Beispiel #1
0
/*lint -esym(765,Cpu_Interrupt) Disable MISRA rule (8.10) checking for symbols (Cpu_Interrupt). */
void __init_hardware(void)
{

  /*** !!! Here you can place your own code before PE initialization using property "User code before PE initialization" on the build options tab. !!! ***/

  /*** ### MKL25Z128VLK4 "Cpu" init code ... ***/
  /*** PE initialization code after reset ***/
  SCB_VTOR = (uint32_t)(&__vect_table); /* Set the interrupt vector table position */
  /* Disable the WDOG module */
  /* SIM_COPC: ??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,COPT=0,COPCLKS=0,COPW=0 */
  SIM_COPC = SIM_COPC_COPT(0x00);

  /* System clock initialization */
  /* SIM_CLKDIV1: OUTDIV1=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,OUTDIV4=3,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0 */
  SIM_CLKDIV1 = (SIM_CLKDIV1_OUTDIV1(0x00) | SIM_CLKDIV1_OUTDIV4(0x03)); /* Set the system prescalers to safe value */
  /* SIM_SCGC5: PORTD=1,PORTB=1,PORTA=1 */
  SIM_SCGC5 |= SIM_SCGC5_PORTD_MASK |
               SIM_SCGC5_PORTB_MASK |
               SIM_SCGC5_PORTA_MASK;   /* Enable clock gate for ports to enable pin routing */
  if ((PMC_REGSC & PMC_REGSC_ACKISO_MASK) != 0x0U) {
    /* PMC_REGSC: ACKISO=1 */
    PMC_REGSC |= PMC_REGSC_ACKISO_MASK; /* Release IO pads after wakeup from VLLS mode. */
  }
  /* 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 = (SIM_CLKDIV1_OUTDIV1(0x00) | SIM_CLKDIV1_OUTDIV4(0x00)); /* Update system prescalers */
  /* SIM_SOPT2: PLLFLLSEL=0 */
  SIM_SOPT2 &= (uint32_t)~(uint32_t)(SIM_SOPT2_PLLFLLSEL_MASK); /* Select FLL as a clock source for various peripherals */
  /* SIM_SOPT1: OSC32KSEL=3 */
  SIM_SOPT1 |= SIM_SOPT1_OSC32KSEL(0x03); /* LPO 1kHz oscillator drives 32 kHz clock for various peripherals */
  /* SIM_SOPT2: TPMSRC=1 */
  SIM_SOPT2 = (uint32_t)((SIM_SOPT2 & (uint32_t)~(uint32_t)(
               SIM_SOPT2_TPMSRC(0x02)
              )) | (uint32_t)(
               SIM_SOPT2_TPMSRC(0x01)
              ));                      /* Set the TPM clock */
  /* Switch to FEI Mode */
  /* MCG_C1: CLKS=0,FRDIV=0,IREFS=1,IRCLKEN=1,IREFSTEN=0 */
  MCG_C1 = MCG_C1_CLKS(0x00) |
           MCG_C1_FRDIV(0x00) |
           MCG_C1_IREFS_MASK |
           MCG_C1_IRCLKEN_MASK;
  /* MCG_C2: LOCRE0=0,??=0,RANGE0=0,HGO0=0,EREFS0=0,LP=0,IRCS=0 */
  MCG_C2 = MCG_C2_RANGE0(0x00);
  /* MCG_C4: DMX32=0,DRST_DRS=0 */
  MCG_C4 &= (uint8_t)~(uint8_t)((MCG_C4_DMX32_MASK | MCG_C4_DRST_DRS(0x03)));
  /* OSC0_CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=0,SC4P=0,SC8P=0,SC16P=0 */
  OSC0_CR = OSC_CR_ERCLKEN_MASK;
  /* MCG_C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=0 */
  MCG_C5 = MCG_C5_PRDIV0(0x00);
  /* MCG_C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=0 */
  MCG_C6 = MCG_C6_VDIV0(0x00);
  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 */
  }
  /*** End of PE initialization code after reset ***/

  /*** !!! Here you can place your own code after PE initialization using property "User code after PE initialization" on the build options tab. !!! ***/

}
Beispiel #2
0
/*****************************************************************************
 * @name     pll_init
 *
 * @brief:   Initialization of the MCU.
 *
 * @param  : None
 *
 * @return : None
 *****************************************************************************
 * It will configure the MCU to disable STOP and COP Modules.
 * It also set the MCG configuration and bus clock frequency.
 ****************************************************************************/
static unsigned char pll_init()
{
	/* First move to FBE mode */
	/* Enable external oscillator, RANGE=1, HGO=1, EREFS=1, LP=0, IRCS=0 */
	MCG_C2 = MCG_C2_RANGE0(2) | MCG_C2_HGO0_MASK | MCG_C2_EREFS0_MASK | MCG_C2_IRCS_MASK;
	
