PWM输入测量值不确定

tify;text-indent: 40px;">大家好，

我想使用TIM1及其PWM输入模式来获得STM8S003上测量信号的占空比和频率。但我对测量值存在不确定性。


代码片段
void initialization（）{
//系统时钟：
CLK_CKDIVR_HSIDIV = 3; // fMASTER = fHSI / 8 = 16/8 = 2MHz


CLK_CKDIVR_CPUDIV = 0; // fCPU = fMASTER = 2 MHz


CLK_PCKENR1_TIM1 = 1;




//定时器1
TIM1_PSCRH = 0x00;
TIM1_PSCRL = 0x01; // fTIM1 = fMASTER /（TIM1_PSCR + 1）= 1 MHz

TIM1_CR1_UDIS = 0;
TIM1_CR1_ARPE = 1;
TIM1_IER_CC1IE = 1;
TIM1_IER_CC2IE = 1;


//值根据RM0016参考手册，p。设置。 169 PWM输入信号测量 - 程序
TIM1_CCMR1_CC1S = 1;
TIM1_CCER1_CC1P = 0;
TIM1_CCMR2_CC2S = 2;
TIM1_CCER1_CC2P = 1;
TIM1_SMCR_TS = 5;
TIM1_SMCR_SMS = 4;
TIM1_CCER1_CC1E = 1;
TIM1_CCER1_CC2E = 1;
TIM1_CR1_CEN = 1; //启动计时器
}


@interrupt void PWM_vIsrHandleTimer1CaptureEvent（void）// irq12
{
if（TIM1_SR1_UIF）{
TIM1_SR1_UIF = 0;
//永远不会发生
}

if（TIM1_SR1_CC1IF）{
TIM1_SR1_CC1IF = 0; //从TIM1_CCR1L读取应该这样做

dutyCycleInTicks =（TIM1_CCR1H 以下为原文




Hello all,

I want to use TIM1 and its PWM input mode to obtain duty cycle and frequency of measured signal on STM8S003. But I have uncertainty about measured value.


Snippets of code
void initialization () {
//System Clocks:
CLK_CKDIVR_HSIDIV = 3; // fMASTER = fHSI / 8 = 16/8 = 2MHz


CLK_CKDIVR_CPUDIV = 0; // fCPU = fMASTER  = 2 MHz


CLK_PCKENR1_TIM1 = 1;




//Timer1
TIM1_PSCRH = 0x00;
TIM1_PSCRL = 0x01; // fTIM1 = fMASTER / (TIM1_PSCR + 1) = 1 MHz
  
TIM1_CR1_UDIS = 0;  
TIM1_CR1_ARPE = 1;  
TIM1_IER_CC1IE = 1;  
TIM1_IER_CC2IE = 1;


// Values are set according to RM0016 Reference manual, p. 169 PWM input signal measurement - Procedure
TIM1_CCMR1_CC1S = 1;
TIM1_CCER1_CC1P = 0;
TIM1_CCMR2_CC2S = 2;
TIM1_CCER1_CC2P = 1;
TIM1_SMCR_TS = 5;
TIM1_SMCR_SMS = 4;
TIM1_CCER1_CC1E = 1;
TIM1_CCER1_CC2E = 1;
TIM1_CR1_CEN = 1;  //start The Timer
}


@interrupt void PWM_vIsrHandleTimer1CaptureEvent(void) // irq12
{
if(TIM1_SR1_UIF) {
TIM1_SR1_UIF = 0;
// never occur
}
  
if(TIM1_SR1_CC1IF) {
TIM1_SR1_CC1IF = 0; //  read from TIM1_CCR1L should do this
dutyCycleInTicks = (TIM1_CCR1H << 8) & 0xFF00;
dutyCycleInTicks |= (TIM1_CCR1L & 0xFF);
}
  
if(TIM1_SR1_CC2IF) {
TIM1_SR1_CC2IF = 0;
periodInTicks = (TIM1_CCR2H << 8) & 0xFF00;
periodInTicks |= (TIM1_CCR2L & 0xFF);
}


Is it sufficient to use only this functions (+enable interrupt and etc) or something I am missing in work with Timers (reseting counter or?). Problem is why values are not related to input clock to TIM1. If I change TIM1_PSCRx prescaler or CLK_CKDIVR_HSIDIV (input clock to Tim1 peripheral), measured numbers are stilt the same. Generated PWM attached to TIM1_CH1 pin can vary in frequency, but value of TIM1_CCR1 is still same (4000), and TIM1_CCR2 is OK - change depends on duty cycle (for 50% it is 2000)... What am I missing?
Thanks, Regards


  
#pwm-stm8