[K64F] Ensure immediate update of CnV register in FTM

Also changed pin assignment for the PWM test.

Author: Bogdan Marinescu

libraries/mbed/targets/hal/TARGET_Freescale/TARGET_KPSDK_MCUS/TARGET_K64F/pwmout_api.c

@@ -116,15 +116,19 @@ void pwmout_free(pwmout_t* obj) {
 }
 
 void pwmout_write(pwmout_t* obj, float value) {
+    uint32_t instance = obj->pwm_name >> TPM_SHIFT;
     if (value < 0.0f) {
         value = 0.0f;
     } else if (value > 1.0f) {
         value = 1.0f;
     }
-    uint16_t mod = ftm_hal_get_mod(obj->pwm_name >> TPM_SHIFT);
+    uint16_t mod = ftm_hal_get_mod(instance);
     uint32_t new_count = (uint32_t)((float)(mod) * value);
-    ftm_hal_set_channel_count_value(obj->pwm_name >> TPM_SHIFT, obj->pwm_name & 0xF, new_count);
-    ftm_hal_set_counter(obj->pwm_name >> TPM_SHIFT, 0);
+    // Stop FTM clock to ensure instant update of MOD register
+    ftm_hal_set_clock_source(instance, kClock_source_FTM_None);
+    ftm_hal_set_channel_count_value(instance, obj->pwm_name & 0xF, new_count);
+    ftm_hal_set_counter(instance, 0);
+    ftm_hal_set_clock_source(instance, kClock_source_FTM_SystemClk);
 }
 
 float pwmout_read(pwmout_t* obj) {

libraries/tests/mbed/pwm/main.cpp

@@ -18,7 +18,7 @@ float value = 0.75;
 
 int main() {
 #if defined(TARGET_FF_ARDUINO)
-    PwmOut pwm(D5);
+    PwmOut pwm(D9);
 
     pwm.period_ms(10);
     pwm.write(value);