    /* Select external oscillator and Reference Divider and clear IREFS to start ext osc
	   CLKS=2, FRDIV=3, IREFS=0, IRCLKEN=0, IREFSTEN=0 */
    MCG_C1 = MCG_C1_CLKS(2) | MCG_C1_FRDIV(3);

	/* Wait for oscillator to initialize */
   while (!(MCG_S & MCG_S_OSCINIT0_MASK)){};

   	/* Wait for Reference clock Status bit to clear */
    while (MCG_S & MCG_S_IREFST_MASK){};

    /* Wait for clock status bits to show clock source is ext ref clk */
    while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x2){};

    MCG_C5 = MCG_C5_PRDIV0(BSP_REF_CLOCK_DIV - 1) | MCG_C5_PLLCLKEN0_MASK;

    /* Ensure MCG_C6 is at the reset default of 0. LOLIE disabled,
     PLL enabled, clk monitor disabled, PLL VCO divider is clear */
    MCG_C6 = 0;

    /* Set system options dividers */
	#if (defined MCU_MK20D5) || (defined MCU_MK40D7)
		SIM_CLKDIV1 =   SIM_CLKDIV1_OUTDIV1(BSP_CORE_DIV - 1) | 	/* core/system clock */
						SIM_CLKDIV1_OUTDIV2(BSP_BUS_DIV - 1)  | 	/* peripheral clock; */
						SIM_CLKDIV1_OUTDIV4(BSP_FLASH_DIV - 1);     /* flash clock */
	#else  
		SIM_CLKDIV1 =   SIM_CLKDIV1_OUTDIV1(BSP_CORE_DIV - 1) 	| 	/* Core/system clock */
						SIM_CLKDIV1_OUTDIV2(BSP_BUS_DIV - 1)  	| 	/* Peripheral clock; */
						SIM_CLKDIV1_OUTDIV3(BSP_FLEXBUS_DIV - 1)|  	/* FlexBus clock driven to the external pin (FB_CLK)*/
						SIM_CLKDIV1_OUTDIV4(BSP_FLASH_DIV - 1);     /* Flash clock */
	#endif
		
    /* Set the VCO divider and enable the PLL, LOLIE = 0, PLLS = 1, CME = 0, VDIV = */
    MCG_C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV0(BSP_CLOCK_MUL - 24); /* 2MHz * BSP_CLOCK_MUL */

    while (!(MCG_S & MCG_S_PLLST_MASK)){}; 	/* Wait for PLL status bit to set */
    while (!(MCG_S & MCG_S_LOCK0_MASK)){}; 	/* Wait for LOCK bit to set */

    /* Transition into PEE by setting CLKS to 0
    CLKS=0, FRDIV=3, IREFS=0, IRCLKEN=0, IREFSTEN=0 */
    MCG_C1 &= ~MCG_C1_CLKS_MASK;

    /* Wait for clock status bits to update */
    while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x3){};
     
    /* Enable the ER clock of oscillators */
    OSC_CR = OSC_CR_ERCLKEN_MASK | OSC_CR_EREFSTEN_MASK;
    
    /* Now running in PEE Mode */
    SIM_SOPT1 |= SIM_SOPT1_USBREGEN_MASK;
    
    return 0;
} //pll_init
Beispiel #3
0
/*-------------------------------------------------------------------------------*/
void FBE(void)
	{
	
		MCG->C6 &= ~MCG_C6_CME0_MASK; 					//External clock monitor is disabled for OSC0.

    MCG->C2 |= MCG_C2_RANGE0(3) |						// Very high frequency range selected for the crystal oscillator 
               MCG_C2_EREFS0_MASK  ; 				//Oscillator requested
		
    MCG->C4 &= ~MCG_C4_DRST_DRS_MASK;   // Reset DCO Range
    MCG->C4 &= ~MCG_C4_DMX32_MASK;			// DCO Maximum Frequency
    MCG->C4 |= MCG_C4_DRST_DRS(1);			// 31.25 * 1280 = 40000kHz
    
