Yihui Xiong
initial
Diff: mbed-src/targets/hal/TARGET_NORDIC/TARGET_MCU_NRF51822/pwmout_api.c
- Revision:
- 1:9d3b497333c0
- Parent:
- 0:638edba3adf6
--- a/mbed-src/targets/hal/TARGET_NORDIC/TARGET_MCU_NRF51822/pwmout_api.c Mon Jan 11 02:32:24 2016 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,347 +0,0 @@
-/* mbed Microcontroller Library
- * Copyright (c) 2013 Nordic Semiconductor
- *
- * 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.
- */
-#include "mbed_assert.h"
-#include "pwmout_api.h"
-#include "cmsis.h"
-#include "pinmap.h"
-#include "mbed_error.h"
-
-#define NO_PWMS 3
-#define TIMER_PRECISION 4 //4us ticks
-#define TIMER_PRESCALER 6 //4us ticks = 16Mhz/(2**6)
-static const PinMap PinMap_PWM[] = {
- {p0, PWM_1, 1},
- {p1, PWM_1, 1},
- {p2, PWM_1, 1},
- {p3, PWM_1, 1},
- {p4, PWM_1, 1},
- {p5, PWM_1, 1},
- {p6, PWM_1, 1},
- {p7, PWM_1, 1},
- {p8, PWM_1, 1},
- {p9, PWM_1, 1},
- {p10, PWM_1, 1},
- {p11, PWM_1, 1},
- {p12, PWM_1, 1},
- {p13, PWM_1, 1},
- {p14, PWM_1, 1},
- {p15, PWM_1, 1},
- {p16, PWM_1, 1},
- {p17, PWM_1, 1},
- {p18, PWM_1, 1},
- {p19, PWM_1, 1},
- {p20, PWM_1, 1},
- {p21, PWM_1, 1},
- {p22, PWM_1, 1},
- {p23, PWM_1, 1},
- {p24, PWM_1, 1},
- {p25, PWM_1, 1},
- {p28, PWM_1, 1},
- {p29, PWM_1, 1},
- {p30, PWM_1, 1},
- {NC, NC, 0}
-};
-
-static NRF_TIMER_Type *Timers[1] = {
- NRF_TIMER2
-};
-
-uint16_t PERIOD = 20000 / TIMER_PRECISION; //20ms
-uint8_t PWM_taken[NO_PWMS] = {0, 0, 0};
-uint16_t PULSE_WIDTH[NO_PWMS] = {1, 1, 1}; //set to 1 instead of 0
-uint16_t ACTUAL_PULSE[NO_PWMS] = {0, 0, 0};
-
-
-/** @brief Function for handling timer 2 peripheral interrupts.
- */
-#ifdef __cplusplus
-extern "C" {
-#endif
-void TIMER2_IRQHandler(void)
-{
- NRF_TIMER2->EVENTS_COMPARE[3] = 0;
- NRF_TIMER2->CC[3] = PERIOD;
-
- if (PWM_taken[0]) {
- NRF_TIMER2->CC[0] = PULSE_WIDTH[0];
- }
- if (PWM_taken[1]) {
- NRF_TIMER2->CC[1] = PULSE_WIDTH[1];
- }
- if (PWM_taken[2]) {
- NRF_TIMER2->CC[2] = PULSE_WIDTH[2];
- }
-
- NRF_TIMER2->TASKS_START = 1;
-}
-
-#ifdef __cplusplus
-}
-#endif
-/** @brief Function for initializing the Timer peripherals.
- */
-void timer_init(uint8_t pwmChoice)
-{
- NRF_TIMER_Type *timer = Timers[0];
- timer->TASKS_STOP = 0;
-
- if (pwmChoice == 0) {
- timer->POWER = 0;
- timer->POWER = 1;
- timer->MODE = TIMER_MODE_MODE_Timer;
- timer->BITMODE = TIMER_BITMODE_BITMODE_16Bit << TIMER_BITMODE_BITMODE_Pos;
- timer->PRESCALER = TIMER_PRESCALER;
- timer->CC[3] = PERIOD;
- }
-
- timer->CC[pwmChoice] = PULSE_WIDTH[pwmChoice];
-
- //high priority application interrupt
- NVIC_SetPriority(TIMER2_IRQn, 1);
- NVIC_EnableIRQ(TIMER2_IRQn);
-
- timer->TASKS_START = 0x01;
-}
-
-/** @brief Function for initializing the GPIO Tasks/Events peripheral.
- */
-void gpiote_init(PinName pin, uint8_t channel_number)
-{
- // Connect GPIO input buffers and configure PWM_OUTPUT_PIN_NUMBER as an output.
- NRF_GPIO->PIN_CNF[pin] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
- | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
- | (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos)
- | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)
- | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
- NRF_GPIO->OUTCLR = (1UL << pin);
- // Configure GPIOTE channel 0 to toggle the PWM pin state
- // @note Only one GPIOTE task can be connected to an output pin.
