mbed library sources: Modified to operate FRDM-KL25Z at 48MHz from internal 32kHz oscillator (nothing else changed).
Fork of mbed-src by
The only file that changed is: mbed-src-FLL48/targets/cmsis/TARGET_Freescale/TARGET_KL25Z/system_MKL25Z4.h
targets/hal/TARGET_Freescale/TARGET_KL05Z/pwmout_api.c
- Committer:
- bogdanm
- Date:
- 2013-09-10
- Revision:
- 20:4263a77256ae
File content as of revision 20:4263a77256ae:
/* 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 "pwmout_api.h" #include "cmsis.h" #include "pinmap.h" #include "error.h" static const PinMap PinMap_PWM[] = { // LEDs {LED_RED , PWM_4 , 2}, // PTB8 , TPM0 CH3 {LED_GREEN, PWM_3, 2}, // PTB9 , TPM0 CH2 {LED_BLUE , PWM_2 , 2}, // PTB10, TPM0 CH1 // Arduino digital pinout {D3, PWM_8 , 2}, // PTB5 , TPM1 CH1 {D5, PWM_7 , 2}, // PTA12, TPM1 CH0 {D6, PWM_4 , 2}, // PTB6 , TPM0 CH3 {D7, PWM_3 , 2}, // PTB7 , TPM0 CH2 {D8, PWM_2 , 2}, // PTB10, TPM0 CH1 {D9, PWM_1 , 2}, // PTB11, TPM0 CH0 {D10, PWM_6 , 2}, // PTA5 , TPM0 CH5 {D12, PWM_5 , 2}, // PTA6 , TPM0 CH4 {NC , NC , 0} }; #define PWM_CLOCK_MHZ (0.75) // (48)MHz / 64 = (0.75)MHz void pwmout_init(pwmout_t* obj, PinName pin) { // determine the channel PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM); if (pwm == (uint32_t)NC) { error("PwmOut pin mapping failed"); } unsigned int port = (unsigned int)pin >> PORT_SHIFT; unsigned int tpm_n = (pwm >> TPM_SHIFT); unsigned int ch_n = (pwm & 0xFF); SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port); SIM->SCGC6 |= 1 << (SIM_SCGC6_TPM0_SHIFT + tpm_n); SIM->SOPT2 |= SIM_SOPT2_TPMSRC(1); // Clock source: MCGFLLCLK or MCGPLLCLK TPM_Type *tpm = (TPM_Type *)(TPM0_BASE + 0x1000 * tpm_n); tpm->SC = TPM_SC_CMOD(1) | TPM_SC_PS(6); // (48)MHz / 64 = (0.75)MHz tpm->CONTROLS[ch_n].CnSC = (TPM_CnSC_MSB_MASK | TPM_CnSC_ELSB_MASK); // No Interrupts; High True pulses on Edge Aligned PWM obj->CnV = &tpm->CONTROLS[ch_n].CnV; obj->MOD = &tpm->MOD; obj->CNT = &tpm->CNT; // default to 20ms: standard for servos, and fine for e.g. brightness control pwmout_period_ms(obj, 20); pwmout_write(obj, 0); // Wire pinout pinmap_pinout(pin, PinMap_PWM); } void pwmout_free(pwmout_t* obj) { } void pwmout_write(pwmout_t* obj, float value) { if (value < 0.0) { value = 0.0; } else if (value > 1.0) { value = 1.0; } *obj->CnV = (uint32_t)((float)(*obj->MOD) * value); *obj->CNT = 0; } float pwmout_read(pwmout_t* obj) { float v = (float)(*obj->CnV) / (float)(*obj->MOD); return (v > 1.0) ? (1.0) : (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) { float dc = pwmout_read(obj); *obj->MOD = PWM_CLOCK_MHZ * us; pwmout_write(obj, dc); } 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) { *obj->CnV = PWM_CLOCK_MHZ * us; }