    MCG->C6 &= ~MCG_C6_PLLS_MASK;				// Select FLL
			
    MCG->C1 &= ~MCG_C1_CLKS_MASK;				// Reset Clock Source Select
    MCG->C1 |= MCG_C1_CLKS(2) | 				//External reference clock is selected
						 	MCG_C1_FRDIV(3)| 					// Divide Factor is 256
							MCG_C1_IRCLKEN_MASK;			//MCGIRCLK active
					// Output of FLL is selected for MCGOUTCLK
    
    while((MCG->S & MCG_S_OSCINIT0_MASK) == 0); 		// wait for osc init
    while((MCG->S & MCG_S_PLLST_MASK) != 0); 				// wait for FLL
    while((MCG->S & MCG_S_CLKST_MASK) != MCG_S_CLKST(2)); // wait for EXTAL is selected
		 SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(1 - 1) |  				// core/system clock = MCGOUTCLK / 1 = 8 / 1 = 8MHz
     SIM_CLKDIV1_OUTDIV4(1 - 1);   // flash/bus clock = core/system / 1 = 8MHz
	
	}
Beispiel #4
0
/*!
 *  @brief      时钟分频设置函数
 *  @param      outdiv1    内核分频系数,       core    clk = MCG / (outdiv1 +1)
 *  @param      outdiv2    bus分频系数,        bus     clk = MCG / (outdiv2 +1)
 *  @param      outdiv3    flexbus分频系数,    flexbus clk = MCG / (outdiv3 +1)
 *  @param      outdiv4    flash分频系数,      flash   clk = MCG / (outdiv4 +1)
 *  @since      v1.0
 *  @author     飞思卡尔公司
 *  Sample usage:       set_sys_dividers(0,1, 9,3);     // core clk = MCG ; bus clk = MCG / 2 ; flexbus clk = MCG /10 ; flash clk = MCG / 4;
 */
__RAMFUNC  void set_sys_dividers(uint32 outdiv1, uint32 outdiv2, uint32 outdiv3, uint32 outdiv4)
{
    /*
    * This routine must be placed in RAM. It is a workaround for errata e2448.
    * Flash prefetch must be disabled when the flash clock divider is changed.
    * This cannot be performed while executing out of flash.
    * There must be a short delay after the clock dividers are changed before prefetch
    * can be re-enabled.
    */
    uint32 temp_reg;
    uint8 i;

    temp_reg = FMC_PFAPR; // store present value of FMC_PFAPR

    // set M0PFD through M7PFD to 1 to disable prefetch
    FMC_PFAPR |= FMC_PFAPR_M7PFD_MASK | FMC_PFAPR_M6PFD_MASK | FMC_PFAPR_M5PFD_MASK
                 | FMC_PFAPR_M4PFD_MASK | FMC_PFAPR_M3PFD_MASK | FMC_PFAPR_M2PFD_MASK
                 | FMC_PFAPR_M1PFD_MASK | FMC_PFAPR_M0PFD_MASK;

    // set clock dividers to desired value
    SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(outdiv1) | SIM_CLKDIV1_OUTDIV2(outdiv2)
                  | SIM_CLKDIV1_OUTDIV3(outdiv3) | SIM_CLKDIV1_OUTDIV4(outdiv4);

    // wait for dividers to change
    for (i = 0 ; i < outdiv4 ; i++)
        {}

    FMC_PFAPR = temp_reg; // re-store original value of FMC_PFAPR

    return;
} // set_sys_dividers
static void SetSIMRegisters()
{
  // TODO
  SIM->COPC = SIM_COPC_COPT(0);//disable watchdog immediately

  //do the rest in order listed in data sheet

  SIM->SOPT2 = SIM_SOPT2_UART0SRC(0)|SIM_SOPT2_TPMSRC(0);//no clocks enabled  for
                                                        // uart0 or TPM counterClock

  SIM->SOPT4 = ((0 << SIM_SOPT4_TPM1CLKSEL_SHIFT)&SIM_SOPT4_TPM1CLKSEL_MASK)|((0 << SIM_SOPT4_TPM0CLKSEL_SHIFT)&SIM_SOPT4_TPM0CLKSEL_MASK)|((0<<SIM_SOPT4_TPM1CH0SRC_SHIFT)&SIM_SOPT4_TPM1CH0SRC_MASK);//don't care settings

  SIM->SOPT5 = ((0<<SIM_SOPT5_UART0ODE_SHIFT)&SIM_SOPT5_UART0ODE_MASK)|((0<<SIM_SOPT5_UART0RXSRC_SHIFT)&SIM_SOPT5_UART0RXSRC_MASK)|((0<<SIM_SOPT5_UART0TXSRC_SHIFT)&SIM_SOPT5_UART0TXSRC_MASK);//don't cares

