can't give any away! :( return null |
| Jonathan Austin |
1:8aa5cdb4ab67 | 167 | return (DynamicPwm*)NULL; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 168 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 169 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 170 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 171 | * Frees this DynamicPwm instance for reuse. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 172 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 173 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 174 | * DynamicPwm* pwm = DynamicPwm::allocate(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 175 | * pwm->release(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 176 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 177 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 178 | void DynamicPwm::release() |
| Jonathan Austin |
1:8aa5cdb4ab67 | 179 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 180 | //free the pwm instance. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 181 | NRF_GPIOTE->CONFIG[(uint8_t) _pwm.pwm] = 0; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 182 | pwmout_free(&_pwm); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 183 | this->flags = PWM_PERSISTENCE_TRANSIENT; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 184 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 185 | //set the pointer to this object to null... |
| Jonathan Austin |
1:8aa5cdb4ab67 | 186 | for(int i =0; i < NO_PWMS; i++) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 187 | if(pwms[i] == this) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 188 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 189 | delete pwms[i]; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 190 | pwms[i] = NULL; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 191 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 192 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 193 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 194 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 195 | * A lightweight wrapper around the super class' write in order to capture the value |
| Jonathan Austin |
1:8aa5cdb4ab67 | 196 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 197 | * @param value the duty cycle percentage in floating point format. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 198 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 199 | * @return MICROBIT_OK on success, MICROBIT_INVALID_PARAMETER if value is out of range |
| Jonathan Austin |
1:8aa5cdb4ab67 | 200 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 201 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 202 | * DynamicPwm* pwm = DynamicPwm::allocate(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 203 | * pwm->write(0.5); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 204 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 205 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 206 | int DynamicPwm::write(float value){ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 207 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 208 | if(value < 0) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 209 | return MICROBIT_INVALID_PARAMETER; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 210 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 211 | PwmOut::write(value); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 212 | lastValue = value; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 213 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 214 | return MICROBIT_OK; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 215 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 216 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 217 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 218 | * Retreives the PinName associated with this DynamicPwm instance. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 219 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 220 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 221 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 222 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 223 | * // returns the PinName n. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 224 | * pwm->getPinName(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 225 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 226 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 227 | * @note This should be used to check that the DynamicPwm instance has not |
| Jonathan Austin |
1:8aa5cdb4ab67 | 228 | * been reallocated for use in another part of a program. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 229 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 230 | PinName DynamicPwm::getPinName() |
| Jonathan Austin |
1:8aa5cdb4ab67 | 231 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 232 | return _pwm.pin; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 233 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 234 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 235 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 236 | * Retreives the last value that has been written to this DynamicPwm instance. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 237 | * in the range 0 - 1023 inclusive. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 238 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 239 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 240 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 241 | * pwm->write(0.5); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 242 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 243 | * // will return 512. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 244 | * pwm->getValue(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 245 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 246 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 247 | int DynamicPwm::getValue() |
| Jonathan Austin |
1:8aa5cdb4ab67 | 248 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 249 | return (float)lastValue * float(MICROBIT_PIN_MAX_OUTPUT); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 250 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 251 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 252 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 253 | * Retreives the current period in use by the entire PWM module in microseconds. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 254 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 255 | * Example: |
| Jonathan Austin |
1:8aa5cdb4ab67 | 256 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 257 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 258 | * pwm->getPeriod(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 259 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 260 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 261 | int DynamicPwm::getPeriodUs() |
| Jonathan Austin |
1:8aa5cdb4ab67 | 262 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 263 | return sharedPeriod; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 264 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 265 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 266 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 267 | * Retreives the current period in use by the entire PWM module in milliseconds. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 268 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 269 | * Example: |
| Jonathan Austin |
1:8aa5cdb4ab67 | 270 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 271 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 272 | * pwm->setPeriodUs(20000); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 273 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 274 | * // will return 20000 |
| Jonathan Austin |
1:8aa5cdb4ab67 | 275 | * pwm->getPeriod(); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 276 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 277 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 278 | int DynamicPwm::getPeriod() |
| Jonathan Austin |
1:8aa5cdb4ab67 | 279 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 280 | return getPeriodUs() / 1000; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 281 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 282 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 283 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 284 | * Sets the period used by the WHOLE PWM module. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 285 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 286 | * @param period the desired period in microseconds. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 287 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 288 | * @return MICROBIT_OK on success, MICROBIT_INVALID_PARAMETER if period is out of range |
| Jonathan Austin |
1:8aa5cdb4ab67 | 289 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 290 | * Example: |
| Jonathan Austin |
1:8aa5cdb4ab67 | 291 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 292 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 293 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 294 | * // period now is 20ms |
| Jonathan Austin |
1:8aa5cdb4ab67 | 295 | * pwm->setPeriodUs(20000); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 296 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 297 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 298 | * @note Any changes to the period will AFFECT ALL CHANNELS. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 299 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 300 | int DynamicPwm::setPeriodUs(int period) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 301 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 302 | if(period < 0) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 303 | return MICROBIT_INVALID_PARAMETER; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 304 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 305 | //#HACK this forces mbed to update the pulse width calculation. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 306 | period_us(period); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 307 | write(lastValue); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 308 | sharedPeriod = period; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 309 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 310 | return MICROBIT_OK; |
| Jonathan Austin |
1:8aa5cdb4ab67 | 311 | } |
| Jonathan Austin |
1:8aa5cdb4ab67 | 312 | |
| Jonathan Austin |
1:8aa5cdb4ab67 | 313 | /** |
| Jonathan Austin |
1:8aa5cdb4ab67 | 314 | * Sets the period used by the WHOLE PWM module. Any changes to the period will AFFECT ALL CHANNELS. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 315 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 316 | * @param period the desired period in milliseconds. |
| Jonathan Austin |
1:8aa5cdb4ab67 | 317 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 318 | * @return MICROBIT_OK on success, MICROBIT_INVALID_PARAMETER if period is out of range |
| Jonathan Austin |
1:8aa5cdb4ab67 | 319 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 320 | * Example: |
| Jonathan Austin |
1:8aa5cdb4ab67 | 321 | * @code |
| Jonathan Austin |
1:8aa5cdb4ab67 | 322 | * DynamicPwm* pwm = DynamicPwm::allocate(PinName n); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 323 | * |
| Jonathan Austin |
1:8aa5cdb4ab67 | 324 | * // period now is 20ms |
| Jonathan Austin |
1:8aa5cdb4ab67 | 325 | * pwm->setPeriod(20); |
| Jonathan Austin |
1:8aa5cdb4ab67 | 326 | * @endcode |
| Jonathan Austin |
1:8aa5cdb4ab67 | 327 | */ |
| Jonathan Austin |
1:8aa5cdb4ab67 | 328 | int DynamicPwm::setPeriod(int period) |
| Jonathan Austin |
1:8aa5cdb4ab67 | 329 | { |
| Jonathan Austin |
1:8aa5cdb4ab67 | 330 | return setPeriodUs(period * 1000); |
| LancasterUniversity | 3:d86a4ddc1867 | 331 | } |