Diff: targets/hal/TARGET_NXP/TARGET_LPC11UXX/pwmout_api.c

Revision:

43:b3acfef78949

Parent:

42:7ca0bbba899b

--- a/targets/hal/TARGET_NXP/TARGET_LPC11UXX/pwmout_api.c	Sun Oct 27 16:30:04 2013 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,183 +0,0 @@
-/* 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"
-
-#define TCR_CNT_EN       0x00000001
-#define TCR_RESET        0x00000002
-
-/* To have a PWM where we can change both the period and the duty cycle,
- * we need an entire timer. With the following conventions:
- *   * MR3 is used for the PWM period
- *   * MR0, MR1, MR2 are used for the duty cycle
- */
-static const PinMap PinMap_PWM[] = {
-    /* CT16B0 */
-    {P0_8 , PWM_1, 2}, {P1_13, PWM_1, 2},    /* MR0 */
-    {P0_9 , PWM_2, 2}, {P1_14, PWM_2, 2},   /* MR1 */
-    {P0_10, PWM_3, 3}, {P1_15, PWM_3, 2},   /* MR2 */
-
-    /* CT16B1 */
-    {P0_21, PWM_4, 1},                      /* MR0 */
-    {P0_22, PWM_5, 2}, {P1_23, PWM_5, 1},   /* MR1 */
-
-    /* CT32B0 */
-    {P0_18, PWM_6, 2}, {P1_24, PWM_6, 1},   /* MR0 */
-    {P0_19, PWM_7, 2}, {P1_25, PWM_7, 1},   /* MR1 */
-    {P0_1 , PWM_8, 2}, {P1_26, PWM_8, 1},   /* MR2 */
-
-    /* CT32B1 */
-    {P0_13, PWM_9 , 3}, {P1_0, PWM_9 , 1},  /* MR0 */
-    {P0_14, PWM_10, 3}, {P1_1, PWM_10, 1},  /* MR1 */
-    {P0_15, PWM_11, 3}, {P1_2, PWM_11, 1},  /* MR2 */
-
-    {NC, NC, 0}
-};
-
-typedef struct {
-    uint8_t timer;
-    uint8_t mr;
-} timer_mr;
-
-static timer_mr pwm_timer_map[11] = {
-    {0, 0}, {0, 1}, {0, 2},
-    {1, 0}, {1, 1},
-    {2, 0}, {2, 1}, {2, 2},
-    {3, 0}, {3, 1}, {3, 2},
-};
-
-static LPC_CTxxBx_Type *Timers[4] = {
-    LPC_CT16B0, LPC_CT16B1,
-    LPC_CT32B0, LPC_CT32B1
-};
-
-static unsigned int pwm_clock_mhz;
-
-void pwmout_init(pwmout_t* obj, PinName pin) {
-    // determine the channel
-    PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
-    if (pwm == (PWMName)NC)
-        error("PwmOut pin mapping failed");
-    
-    obj->pwm = pwm;
-    
-    // Timer registers
-    timer_mr tid = pwm_timer_map[pwm];
-    LPC_CTxxBx_Type *timer = Timers[tid.timer];
-    
-    // Disable timer
-    timer->TCR = 0;
-    
-    // Power the correspondent timer
-    LPC_SYSCON->SYSAHBCLKCTRL |= 1 << (tid.timer + 7);
-    
-    /* Enable PWM function */
-    timer->PWMC = (1 << 3)|(1 << 2)|(1 << 1)|(1 << 0);
-    
-    /* Reset Functionality on MR3 controlling the PWM period */
-    timer->MCR = 1 << 10;
-    
-    pwm_clock_mhz = SystemCoreClock / 1000000;
-    
-    // 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) {
-    // [TODO]
-}
-
-void pwmout_write(pwmout_t* obj, float value) {
-    if (value < 0.0f) {
-        value = 0.0;
-    } else if (value > 1.0f) {
-        value = 1.0;
-    }
-    
-    timer_mr tid = pwm_timer_map[obj->pwm];
-    LPC_CTxxBx_Type *timer = Timers[tid.timer];
-    uint32_t t_off = timer->MR3 - (uint32_t)((float)(timer->MR3) * value);
-    
-    timer->TCR = TCR_RESET;
-    timer->MR[tid.mr] = t_off;
-    timer->TCR = TCR_CNT_EN;
-}
-
-float pwmout_read(pwmout_t* obj) {
-    timer_mr tid = pwm_timer_map[obj->pwm];
-    LPC_CTxxBx_Type *timer = Timers[tid.timer];
-    
-    float v = (float)(timer->MR3 - timer->MR[tid.mr]) / (float)(timer->MR3);
-    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) {
-    int i = 0;
-    uint32_t period_ticks = pwm_clock_mhz * us;
-    
-    timer_mr tid = pwm_timer_map[obj->pwm];
-    LPC_CTxxBx_Type *timer = Timers[tid.timer];
-    uint32_t old_period_ticks = timer->MR3;
-    
-    timer->TCR = TCR_RESET;
-    timer->MR3 = period_ticks;
-    
-    // Scale the pulse width to preserve the duty ratio
-    if (old_period_ticks > 0) {
-        for (i=0; i<3; i++) {
-            uint32_t t_off = period_ticks - (uint32_t)(((uint64_t)timer->MR[i] * (uint64_t)period_ticks) / (uint64_t)old_period_ticks);
-            timer->MR[i] = t_off;
-        }
-    }
-    timer->TCR = TCR_CNT_EN;
-}
-
-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 t_on = (uint32_t)(((uint64_t)SystemCoreClock * (uint64_t)us) / (uint64_t)1000000);
-    timer_mr tid = pwm_timer_map[obj->pwm];
-    LPC_CTxxBx_Type *timer = Timers[tid.timer];
-    
-    timer->TCR = TCR_RESET;
-    if (t_on > timer->MR3) {
-        pwmout_period_us(obj, us);
-    }
-    uint32_t t_off = timer->MR3 - t_on;
-    timer->MR[tid.mr] = t_off;
-    timer->TCR = TCR_CNT_EN;
-}