F334 HRTImer reset from TIM2

[tobias239955_stm1]

Posted on January 26, 2015 at 17:09

Hi,

I need to generate a Signal with high resolution but with low frequency (sub 500ps resolution with frequency of 1kHz). My idea was to configure the HRTIMA in one shot mode (non retriggerable) and to use the update event from TIM2 via TRGO to reset HRTIMA. As TIM2 is a 32bit timer I could reach the required frequency on keep all timers running synchronized. HRTIMA runs fine in one shot mode and by software reset it generates the signals one time. So fine so good. But it seems I cannot get TIM2 to reset / update the HR Timer. This is how I initialize the HRTimer:

// from cookbook

static
void
HRTIM_Minimal_Config(
void
)

{


/* Use the PLLx2 clock for HRTIM */

__HAL_RCC_HRTIM1_CONFIG(RCC_HRTIM1CLK_PLLCLK);


/* Enable HRTIM clock*/

__HRTIM1_CLK_ENABLE();


/* DLL calibration: periodic calibration enabled, period set to 14µs */

HRTIM1->sCommonRegs.DLLCR = HRTIM_CALIBRATIONRATE_14| HRTIM_DLLCR_CALEN;


/* Check DLL end of calibration flag */

while
(HRTIM1->sCommonRegs.ISR & HRTIM_IT_DLLRDY == RESET);


}


void
setupHRTimer(
void
)

{

// enbale TimerA in one shot non retriggerable mode with preload enable

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].TIMxCR = HRTIM_TIMCR_PREEN;


// reset on external event channel 2, source 3 -> TIM2_TRGO

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].RSTxR = HRTIM_RSTR_EXTEVNT2; 

HRTIM1->sCommonRegs.EECR1 = HRTIM_EECR1_EE2SRC_1;



// set period and compare registers

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].PERxR = 0x0F00;


HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP1xR = 0x0001; 

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP2xR = 0x0100; 


HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP1xR = 0x0200; 

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP2xR = 0x0400;


// set set and reset conditions

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].SETx1R = HRTIM_SET1R_CMP1;

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].RSTx1R = HRTIM_RST1R_CMP2;


HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].SETx2R = HRTIM_SET1R_CMP3;

HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].RSTx2R = HRTIM_RST1R_CMP4;


/* Enable TA1 and TA2 outputs */

HRTIM1->sCommonRegs.OENR = HRTIM_OENR_TA1OEN + HRTIM_OENR_TA2OEN; 


// start master timer and timer A

HRTIM1->sMasterRegs.MCR |= HRTIM_MCR_TACEN + HRTIM_MCR_MCEN

}

And here for TIM2:

void
setupTIM2(
void
)

{

__TIM2_CLK_ENABLE();


TIM2->CR2 |= TIM_CR2_MMS_1; 
// use update as TRGO

TIM2->ARR = 72000-1; 
// with 72MHz results on overflow every 1kHz

TIM2->PSC = 1; 

TIM15->CR1 |= TIM_CR1_CEN;

TIM15->EGR |= TIM_EGR_UG; 
// force update

}

I'm relatively new to ARMs and in special to STM32 so I would appreciate any help 😉 Thanks #hrtim #stm32f334 #nucleo #f334 #hr-timer #hrtim

[Amel NASRI]

Posted on January 28, 2015 at 12:09

Hi,

Refering to RM0364, only TIM1 can be used for HRTIM synchronization configuring SYNCIN bits with value ''

10: the on-chip TIM1 general purpose timer (TIM1 TRGO output)).

You can have a look to 

http://www.st.com/web/catalog/tools/FM147/CL1794/SC961/SS1743/LN1897/PF260613

 package where you will find various examples & use cases for the HRTIM (under STM32Cube_FW_F3_V1.1.0\Projects\STM32F3348-Discovery\Examples\HRTIM).-Mayla-

[tobias239955_stm1]

Posted on February 02, 2015 at 09:18

Hi Mayla,

Thank you very much for the information. Where in RM0364 can I find the information? Thank you very much,Tobias

[tobias239955_stm1]

Posted on February 02, 2015 at 10:10

Interesting. After solving some issues with my toolchain I now got it running as I wanted with TIM2:

1.
// reset on external event channel 2, source 3 -> TIM2_TRGO
2.
HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].RSTxR = HRTIM_RSTR_EXTEVNT2;
3.
HRTIM1->sCommonRegs.EECR1 = HRTIM_EECR1_EE2SRC_1;