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--- en:edu:zmitac:s2:aih:lab:stm32pwm [2024/01/13 20:28] – ktokarz
+++ en:edu:zmitac:s2:aih:lab:stm32pwm [2024/01/16 09:11] (current) – ktokarz
@@ Line 10: / Line 10: @@
 </table>
 At the beginning of the code, there is a definition of pin value. Although the P-Nucleo-WB55 has the LED_BUILTIN defined it can't work as the PMW timer output. We have to override it.
-<code>
+<code c>
 // *********************************************************
 #define LED_BUILTIN D6 //Override of the default LED_BUILTIN
@@ Line 21: / Line 21: @@
 </code>
 In the setup part of the code, the program automatically retrieves the timer instance and PWM channel number connected to the previously defined pin.
-<code>
+<code c>
   TIM_TypeDef *Instance = (TIM_TypeDef *)pinmap_peripheral(digitalPinToPinName(pin), PinMap_PWM);
   uint32_t channel = STM_PIN_CHANNEL(pinmap_function(digitalPinToPinName(pin), PinMap_PWM));
 </code>
 While having information on the timer instance and channel number it instantiates the HardwareTimer object.
-<code>
+<code c>
  HardwareTimer *MyTim = new HardwareTimer(Instance);
 </code>
 The setup function oi finished with starting the timer to operate in PMW mode and configuring the PWM signal with frequency and duty cycle.
-<code>
+<code c>
   MyTim->setPWM(channel, pin, 5, 10); // 5 Hertz, 10% dutycycle
 </code>
 It is possible to modify the duty cycle by changing the current value of the capture and compare register for specified channel. To do it we need to use the function.
-<code>
+<code c>
   MyTim->setCaptureCompare(channel, 50, PERCENT_COMPARE_FORMAT); // 50%
 </code>
-The program that controls all three LEDs has two files shown below PwmLedTest.h and PwmLedTest.cpp.
-===== PwmLedTest.h =====
-<code>
-#include "Arduino.h"
-#include <HardwareTimer.h>
-#ifndef _PWMLED_TestLib
-#define _PWMLED_TestLib
-// Pins definition for RGB LED
-#define LED_PWM_RED   D3  //Arduino numberring D3, STM numberring PA_10
-#define LED_PWM_GREEN D6  //Arduino numberring D6, STM numberring PA_8
-#define LED_PWM_BLUE  D9  //Arduino numberring D9, STM numberring PA_9
-// PWM variables definitions
-HardwareTimer *MyTimLED;               //Hardware Timer for PWM
-uint32_t channelR, channelG, channelB; //RGB cahnnels
-#endif
-</code>
-===== PwmLedTest.cpp =====
-<code>
-  #include "PwmLedTest.h"
-  void PwmLedSetup()
-  {
-    //Create Timer instance type based on the servo pin (the same timer is used for fan).
-    TIM_TypeDef *Instance = (TIM_TypeDef *)pinmap_peripheral(digitalPinToPinName(LED_PWM_RED), PinMap_PWM);
-    //Define two separate channels for servo and fan
-    channelR = STM_PIN_CHANNEL(pinmap_function(digitalPinToPinName(LED_PWM_RED), PinMap_PWM));
-    channelG = STM_PIN_CHANNEL(pinmap_function(digitalPinToPinName(LED_PWM_GREEN), PinMap_PWM));
-    channelB = STM_PIN_CHANNEL(pinmap_function(digitalPinToPinName(LED_PWM_BLUE), PinMap_PWM));
-    // Instantiate HardwareTimer object. Thanks to 'new' instantiation, HardwareTimer is not destructed when setup() function is finished.
-    MyTimLED = new HardwareTimer(Instance);
-    // Configure and start PWM
-    MyTimLED->setPWM(channelR,LED_PWM_RED,100,1);   /* 100 Hertz, 1% dutycycle. */
-    MyTimLED->setPWM(channelG,LED_PWM_GREEN,100,1); /* 100 Hertz, 1% dutycycle. */
-    MyTimLED->setPWM(channelB,LED_PWM_BLUE,100,1);  /* 100 Hertz, 1% dutycycle. */
-  }
-  void fRGBLEDSet(int red, int green, int blue)
-  {
-    MyTimLED->setCaptureCompare(channelR, red, PERCENT_COMPARE_FORMAT);   //modify duty cycle
-    MyTimLED->setCaptureCompare(channelG, green, PERCENT_COMPARE_FORMAT); //modify duty cycle
-    MyTimLED->setCaptureCompare(channelB, blue, PERCENT_COMPARE_FORMAT);  //modify duty cycle
-  }
-</code>