mbed library sources
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Diff: vendor/Freescale/KL25Z/hal/pwmout_api.c
- Revision:
- 10:3bc89ef62ce7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/vendor/Freescale/KL25Z/hal/pwmout_api.c Fri Jun 14 17:49:17 2013 +0100 @@ -0,0 +1,121 @@ +/* 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_9 , 3}, // PTB18, TPM2 CH0 + {LED_GREEN, PWM_10, 3}, // PTB19, TPM2 CH1 + {LED_BLUE , PWM_2 , 4}, // PTD1 , TPM0 CH1 + + // Arduino digital pinout + {D0, PWM_9 , 3}, // PTA1 , TPM2 CH0 + {D1, PWM_10, 3}, // PTA2 , TPM2 CH1 + {D2, PWM_5 , 4}, // PTD4 , TPM0 CH4 + {D3, PWM_7 , 3}, // PTA12, TPM1 CH0 + {D4, PWM_2 , 3}, // PTA4 , TPM0 CH1 + {D5, PWM_3 , 3}, // PTA5 , TPM0 CH2 + {D6, PWM_5 , 3}, // PTC8 , TPM0 CH4 + {D7, PWM_6 , 3}, // PTC9 , TPM0 CH5 + {D8, PWM_8 , 3}, // PTA13, TPM1 CH1 + {D9, PWM_6 , 4}, // PTD5 , TPM0 CH5 + {D10, PWM_1 , 4}, // PTD0 , TPM0 CH0 + {D11, PWM_3 , 4}, // PTD2 , TPM0 CH2 + {D12, PWM_4 , 4}, // PTD3 , TPM0 CH3 + {D13, PWM_2 , 4}, // PTD1 , TPM0 CH1 + {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; +}