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targets/cmsis/TARGET_NUVOTON/TARGET_NUC472/StdDriver/nuc472_timer.c
- Committer:
- <>
- Date:
- 2016-09-02
- Revision:
- 144:ef7eb2e8f9f7
File content as of revision 144:ef7eb2e8f9f7:
/**************************************************************************//** * @file timer.c * @version V1.00 * $Revision: 6 $ * $Date: 14/05/29 1:13p $ * @brief NUC472/NUC442 TIMER driver source file * * @note * Copyright (C) 2013 Nuvoton Technology Corp. All rights reserved. *****************************************************************************/ #include "NUC472_442.h" /** @addtogroup NUC472_442_Device_Driver NUC472/NUC442 Device Driver @{ */ /** @addtogroup NUC472_442_TIMER_Driver TIMER Driver @{ */ /** @addtogroup NUC472_442_TIMER_EXPORTED_FUNCTIONS TIMER Exported Functions @{ */ /** * @brief 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. * @param[in] timer The base address of Timer module * @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 * @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 >= 0x4000000) { u32Prescale = 7; // real prescaler value is 8 u32Clk >>= 3; } else if(u32Clk >= 0x2000000) { u32Prescale = 3; // real prescaler value is 4 u32Clk >>= 2; } else if(u32Clk >= 0x1000000) { 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 This API stops Timer counting and disable the Timer interrupt function * @param[in] timer The base address of Timer module * @return None */ void TIMER_Close(TIMER_T *timer) { timer->CTL = 0; timer->EXTCTL = 0; } /** * @brief This API is used to create a delay loop for u32usec micro seconds * @param[in] timer The base address of Timer module * @param[in] u32Usec Delay period in micro seconds with 10 usec every step. Valid values are between 10~1000000 (10 micro second ~ 1 second) * @return None * @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; double fCmpr; // Clear current timer configuration timer->CTL = 0; timer->EXTCTL = 0; if(u32Clk == 10000) { // min delay is 100us if timer clock source is LIRC 10k u32Usec = ((u32Usec + 99) / 100) * 100; } else { // 10 usec every step u32Usec = ((u32Usec + 9) / 10) * 10; } if(u32Clk >= 0x4000000) { u32Prescale = 7; // real prescaler value is 8 u32Clk >>= 3; } else if(u32Clk >= 0x2000000) { u32Prescale = 3; // real prescaler value is 4 u32Clk >>= 2; } else if(u32Clk >= 0x1000000) { u32Prescale = 1; // real prescaler value is 2 u32Clk >>= 1; } // u32Usec * u32Clk might overflow if using uint32_t fCmpr = ((double)u32Usec * (double)u32Clk) / 1000000.0; timer->CMP = (uint32_t)fCmpr; timer->CTL = TIMER_CTL_CNTEN_Msk | u32Prescale; // one shot mode // 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 This API is used to enable timer capture function with specified mode and capture edge * @param[in] timer The base address of Timer module * @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 edge. Possible values are * - \ref TIMER_CAPTURE_FALLING_EDGE * - \ref TIMER_CAPTURE_RISING_EDGE * - \ref TIMER_CAPTURE_FALLING_THEN_RISING_EDGE * - \ref TIMER_CAPTURE_RISING_THEN_FALLING_EDGE * @return None * @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 This API is used to disable the Timer capture function * @param[in] timer The base address of Timer module * @return None */ void TIMER_DisableCapture(TIMER_T *timer) { timer->EXTCTL &= ~TIMER_EXTCTL_CAPEN_Msk; } /** * @brief This function is used to enable the Timer counter function with specify detection edge * @param[in] timer The base address of Timer module * @param[in] u32Edge Detection edge of counter pin. Could be ether * - \ref TIMER_COUNTER_RISING_EDGE, or * - \ref TIMER_COUNTER_FALLING_EDGE * @return None * @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 This API is used to disable the Timer event counter function. * @param[in] timer The base address of Timer module * @return None */ void TIMER_DisableEventCounter(TIMER_T *timer) { timer->CTL &= ~TIMER_CTL_EXTCNTEN_Msk; } /** * @brief This API is used to get the clock frequency of Timer * @param[in] timer The base address of Timer module * @return Timer clock frequency * @note This API cannot return correct clock rate if timer source is 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) { if(CLK->CLKSEL0 & CLK_CLKSEL0_PCLKSEL_Msk) return(SystemCoreClock / 2); else return(SystemCoreClock); } return(au32Clk[u32Src]); } /*@}*/ /* end of group NUC472_442_TIMER_EXPORTED_FUNCTIONS */ /*@}*/ /* end of group NUC472_442_TIMER_Driver */ /*@}*/ /* end of group NUC472_442_Device_Driver */ /*** (C) COPYRIGHT 2013 Nuvoton Technology Corp. ***/