Diff: targets/hal/TARGET_Freescale/TARGET_K20D5M/pwmout_api.c

Revision:

68:41613245dfd7

Child:

73:299c67215126

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/hal/TARGET_Freescale/TARGET_K20D5M/pwmout_api.c	Thu Dec 26 13:00:06 2013 +0000
@@ -0,0 +1,119 @@
+/* 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_3 , 3}, // PTC3, FTM0 CH2
+    {LED_GREEN, PWM_5, 3},  // PTD4, FTM0 CH4
+    {LED_BLUE , PWM_9 , 3}, // PTA2 , FTM0 CH7
+
+    // Arduino digital pinout
+    {D3,  PWM_5 , 3}, // PTD4, FTM0 CH4
+    {D5,  PWM_7 , 3}, // PTA1 , FTM0 CH6
+    {D6,  PWM_3 , 3}, // PTC3 , FTM0 CH2
+    {D9,  PWM_8 , 4}, // PTD2 , FTM0 CH7
+    {D10, PWM_2 , 4}, // PTC2 , FTM0 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 == (PWMName)NC)
+        error("PwmOut pin mapping failed");
+
+    unsigned int port = (unsigned int)pin >> PORT_SHIFT;
+    unsigned int ftm_n = (pwm >> TPM_SHIFT);
+    unsigned int ch_n = (pwm & 0xFF);
+
+    SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port);
+    SIM->SCGC6 |= 1 << (SIM_SCGC6_FTM0_SHIFT + ftm_n);
+
+    FTM_Type *ftm = (FTM_Type *)(FTM0_BASE + 0x1000 * ftm_n);
+    ftm->MODE |= FTM_MODE_WPDIS_MASK; //write protection disabled
+    ftm->CONF |= FTM_CONF_BDMMODE(3);
+    ftm->SC = FTM_SC_CLKS(1) | FTM_SC_PS(6); // (48)MHz / 64 = (0.75)MHz
+    ftm->CONTROLS[ch_n].CnSC = (FTM_CnSC_MSB_MASK | FTM_CnSC_ELSB_MASK); /* No Interrupts; High True pulses on Edge Aligned PWM */
+    ftm->PWMLOAD |= FTM_PWMLOAD_LDOK_MASK; //loading updated values enabled
+    //ftm->SYNCONF |= FTM_SYNCONF_SWRSTCNT_MASK;
+    ftm->MODE |= FTM_MODE_INIT_MASK;
+
+    obj->CnV = &ftm->CONTROLS[ch_n].CnV;
+    obj->MOD = &ftm->MOD;
+    obj->CNT = &ftm->CNT;
+    obj->SYNC = &ftm->SYNC;
+
+    // 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;
+    //*obj->SYNC |= FTM_SYNC_SWSYNC_MASK;
+}
+
+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;
+}