mbed library sources
Dependents: frdm_kl05z_gpio_test
Fork of mbed-src by
targets/hal/TARGET_Freescale/TARGET_KPSDK_MCUS/TARGET_MCU_K64F/pwmout_api.c
- Committer:
- shaoziyang
- Date:
- 2014-09-13
- Revision:
- 323:9e901b0a5aa1
- Parent:
- 320:be04b2b1e3f2
File content as of revision 323:9e901b0a5aa1:
/* mbed Microcontroller Library * Copyright (c) 2006-2013 ARM Limited * * 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" #if DEVICE_PWMOUT #include "cmsis.h" #include "pinmap.h" #include "fsl_ftm_hal.h" #include "fsl_mcg_hal.h" #include "fsl_clock_manager.h" #include "PeripheralPins.h" static float pwm_clock_mhz; void pwmout_init(pwmout_t* obj, PinName pin) { PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM); MBED_ASSERT(pwm != (PWMName)NC); obj->pwm_name = pwm; uint32_t pwm_base_clock; clock_manager_get_frequency(kBusClock, &pwm_base_clock); float clkval = (float)pwm_base_clock / 1000000.0f; uint32_t clkdiv = 0; while (clkval > 1) { clkdiv++; clkval /= 2.0f; if (clkdiv == 7) { break; } } pwm_clock_mhz = clkval; uint32_t channel = pwm & 0xF; uint32_t instance = pwm >> TPM_SHIFT; clock_manager_set_gate(kClockModuleFTM, instance, true); ftm_hal_set_tof_frequency(instance, 3); ftm_hal_set_clock_source(instance, kClock_source_FTM_SystemClk); ftm_hal_set_clock_ps(instance, (ftm_clock_ps_t)clkdiv); ftm_hal_set_counter_init_val(instance, 0); // default to 20ms: standard for servos, and fine for e.g. brightness control pwmout_period_ms(obj, 20); pwmout_write (obj, 0); ftm_config_t config = { .mode = kFtmEdgeAlignedPWM, .channel = channel, .edge_mode = {.ftm_pwm_edge_mode = kFtmHighTrue} }; ftm_hal_enable_pwm_mode(instance, &config); // Wire pinout pinmap_pinout(pin, PinMap_PWM); } void pwmout_free(pwmout_t* obj) { } void pwmout_write(pwmout_t* obj, float value) { uint32_t instance = obj->pwm_name >> TPM_SHIFT; if (value < 0.0f) { value = 0.0f; } else if (value > 1.0f) { value = 1.0f; } uint16_t mod = ftm_hal_get_mod(instance); uint32_t new_count = (uint32_t)((float)(mod) * value); // Stop FTM clock to ensure instant update of MOD register ftm_hal_set_clock_source(instance, kClock_source_FTM_None); ftm_hal_set_channel_count_value(instance, obj->pwm_name & 0xF, new_count); ftm_hal_set_counter(instance, 0); ftm_hal_set_clock_source(instance, kClock_source_FTM_SystemClk); } float pwmout_read(pwmout_t* obj) { uint16_t count = ftm_hal_get_channel_count_value(obj->pwm_name >> TPM_SHIFT, obj->pwm_name & 0xF, 0); uint16_t mod = ftm_hal_get_mod(obj->pwm_name >> TPM_SHIFT); if (mod == 0) return 0.0; float v = (float)(count) / (float)(mod); return (v > 1.0f) ? (1.0f) : (v); } 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 instance = obj->pwm_name >> TPM_SHIFT; float dc = pwmout_read(obj); // Stop FTM clock to ensure instant update of MOD register ftm_hal_set_clock_source(instance, kClock_source_FTM_None); ftm_hal_set_mod(instance, (uint32_t)(pwm_clock_mhz * (float)us) - 1); pwmout_write(obj, dc); ftm_hal_set_clock_source(instance, kClock_source_FTM_SystemClk); } 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 value = (uint32_t)(pwm_clock_mhz * (float)us); ftm_hal_set_channel_count_value(obj->pwm_name >> TPM_SHIFT, obj->pwm_name & 0xF, value); } #endif