Diff: targets/hal/TARGET_NXP/TARGET_LPC15XX/pwmout_api.c

Revision:

223:d98d59aec21a

Parent:

222:96162ccfbf43

diff -r 96162ccfbf43 -r d98d59aec21a targets/hal/TARGET_NXP/TARGET_LPC15XX/pwmout_api.c
--- a/targets/hal/TARGET_NXP/TARGET_LPC15XX/pwmout_api.c	Fri Jun 06 11:00:08 2014 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,173 +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"
-
-static LPC_SCT0_Type *SCTs[4] = {
-    (LPC_SCT0_Type*)LPC_SCT0,
-    (LPC_SCT0_Type*)LPC_SCT1,
-    (LPC_SCT0_Type*)LPC_SCT2,
-    (LPC_SCT0_Type*)LPC_SCT3,
-};
-
-// bit flags for used SCTs
-static unsigned char sct_used = 0;
-static int get_available_sct(void) {
-    int i;
-    for (i=0; i<4; i++) {
-        if ((sct_used & (1 << i)) == 0)
-            return i;
-    }
-    return -1;
-}
-
-void pwmout_init(pwmout_t* obj, PinName pin) {
-	if (pin == (uint32_t)NC)
-		error("PwmOut pin mapping failed");
-	
-    int sct_n = get_available_sct();
-    if (sct_n == -1) {
-        error("No available SCT");
-    }
-    
-    sct_used |= (1 << sct_n);
-    obj->pwm =  SCTs[sct_n];
-    obj->pwm_ch = sct_n;
-
-    LPC_SCT0_Type* pwm = obj->pwm;
-
-    // Enable the SCT clock
-    LPC_SYSCON->SYSAHBCLKCTRL1 |= (1 << (obj->pwm_ch + 2));
-
-    // Clear peripheral reset the SCT:
-    LPC_SYSCON->PRESETCTRL1 |=  (1 << (obj->pwm_ch + 2));
-    LPC_SYSCON->PRESETCTRL1 &= ~(1 << (obj->pwm_ch + 2));
-    
-    switch(obj->pwm_ch) {
-    	case 0:
-            // SCT0_OUT0
-            LPC_SWM->PINASSIGN[7] &= ~0x0000FF00;
-            LPC_SWM->PINASSIGN[7] |= (pin << 8);
-    		break;
-    	case 1:
-            // SCT1_OUT0
-            LPC_SWM->PINASSIGN[8] &= ~0x000000FF;
-            LPC_SWM->PINASSIGN[8] |= (pin);
-    		break;
-    	case 2:
-            // SCT2_OUT0
-            LPC_SWM->PINASSIGN[8] &= ~0xFF000000;
-            LPC_SWM->PINASSIGN[8] |= (pin << 24);
-    		break;
-    	case 3:
-            // SCT3_OUT0
-            LPC_SWM->PINASSIGN[9] &= ~0x00FF0000;
-            LPC_SWM->PINASSIGN[9] |= (pin << 16);
-    		break;
-    	default:
-    		break;
-    }
-    
-    // Two 16-bit counters, autolimit
-    pwm->CONFIG &= ~(0x1);
-    pwm->CONFIG |= (1 << 17);
-    
-    // halt and clear the counter
-    pwm->CTRL |= (1 << 2) | (1 << 3);
-    
-    // System Clock -> us_ticker (1)MHz
-    pwm->CTRL &= ~(0x7F << 5);
-    pwm->CTRL |= (((SystemCoreClock/1000000 - 1) & 0x7F) << 5);
-    
-    // Match reload register
-    pwm->MATCHREL0 = 20000; // 20ms
-    pwm->MATCHREL1 = (pwm->MATCHREL0 / 4); // 50% duty
-    
-    pwm->OUT0_SET = (1 << 0); // event 0
-    pwm->OUT0_CLR = (1 << 1); // event 1
-
-	pwm->EV0_CTRL  = (1 << 12);
-	pwm->EV0_STATE = 0xFFFFFFFF;
-	pwm->EV1_CTRL  = (1 << 12) | (1 << 0);
-	pwm->EV1_STATE = 0xFFFFFFFF;
-
-    // unhalt the counter:
-    //    - clearing bit 2 of the CTRL register
-    pwm->CTRL &= ~(1 << 2);
-
-    // 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) {
-    // Disable the SCT clock
-    LPC_SYSCON->SYSAHBCLKCTRL1 &= ~(1 << (obj->pwm_ch + 2));
-    sct_used &= ~(1 << obj->pwm_ch);
-}
-
-void pwmout_write(pwmout_t* obj, float value) {
-    LPC_SCT0_Type* pwm = obj->pwm;
-    if (value < 0.0f) {
-        value = 0.0;
-    } else if (value > 1.0f) {
-        value = 1.0;
-    }
-    uint32_t t_off = pwm->MATCHREL0 - (uint32_t)((float)(pwm->MATCHREL0) * value);
-    uint32_t t_on = (uint32_t)((float)(pwm->MATCHREL0) * value);
-    pwm->MATCHREL1 = t_on;
-}
-
-float pwmout_read(pwmout_t* obj) {
-    uint32_t t_off = obj->pwm->MATCHREL0;
-    uint32_t t_on  = obj->pwm->MATCHREL1;
-	float v = (float)t_on/(float)t_off;
-    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) {
-    LPC_SCT0_Type* pwm = obj->pwm;
-    uint32_t t_off = pwm->MATCHREL0;
-    uint32_t t_on  = pwm->MATCHREL1;
-	float v = (float)t_on/(float)t_off;
-    pwm->MATCHREL0 = (uint64_t)us;
-    pwm->MATCHREL1 = (uint64_t)((float)us * (float)v);
-}
-
-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->pwm->MATCHREL1 = (uint64_t)us;
-}
-