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targets/TARGET_NUVOTON/TARGET_M451/device/StdDriver/m451_timer.c
- Committer:
- <>
- Date:
- 2016-10-28
- Revision:
- 149:156823d33999
File content as of revision 149:156823d33999:
/**************************************************************************//** * @file timer.c * @version V3.00 * $Revision: 6 $ * $Date: 15/08/11 10:26a $ * @brief M451 series Timer driver source file * * @note * Copyright (C) 2013~2015 Nuvoton Technology Corp. All rights reserved. *****************************************************************************/ #include "M451Series.h" /** @addtogroup Standard_Driver Standard Driver @{ */ /** @addtogroup TIMER_Driver TIMER Driver @{ */ /** @addtogroup TIMER_EXPORTED_FUNCTIONS TIMER Exported Functions @{ */ /** * @brief Open Timer with Operate Mode and Frequency * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * @param[in] u32Mode Operation mode. Possible options are * - \ref TIMER_ONESHOT_MODE * - \ref TIMER_PERIODIC_MODE * - \ref TIMER_TOGGLE_MODE * - \ref TIMER_CONTINUOUS_MODE * @param[in] u32Freq Target working frequency * * @return Real timer working frequency * * @details This API is used to configure timer to operate in specified mode and frequency. * If timer cannot work in target frequency, a closest frequency will be chose and returned. * @note After calling this API, Timer is \b NOT running yet. But could start timer running be calling * \ref TIMER_Start macro or program registers directly. */ uint32_t TIMER_Open(TIMER_T *timer, uint32_t u32Mode, uint32_t u32Freq) { uint32_t u32Clk = TIMER_GetModuleClock(timer); uint32_t u32Cmpr = 0, u32Prescale = 0; // Fastest possible timer working freq is (u32Clk / 2). While cmpr = 2, pre-scale = 0. if(u32Freq > (u32Clk / 2)) { u32Cmpr = 2; } else { if(u32Clk > 64000000) { u32Prescale = 7; // real prescaler value is 8 u32Clk >>= 3; } else if(u32Clk > 32000000) { u32Prescale = 3; // real prescaler value is 4 u32Clk >>= 2; } else if(u32Clk > 16000000) { u32Prescale = 1; // real prescaler value is 2 u32Clk >>= 1; } u32Cmpr = u32Clk / u32Freq; } timer->CTL = u32Mode | u32Prescale; timer->CMP = u32Cmpr; return(u32Clk / (u32Cmpr * (u32Prescale + 1))); } /** * @brief Stop Timer Counting * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * * @return None * * @details This API stops timer counting and disable all timer interrupt function. */ void TIMER_Close(TIMER_T *timer) { timer->CTL = 0; timer->EXTCTL = 0; } /** * @brief Create a specify Delay Time * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * @param[in] u32Usec Delay period in micro seconds. Valid values are between 100~1000000 (100 micro second ~ 1 second). * * @return None * * @details This API is used to create a delay loop for u32usec micro seconds by using timer one-shot mode. * @note This API overwrites the register setting of the timer used to count the delay time. * @note This API use polling mode. So there is no need to enable interrupt for the timer module used to generate delay. */ void TIMER_Delay(TIMER_T *timer, uint32_t u32Usec) { uint32_t u32Clk = TIMER_GetModuleClock(timer); uint32_t u32Prescale = 0, delay = (SystemCoreClock / u32Clk) + 1; uint32_t u32Cmpr, u32NsecPerTick; // Clear current timer configuration/ timer->CTL = 0; timer->EXTCTL = 0; if(u32Clk <= 1000000) // min delay is 1000 us if timer clock source is <= 1 MHz { if(u32Usec < 1000) u32Usec = 1000; if(u32Usec > 1000000) u32Usec = 1000000; } else { if(u32Usec < 100) u32Usec = 100; if(u32Usec > 1000000) u32Usec = 1000000; } if(u32Clk <= 1000000) { u32Prescale = 0; u32NsecPerTick = 1000000000 / u32Clk; u32Cmpr = (u32Usec * 1000) / u32NsecPerTick; } else { if(u32Clk > 64000000) { u32Prescale = 7; // real prescaler value is 8 u32Clk >>= 3; } else if(u32Clk > 32000000) { u32Prescale = 3; // real prescaler value is 4 u32Clk >>= 2; } else if(u32Clk > 16000000) { u32Prescale = 1; // real prescaler value is 2 u32Clk >>= 1; } if(u32Usec < 