/* ** ################################################################### ** Processor: MKL25Z128VLK4 ** Compilers: ARM Compiler ** Freescale C/C++ for Embedded ARM ** GNU C Compiler ** IAR ANSI C/C++ Compiler for ARM ** ** Reference manual: KL25RM, Rev.1, Jun 2012 ** Version: rev. 1.1, 2012-06-21 ** ** Abstract: ** Provides a system configuration function and a global variable that ** contains the system frequency. It configures the device and initializes ** the oscillator (PLL) that is part of the microcontroller device. ** ** Copyright: 2012 Freescale Semiconductor, Inc. All Rights Reserved. ** ** http: www.freescale.com ** mail: support@freescale.com ** ** Revisions: ** - rev. 1.0 (2012-06-13) ** Initial version. ** - rev. 1.1 (2012-06-21) ** Update according to reference manual rev. 1. ** ** ################################################################### */ /** * @file MKL25Z4 * @version 1.1 * @date 2012-06-21 * @brief Device specific configuration file for MKL25Z4 (implementation file) * * Provides a system configuration function and a global variable that contains * the system frequency. It configures the device and initializes the oscillator * (PLL) that is part of the microcontroller device. */ #include #include "MKL25Z4.h" #define DISABLE_WDOG 1 #define CLOCK_SETUP 1 /* Predefined clock setups 0 ... Multipurpose Clock Generator (MCG) in FLL Engaged Internal (FEI) mode Reference clock source for MCG module is the slow internal clock source 32.768kHz Core clock = 41.94MHz, BusClock = 13.98MHz 1 ... Multipurpose Clock Generator (MCG) in PLL Engaged External (PEE) mode Reference clock source for MCG module is an external crystal 8MHz Core clock = 48MHz, BusClock = 24MHz 2 ... Multipurpose Clock Generator (MCG) in Bypassed Low Power External (BLPE) mode Core clock/Bus clock derived directly from an external crystal 8MHz with no multiplication Core clock = 8MHz, BusClock = 8MHz */ /*---------------------------------------------------------------------------- Define clock source values *----------------------------------------------------------------------------*/ #if (CLOCK_SETUP == 0) #define CPU_XTAL_CLK_HZ 8000000u /* Value of the external crystal or oscillator clock frequency in Hz */ #define CPU_INT_SLOW_CLK_HZ 32768u /* Value of the slow internal oscillator clock frequency in Hz */ #define CPU_INT_FAST_CLK_HZ 4000000u /* Value of the fast internal oscillator clock frequency in Hz */ #define DEFAULT_SYSTEM_CLOCK 41943040u /* Default System clock value */ #elif (CLOCK_SETUP == 1) #define CPU_XTAL_CLK_HZ 8000000u /* Value of the external crystal or oscillator clock frequency in Hz */ #define CPU_INT_SLOW_CLK_HZ 32768u /* Value of the slow internal oscillator clock frequency in Hz */ #define CPU_INT_FAST_CLK_HZ 4000000u /* Value of the fast internal oscillator clock frequency in Hz */ #define DEFAULT_SYSTEM_CLOCK 48000000u /* Default System clock value */ #elif (CLOCK_SETUP == 2) #define CPU_XTAL_CLK_HZ 8000000u /* Value of the external crystal or oscillator clock frequency in Hz */ #define CPU_INT_SLOW_CLK_HZ 32768u /* Value of the slow internal oscillator clock frequency in Hz */ #define CPU_INT_FAST_CLK_HZ 4000000u /* Value of the fast internal oscillator clock frequency in Hz */ #define DEFAULT_SYSTEM_CLOCK 8000000u /* Default System clock value */ #endif /* (CLOCK_SETUP == 2) */ /* ---------------------------------------------------------------------------- -- Core clock ---------------------------------------------------------------------------- */ uint32_t SystemCoreClock = DEFAULT_SYSTEM_CLOCK; /* ---------------------------------------------------------------------------- -- SystemInit() ---------------------------------------------------------------------------- */ void SystemInit (void) { #if (DISABLE_WDOG) /* Disable the WDOG module */ /* SIM_COPC: COPT=0,COPCLKS=0,COPW=0 */ SIM->COPC = (uint32_t)0x00u; #endif /* (DISABLE_WDOG) */ #if (CLOCK_SETUP == 0) /* SIM->CLKDIV1: OUTDIV1=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,OUTDIV4=2,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0 */ SIM->CLKDIV1 = (uint32_t)0x00020000UL; /* Update system prescalers */ /* Switch to FEI Mode */ /* MCG->C1: CLKS=0,FRDIV=0,IREFS=1,IRCLKEN=1,IREFSTEN=0 */ MCG->C1 = (uint8_t)0x06U; /* MCG_C2: LOCRE0=0,??