mbed library sources: Modified to operate FRDM-KL25Z at 48MHz from internal 32kHz oscillator (nothing else changed).
Fork of mbed-src by
The only file that changed is: mbed-src-FLL48/targets/cmsis/TARGET_Freescale/TARGET_KL25Z/system_MKL25Z4.h
Diff: vendor/Freescale/KL25Z/cmsis/system_MKL25Z4.c
- Revision:
- 10:3bc89ef62ce7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/vendor/Freescale/KL25Z/cmsis/system_MKL25Z4.c Fri Jun 14 17:49:17 2013 +0100 @@ -0,0 +1,263 @@ +/* +** ################################################################### +** 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 <stdint.h> +#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))); +}