250) { u32Cmpr = (u32Usec * u32Clk) / 1000000; } else { u32NsecPerTick = 1000000000 / u32Clk; u32Cmpr = (u32Usec * 1000) / u32NsecPerTick; } } timer->CMP = u32Cmpr; timer->CTL = TIMER_CTL_CNTEN_Msk | TIMER_ONESHOT_MODE | u32Prescale; // When system clock is faster than timer clock, it is possible timer active bit cannot set in time while we check it. // And the while loop below return immediately, so put a tiny delay here allowing timer start counting and raise active flag. for(; delay > 0; delay--) { __NOP(); } while(timer->CTL & TIMER_CTL_ACTSTS_Msk); } /** * @brief Enable Timer Capture Function * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * @param[in] u32CapMode Timer capture mode. Could be * - \ref TIMER_CAPTURE_FREE_COUNTING_MODE * - \ref TIMER_CAPTURE_COUNTER_RESET_MODE * @param[in] u32Edge Timer capture trigger edge. Possible values are * - \ref TIMER_CAPTURE_FALLING_EDGE * - \ref TIMER_CAPTURE_RISING_EDGE * - \ref TIMER_CAPTURE_FALLING_AND_RISING_EDGE * * @return None * * @details This API is used to enable timer capture function with specify capture trigger edge \n * to get current counter value or reset counter value to 0. * @note Timer frequency should be configured separately by using \ref TIMER_Open API, or program registers directly. */ void TIMER_EnableCapture(TIMER_T *timer, uint32_t u32CapMode, uint32_t u32Edge) { timer->EXTCTL = (timer->EXTCTL & ~(TIMER_EXTCTL_CAPFUNCS_Msk | TIMER_EXTCTL_CAPEDGE_Msk)) | u32CapMode | u32Edge | TIMER_EXTCTL_CAPEN_Msk; } /** * @brief Disable Timer Capture Function * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * * @return None * * @details This API is used to disable the timer capture function. */ void TIMER_DisableCapture(TIMER_T *timer) { timer->EXTCTL &= ~TIMER_EXTCTL_CAPEN_Msk; } /** * @brief Enable Timer Counter Function * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * @param[in] u32Edge Detection edge of counter pin. Could be ether * - \ref TIMER_COUNTER_FALLING_EDGE, or * - \ref TIMER_COUNTER_RISING_EDGE * * @return None * * @details This function is used to enable the timer counter function with specify detection edge. * @note Timer compare value should be configured separately by using \ref TIMER_SET_CMP_VALUE macro or program registers directly. * @note While using event counter function, \ref TIMER_TOGGLE_MODE cannot set as timer operation mode. */ void TIMER_EnableEventCounter(TIMER_T *timer, uint32_t u32Edge) { timer->EXTCTL = (timer->EXTCTL & ~TIMER_EXTCTL_CNTPHASE_Msk) | u32Edge; timer->CTL |= TIMER_CTL_EXTCNTEN_Msk; } /** * @brief Disable Timer Counter Function * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * * @return None * * @details This API is used to disable the timer event counter function. */ void TIMER_DisableEventCounter(TIMER_T *timer) { timer->CTL &= ~TIMER_CTL_EXTCNTEN_Msk; } /** * @brief Get Timer Clock Frequency * * @param[in] timer The pointer of the specified Timer module. It could be TIMER0, TIMER1, TIMER2, TIMER3. * * @return Timer clock frequency * * @details This API is used to get the timer clock frequency. * @note This API cannot return correct clock rate if timer source is from external clock input. */ uint32_t TIMER_GetModuleClock(TIMER_T *timer) { uint32_t u32Src; const uint32_t au32Clk[] = {__HXT, __LXT, 0, 0, 0, __LIRC, 0, __HIRC}; if(timer == TIMER0) u32Src = (CLK->CLKSEL1 & CLK_CLKSEL1_TMR0SEL_Msk) >> CLK_CLKSEL1_TMR0SEL_Pos; else if(timer == TIMER1) u32Src = (CLK->CLKSEL1 & CLK_CLKSEL1_TMR1SEL_Msk) >> CLK_CLKSEL1_TMR1SEL_Pos; else if(timer == TIMER2) u32Src = (CLK->CLKSEL1 & CLK_CLKSEL1_TMR2SEL_Msk) >> CLK_CLKSEL1_TMR2SEL_Pos; else // Timer 3 u32Src = (CLK->CLKSEL1 & CLK_CLKSEL1_TMR3SEL_Msk) >> CLK_CLKSEL1_TMR3SEL_Pos; if(u32Src == 2) { return (SystemCoreClock); } return (au32Clk[u32Src]); } /*@}*/ /* end of group TIMER_EXPORTED_FUNCTIONS */ /*@}*/ /* end of group TIMER_Driver */ /*@}*/ /* end of group Standard_Driver */ /*** (C) COPYRIGHT 2013~2015 Nuvoton Technology Corp. ***/