=0,RANGE0=0,HGO0=0,EREFS0=0,LP=0,IRCS=0 */ MCG->C2 = (uint8_t)0x00U; /* MCG->C4: DMX32=0,DRST_DRS=1 */ MCG->C4 = (uint8_t)((MCG->C4 & (uint8_t)~(uint8_t)0xC0U) | (uint8_t)0x20U); /* OSC0->CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=0,SC4P=0,SC8P=0,SC16P=0 */ OSC0->CR = (uint8_t)0x80U; /* MCG->C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=0 */ MCG->C5 = (uint8_t)0x00U; /* MCG->C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=0 */ MCG->C6 = (uint8_t)0x00U; while((MCG->S & MCG_S_IREFST_MASK) == 0x00U) { /* Check that the source of the FLL reference clock is the internal reference clock. */ } while((MCG->S & 0x0CU) != 0x00U) { /* Wait until output of the FLL is selected */ } #elif (CLOCK_SETUP == 1) /* SIM->SCGC5: PORTA=1 */ SIM->SCGC5 |= (uint32_t)0x0200UL; /* Enable clock gate for ports to enable pin routing */ /* SIM->CLKDIV1: OUTDIV1=1,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,OUTDIV4=1,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0 */ SIM->CLKDIV1 = (uint32_t)0x10010000UL; /* Update system prescalers */ /* PORTA->PCR18: ISF=0,MUX=0 */ PORTA->PCR[18] &= (uint32_t)~0x01000700UL; /* PORTA->PCR19: ISF=0,MUX=0 */ PORTA->PCR[19] &= (uint32_t)~0x01000700UL; /* Switch to FBE Mode */ /* OSC0->CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=1,SC4P=0,SC8P=0,SC16P=1 */ OSC0->CR = (uint8_t)0x89U; /* MCG->C2: LOCRE0=0,??=0,RANGE0=2,HGO0=0,EREFS0=1,LP=0,IRCS=0 */ MCG->C2 = (uint8_t)0x24U; /* MCG->C1: CLKS=2,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0 */ MCG->C1 = (uint8_t)0x9AU; /* MCG->C4: DMX32=0,DRST_DRS=0 */ MCG->C4 &= (uint8_t)~(uint8_t)0xE0U; /* MCG->C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=1 */ MCG->C5 = (uint8_t)0x01U; /* MCG->C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=0 */ MCG->C6 = (uint8_t)0x00U; while((MCG->S & MCG_S_IREFST_MASK) != 0x00U) { /* Check that the source of the FLL reference clock is the external reference clock. */ } while((MCG->S & 0x0CU) != 0x08U) { /* Wait until external reference clock is selected as MCG output */ } /* Switch to PBE Mode */ /* MCG->C6: LOLIE0=0,PLLS=1,CME0=0,VDIV0=0 */ MCG->C6 = (uint8_t)0x40U; while((MCG->S & 0x0CU) != 0x08U) { /* Wait until external reference clock is selected as MCG output */ } while((MCG->S & MCG_S_LOCK0_MASK) == 0x00U) { /* Wait until locked */ } /* Switch to PEE Mode */ /* MCG->C1: CLKS=0,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0 */ MCG->C1 = (uint8_t)0x1AU; while((MCG->S & 0x0CU) != 0x0CU) { /* Wait until output of the PLL is selected */ } #elif (CLOCK_SETUP == 2) /* SIM->SCGC5: PORTA=1 */ SIM->SCGC5 |= (uint32_t)0x0200UL; /* Enable clock gate for ports to enable pin routing */ /* SIM->CLKDIV1: OUTDIV1=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,OUTDIV4=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0 */ SIM->CLKDIV1 = (uint32_t)0x00000000UL; /* Update system prescalers */ /* PORTA->PCR18: ISF=0,MUX=0 */ PORTA->PCR[18] &= (uint32_t)~0x01000700UL; /* PORTA->PCR19: ISF=0,MUX=0 */ PORTA->PCR[19] &= (uint32_t)~0x01000700UL; /* Switch to FBE Mode */ /* OSC0->CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=1,SC4P=0,SC8P=0,SC16P=1 */ OSC0->CR = (uint8_t)0x89U; /* MCG->C2: LOCRE0=0,??