- /* Configure channel to Pin31, not connected to the pin, and configure as a tasks that will set it to proper level */
- NRF_GPIOTE->CONFIG[channel_number] = (GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos) |
- (31UL << GPIOTE_CONFIG_PSEL_Pos) |
- (GPIOTE_CONFIG_POLARITY_HiToLo << GPIOTE_CONFIG_POLARITY_Pos);
- /* Three NOPs are required to make sure configuration is written before setting tasks or getting events */
- __NOP();
- __NOP();
- __NOP();
- /* Launch the task to take the GPIOTE channel output to the desired level */
- NRF_GPIOTE->TASKS_OUT[channel_number] = 1;
-
- /* Finally configure the channel as the caller expects. If OUTINIT works, the channel is configured properly.
- If it does not, the channel output inheritance sets the proper level. */
- NRF_GPIOTE->CONFIG[channel_number] = (GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos) |
- ((uint32_t)pin << GPIOTE_CONFIG_PSEL_Pos) |
- ((uint32_t)GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos) |
- ((uint32_t)GPIOTE_CONFIG_OUTINIT_Low << GPIOTE_CONFIG_OUTINIT_Pos); // ((uint32_t)GPIOTE_CONFIG_OUTINIT_High <<
- // GPIOTE_CONFIG_OUTINIT_Pos);//
-
- /* Three NOPs are required to make sure configuration is written before setting tasks or getting events */
- __NOP();
- __NOP();
- __NOP();
-}
-
-/** @brief Function for initializing the Programmable Peripheral Interconnect peripheral.
- */
-static void ppi_init(uint8_t pwm)
-{
- //using ppi channels 0-7 (only 0-7 are available)
- uint8_t channel_number = 2 * pwm;
- NRF_TIMER_Type *timer = Timers[0];
-
- // Configure PPI channel 0 to toggle ADVERTISING_LED_PIN_NO on every TIMER1 COMPARE[0] match
- NRF_PPI->CH[channel_number].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[pwm];
- NRF_PPI->CH[channel_number + 1].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[pwm];
- NRF_PPI->CH[channel_number].EEP = (uint32_t)&timer->EVENTS_COMPARE[pwm];
- NRF_PPI->CH[channel_number + 1].EEP = (uint32_t)&timer->EVENTS_COMPARE[3];
-
- // Enable PPI channels.
- NRF_PPI->CHEN |= (1 << channel_number) |
- (1 << (channel_number + 1));
-}
-
-void setModulation(pwmout_t *obj, uint8_t toggle, uint8_t high)
-{
- if (high) {
- NRF_GPIOTE->CONFIG[obj->pwm] |= ((uint32_t)GPIOTE_CONFIG_OUTINIT_High << GPIOTE_CONFIG_OUTINIT_Pos);
- if (toggle) {
- NRF_GPIOTE->CONFIG[obj->pwm] |= (GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos) |
- ((uint32_t)GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos);
- } else {
- NRF_GPIOTE->CONFIG[obj->pwm] &= ~((uint32_t)GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos);
- NRF_GPIOTE->CONFIG[obj->pwm] |= ((uint32_t)GPIOTE_CONFIG_POLARITY_LoToHi << GPIOTE_CONFIG_POLARITY_Pos);
- }
- } else {
- NRF_GPIOTE->CONFIG[obj->pwm] &= ~((uint32_t)GPIOTE_CONFIG_OUTINIT_High << GPIOTE_CONFIG_OUTINIT_Pos);
-
- if (toggle) {
- NRF_GPIOTE->CONFIG[obj->pwm] |= (GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos) |
- ((uint32_t)GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos);
- } else {
- NRF_GPIOTE->CONFIG[obj->pwm] &= ~((uint32_t)GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos);
- NRF_GPIOTE->CONFIG[obj->pwm] |= ((uint32_t)GPIOTE_CONFIG_POLARITY_HiToLo << GPIOTE_CONFIG_POLARITY_Pos);
- }
- }
-}
-
-void pwmout_init(pwmout_t *obj, PinName pin)
-{
- // determine the channel
- uint8_t pwmOutSuccess = 0;
- PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
-
- MBED_ASSERT(pwm != (PWMName)NC);
-
- if (PWM_taken[(uint8_t)pwm]) {
