Does STM32 timer frequency equal the PWM output frequency? - c

Question

I have easy understanding Question. Whet I do initialize my STM32 timer for 1 sek counts (TIM8, Prescaller = 16800-1, Period = 10000-1) and want to debug it (measure a pin output frequency) - it a timer frequency the same frequency like I can observe it on oscilloscope?
And it is a right configuration for TIM8 timer Interrupt?
void Second_timer_Init() {
GPIO_InitTypeDef GPIO_InitStructure; //GPIO Init structure definition
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE); //Enables AHB1 peripheral clock for GPIOC
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE); //Enables AHB1 peripheral clock for TIM2
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; //Specifies the GPIO pins to be configured
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //Specifies the operating output type for the selected pins
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; //GPIO Alternate function Mode
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //Specifies the operating Pull-up/Pull down for the selected pins
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //Specifies the speed for the selected pins
GPIO_Init(GPIOC, &GPIO_InitStructure); //Initializes the GPIOA peripheral
TIM_TimeBaseInitTypeDef Timer_InitStructure; //TIM8 Time Base Init structure definition
TIM_OCInitTypeDef Output_ChannelInit; //TIM8 Output Compare Init structure definition
GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_TIM8); // PC6 -> Connect TIM8 pins to AF3
Timer_InitStructure.TIM_Period = 10000 - 1; //Specifies the period value (Orig 1 Sek: 10000-1)
Timer_InitStructure.TIM_Prescaler = 16800-1; //Specifies the prescaler value used to divide the TIM clock (Orig 1 Sek: 16800-1)
Timer_InitStructure.TIM_ClockDivision = TIM_CKD_DIV1; //Specifies the clock division (0)
Timer_InitStructure.TIM_CounterMode = TIM_CounterMode_Up; //Specifies the counter mode
TIM_TimeBaseInit(TIM8, &Timer_InitStructure); //Initializes the TIM8 Time Base Unit peripheral
// TIM_OCStructInit(&Output_ChannelInit);
Output_ChannelInit.TIM_OCMode = TIM_OCMode_PWM1; //Specifies the TIM8 PWM mode
Output_ChannelInit.TIM_OutputState = TIM_OutputState_Enable;//Specifies the TIM8 Output Compare state
Output_ChannelInit.TIM_Pulse = 0; //Specifies the pulse value to be loaded into the Capture Compare Register
Output_ChannelInit.TIM_OCPolarity = TIM_OCPolarity_Low; //Specifies the output polarity
TIM_OC1Init(TIM8, &Output_ChannelInit); //Initializes the TIM8 Channel1
TIM_OC1PreloadConfig(TIM8, TIM_OCPreload_Enable); //Enables the TIM2 peripheral Preload register on CCR1
TIM_ARRPreloadConfig(TIM8, ENABLE); //Enables TIM2 peripheral Preload register on ARR
TIM_Cmd(TIM8, ENABLE); //Enables the specified TIM8 peripheral
TIM_CtrlPWMOutputs(TIM8, ENABLE); //Enables the TIM peripheral Main Outputs ?
TIM8->CCR1 = 5000; //Set duty cycle to 50%
TIM_ClearITPendingBit(TIM8, TIM_IT_Update); //Clears the TIM8 interrupt pending bits
TIM_ITConfig(TIM8, TIM_IT_Update, ENABLE); //Enables the specified TIM8 interrupts
NVIC_InitTypeDef NVIC_InitStructure; //NVIC Init Structure definition
NVIC_InitStructure.NVIC_IRQChannel = TIM8_CC_IRQn; //Specifies the IRQ channel to be enabled
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;//Specifies the pre-emption priority for the IRQ channel specified in NVIC_IRQChannel (0-15)
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00; //Specifies the subpriority level for the IRQ channel specified in NVIC_IRQChannel (0-15)
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //Specifies whether the IRQ channel defined in NVIC_IRQChannel will be enabled
NVIC_Init(&NVIC_InitStructure); //Initializes the NVIC peripheral
}
IRQ Handler
void TIM8_CC_IRQHandler(){
if (TIM_GetITStatus(TIM8, TIM_IT_Update) != RESET) //Checks whether the TIM8 interrupt has occurred
{
TIM_ClearITPendingBit(TIM8, TIM_IT_Update); //Clears the TIM8 interrupt pending bits
TIM3->CCR1 = 500; //Debug
}
else{
TIM3->CCR1 = 0; //Debug
}
}

Answer 1

As I see you change the TIM3 registers in the TIM8 interrupt.
Secondly you check for the wrong event in your interrupt routine (this routine is invoked then the CC event occurs not the UG event. Same when you set the interrupts. You enable the UG interrupt but serve the CC one. Some of the uC models have those interrupt vectors shared some not.
BTW What is the point of using HAL library if you change the registers?