=0,RANGE0=2,HGO0=0,EREFS0=1,LP=0,IRCS=0 */ MCG->C2 = (uint8_t)0x24U; /* MCG->C1: CLKS=2,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0 */ MCG->C1 = (uint8_t)0x9AU; /* MCG->C4: DMX32=0,DRST_DRS=0 */ MCG->C4 &= (uint8_t)~(uint8_t)0xE0U; /* MCG->C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=0 */ MCG->C5 = (uint8_t)0x00U; /* MCG->C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=0 */ MCG->C6 = (uint8_t)0x00U; while((MCG->S & MCG_S_IREFST_MASK) != 0x00U) { /* Check that the source of the FLL reference clock is the external reference clock. */ } while((MCG->S & 0x0CU) != 0x08U) { /* Wait until external reference clock is selected as MCG output */ } /* Switch to BLPE Mode */ /* MCG->C2: LOCRE0=0,??=0,RANGE0=2,HGO0=0,EREFS0=1,LP=1,IRCS=0 */ MCG->C2 = (uint8_t)0x26U; while((MCG->S & 0x0CU) != 0x08U) { /* Wait until external reference clock is selected as MCG output */ } #endif /* (CLOCK_SETUP == 2) */ } /* ---------------------------------------------------------------------------- -- SystemCoreClockUpdate() ---------------------------------------------------------------------------- */ void SystemCoreClockUpdate (void) { uint32_t MCGOUTClock; /* Variable to store output clock frequency of the MCG module */ uint8_t Divider; if ((MCG->C1 & MCG_C1_CLKS_MASK) == 0x0u) { /* Output of FLL or PLL is selected */ if ((MCG->C6 & MCG_C6_PLLS_MASK) == 0x0u) { /* FLL is selected */ if ((MCG->C1 & MCG_C1_IREFS_MASK) == 0x0u) { /* External reference clock is selected */ MCGOUTClock = CPU_XTAL_CLK_HZ; /* System oscillator drives MCG clock */ Divider = (uint8_t)(1u << ((MCG->C1 & MCG_C1_FRDIV_MASK) >> MCG_C1_FRDIV_SHIFT)); MCGOUTClock = (MCGOUTClock / Divider); /* Calculate the divided FLL reference clock */ if ((MCG->C2 & MCG_C2_RANGE0_MASK) != 0x0u) { MCGOUTClock /= 32u; /* If high range is enabled, additional 32 divider is active */ } /* ((MCG->C2 & MCG_C2_RANGE0_MASK) != 0x0u) */ } else { /* (!((MCG->C1 & MCG_C1_IREFS_MASK) == 0x0u)) */ MCGOUTClock = CPU_INT_SLOW_CLK_HZ; /* The slow internal reference clock is selected */ } /* (!((MCG->C1 & MCG_C1_IREFS_MASK) == 0x0u)) */ /* Select correct multiplier to calculate the MCG output clock */ switch (MCG->C4 & (MCG_C4_DMX32_MASK | MCG_C4_DRST_DRS_MASK)) { case 0x0u: MCGOUTClock *= 640u; break; case 0x20u: MCGOUTClock *= 1280u; break; case 0x40u: MCGOUTClock *= 1920u; break; case 0x60u: MCGOUTClock *= 2560u; break; case 0x80u: MCGOUTClock *= 732u; break; case 0xA0u: MCGOUTClock *= 1464u; break; case 0xC0u: MCGOUTClock *= 2197u; break; case 0xE0u: MCGOUTClock *= 2929u; break; default: break; } } else { /* (!((MCG->C6 & MCG_C6_PLLS_MASK) == 0x0u)) */ /* PLL is selected */ Divider = (1u + (MCG->C5 & MCG_C5_PRDIV0_MASK)); MCGOUTClock = (uint32_t)(CPU_XTAL_CLK_HZ / Divider); /* Calculate the PLL reference clock */ Divider = ((MCG->C6 & MCG_C6_VDIV0_MASK) + 24u); MCGOUTClock *= Divider; /* Calculate the MCG output clock */ } /* (!((MCG->C6 & MCG_C6_PLLS_MASK) == 0x0u)) */ } else if ((MCG->C1 & MCG_C1_CLKS_MASK) == 0x40u) { /* Internal reference clock is selected */ if ((MCG->C2 & MCG_C2_IRCS_MASK) == 0x0u) { MCGOUTClock = CPU_INT_SLOW_CLK_HZ; /* Slow internal reference clock selected */ } else { /* (!((MCG->C2 & MCG_C2_IRCS_MASK) == 0x0u)) */ MCGOUTClock = CPU_INT_FAST_CLK_HZ / (1 << ((MCG->SC & MCG_SC_FCRDIV_MASK) >> MCG_SC_FCRDIV_SHIFT)); /* Fast internal reference clock selected */ } /* (!((MCG->C2 & MCG_C2_IRCS_MASK) == 0x0u)) */ } else if ((MCG->C1 & MCG_C1_CLKS_MASK) == 0x80u) { /* External reference clock is selected */ MCGOUTClock = CPU_XTAL_CLK_HZ; /* System oscillator drives MCG clock */ } else { /* (!((MCG->C1 & MCG_C1_CLKS_MASK) == 0x80u)) */ /* Reserved value */ return; } /* (!((MCG->C1 & MCG_C1_CLKS_MASK) == 0x80u)) */ SystemCoreClock = (MCGOUTClock / (1u + ((SIM->CLKDIV1 & SIM_CLKDIV1_OUTDIV1_MASK) >> SIM_CLKDIV1_OUTDIV1_SHIFT))); }