- for (uint8_t i = 1; !pwmOutSuccess && (i<NO_PWMS); i++) {
- if (!PWM_taken[i]) {
- pwm = (PWMName)i;
- PWM_taken[i] = 1;
- pwmOutSuccess = 1;
- }
- }
- } else {
- pwmOutSuccess = 1;
- PWM_taken[(uint8_t)pwm] = 1;
- }
-
- if (!pwmOutSuccess) {
- error("PwmOut pin mapping failed. All available PWM channels are in use.");
- }
-
- obj->pwm = pwm;
- obj->pin = pin;
-
- gpiote_init(pin, (uint8_t)pwm);
- ppi_init((uint8_t)pwm);
-
- if (pwm == 0) {
- NRF_POWER->TASKS_CONSTLAT = 1;
- }
-
- timer_init((uint8_t)pwm);
-
- //default to 20ms: standard for servos, and fine for e.g. brightness control
- pwmout_period_ms(obj, 20);
- pwmout_write (obj, 0);
-}
-
-void pwmout_free(pwmout_t *obj)
-{
- MBED_ASSERT(obj->pwm != (PWMName)NC);
- PWM_taken[obj->pwm] = 0;
- pwmout_write(obj, 0);
-}
-
-void pwmout_write(pwmout_t *obj, float value)
-{
- uint16_t oldPulseWidth;
-
- NRF_TIMER2->EVENTS_COMPARE[3] = 0;
- NRF_TIMER2->TASKS_STOP = 1;
-
- if (value < 0.0f) {
- value = 0.0;
- } else if (value > 1.0f) {
- value = 1.0;
- }
-
- oldPulseWidth = ACTUAL_PULSE[obj->pwm];
- ACTUAL_PULSE[obj->pwm] = PULSE_WIDTH[obj->pwm] = value * PERIOD;
-
- if (PULSE_WIDTH[obj->pwm] == 0) {
- PULSE_WIDTH[obj->pwm] = 1;
- setModulation(obj, 0, 0);
- } else if (PULSE_WIDTH[obj->pwm] == PERIOD) {
- PULSE_WIDTH[obj->pwm] = PERIOD - 1;
- setModulation(obj, 0, 1);
- } else if ((oldPulseWidth == 0) || (oldPulseWidth == PERIOD)) {
- setModulation(obj, 1, oldPulseWidth == PERIOD);
- }
-
- NRF_TIMER2->INTENSET = TIMER_INTENSET_COMPARE3_Msk;
- NRF_TIMER2->SHORTS = TIMER_SHORTS_COMPARE3_CLEAR_Msk | TIMER_SHORTS_COMPARE3_STOP_Msk;
- NRF_TIMER2->TASKS_START = 1;
-}
-
-float pwmout_read(pwmout_t *obj)
-{
- return ((float)PULSE_WIDTH[obj->pwm] / (float)PERIOD);
-}
-
-void pwmout_period(pwmout_t *obj, float seconds)
-{
- pwmout_period_us(obj, seconds * 1000000.0f);
-}
-
-void pwmout_period_ms(pwmout_t *obj, int ms)
-{
- pwmout_period_us(obj, ms * 1000);
-}
-
-// Set the PWM period, keeping the duty cycle the same.
-void pwmout_period_us(pwmout_t *obj, int us)
-{
- uint32_t periodInTicks = us / TIMER_PRECISION;
-
- NRF_TIMER2->EVENTS_COMPARE[3] = 0;
- NRF_TIMER2->TASKS_STOP = 1;
-
- if (periodInTicks>((1 << 16) - 1)) {
- PERIOD = (1 << 16) - 1; //131ms
- } else if (periodInTicks<5) {
- PERIOD = 5;
- } else {
- PERIOD = periodInTicks;
- }
- NRF_TIMER2->INTENSET = TIMER_INTENSET_COMPARE3_Msk;
- NRF_TIMER2->SHORTS = TIMER_SHORTS_COMPARE3_CLEAR_Msk | TIMER_SHORTS_COMPARE3_STOP_Msk;
- NRF_TIMER2->TASKS_START = 1;
-}
-
-void pwmout_pulsewidth(pwmout_t *obj, float seconds)
-{
- pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
-}
-
-void pwmout_pulsewidth_ms(pwmout_t *obj, int ms)
-{
- pwmout_pulsewidth_us(obj, ms * 1000);
-}
-
-void pwmout_pulsewidth_us(pwmout_t *obj, int us)
-{
- uint32_t pulseInTicks = us / TIMER_PRECISION;
- uint16_t oldPulseWidth = ACTUAL_PULSE[obj->pwm];
-
- NRF_TIMER2->EVENTS_COMPARE[3] = 0;
- NRF_TIMER2->TASKS_STOP = 1;
-
- ACTUAL_PULSE[obj->pwm] = PULSE_WIDTH[obj->pwm] = pulseInTicks;
-
- if (PULSE_WIDTH[obj->pwm] == 0) {
- PULSE_WIDTH[obj->pwm] = 1;
- setModulation(obj, 0, 0);
- } else if (PULSE_WIDTH[obj->pwm] == PERIOD) {
- PULSE_WIDTH[obj->pwm] = PERIOD - 1;
- setModulation(obj, 0, 1);
- } else if ((oldPulseWidth == 0) || (oldPulseWidth == PERIOD)) {
- setModulation(obj, 1, oldPulseWidth == PERIOD);
- }
- NRF_TIMER2->INTENSET = TIMER_INTENSET_COMPARE3_Msk;
- NRF_TIMER2->SHORTS = TIMER_SHORTS_COMPARE3_CLEAR_Msk | TIMER_SHORTS_COMPARE3_STOP_Msk;
- NRF_TIMER2->TASKS_START = 1;
-}