  SIM->SOPT7 = ((0<<SIM_SOPT7_ADC0ALTTRGEN_SHIFT)&SIM_SOPT7_ADC0ALTTRGEN_MASK)|((0<<SIM_SOPT7_ADC0PRETRGSEL_SHIFT)&SIM_SOPT7_ADC0PRETRGSEL_MASK)|((0<<SIM_SOPT7_ADC0TRGSEL_SHIFT)&SIM_SOPT7_ADC0TRGSEL_MASK);//don't cares

  SIM->SCGC4 = ((1<<SIM_SCGC4_SPI0_SHIFT)&SIM_SCGC4_SPI0_MASK)|((0<<SIM_SCGC4_CMP_SHIFT)&SIM_SCGC4_CMP_MASK)|((0<<SIM_SCGC4_UART0_SHIFT)&SIM_SCGC4_UART0_MASK)|((1<<SIM_SCGC4_I2C1_SHIFT)&SIM_SCGC4_I2C1_MASK)|((1<<SIM_SCGC4_I2C0_SHIFT)&SIM_SCGC4_I2C0_MASK);//enable the I2C module

  SIM->SCGC5 = ((1<<SIM_SCGC5_PORTB_SHIFT)&SIM_SCGC5_PORTB_MASK)|((1<<SIM_SCGC5_PORTA_SHIFT)&SIM_SCGC5_PORTA_MASK)|((0<<SIM_SCGC5_LPTMR_SHIFT)&SIM_SCGC5_LPTMR_MASK);//enable both ports

  SIM->SCGC6 = ((0<<SIM_SCGC6_ADC0_SHIFT)&SIM_SCGC6_ADC0_MASK)|((0<<SIM_SCGC6_TPM1_SHIFT)&SIM_SCGC6_TPM1_MASK)|((0<<SIM_SCGC6_TPM0_SHIFT)&SIM_SCGC6_TPM0_MASK)|((0<<SIM_SCGC6_FTF_SHIFT)&SIM_SCGC6_FTF_MASK);//don't cares

  SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0)|SIM_CLKDIV1_OUTDIV4(4);//clk configured for 4MHz core, .8 MHz Bus Clk (fastest allowable in BLPI mode)

  //this is unchanged from default, do not alter. If we need to save power we can turn off flash, but this has caused hard faults. we need to move the interrupt vectors out of flash to do this SIM_FCFG1 = ((0<<SIM_FCFG1_FLASHDOZE_SHIFT)&SIM_FCFG1_FLASHDOZE_MASK)|((0<<SIM_FCFG1_FLASHDIS_SHIFT)&SIM_FCFG1_FLASHDIS_MASK);//flash disabled to conserve power, other settings are don't cares, TODO:verify flash size setting is unimportant

  //SIM_FCFG2 = SIM_FCFG2 only has maxaddr0, which is read only.

  //SIM_SRVCOP, we do not need to reset timer, it is  disabled already.

  return;
}
Beispiel #6
0
void __ramfunc__
kinesis_setdividers(uint32_t div1, uint32_t div2, uint32_t div3, uint32_t div4)
{
  uint32_t regval;
  int i;

  /* Save the current value of the Flash Access Protection Register */

  regval = getreg32(KINETIS_FMC_PFAPR);
  
  /* Set M0PFD through M7PFD to 1 to disable prefetch */

  putreg32(FMC_PFAPR_M7PFD | FMC_PFAPR_M6PFD | FMC_PFAPR_M5PFD |
           FMC_PFAPR_M4PFD | FMC_PFAPR_M3PFD | FMC_PFAPR_M2PFD |
           FMC_PFAPR_M1PFD | FMC_PFAPR_M0PFD,
           KINETIS_FMC_PFAPR);

  /* Set clock dividers to desired value */

  putreg32(SIM_CLKDIV1_OUTDIV1(div1) | SIM_CLKDIV1_OUTDIV2(div2) |
           SIM_CLKDIV1_OUTDIV3(div3) | SIM_CLKDIV1_OUTDIV4(div4),
           KINETIS_SIM_CLKDIV1);

  /* Wait for dividers to change */

  for (i = 0 ; i < div4 ; i++);
  
  /* Re-store the saved value of FMC_PFAPR */

  putreg32(regval, KINETIS_FMC_PFAPR);
}
Beispiel #7
0
void PEE(void)
{
	  MCG->C6 &= ~MCG_C6_CME0_MASK;

    MCG->C2 &= ~MCG_C2_LP_MASK;
    MCG->C2 |= MCG_C2_RANGE0(3) |// Very high frequency range selected for the crystal oscillator 
               MCG_C2_EREFS0_MASK ;

    MCG->C5 &= ~MCG_C5_PRDIV0_MASK;
    MCG->C5 |= MCG_C5_PRDIV0(2 - 1); // External clock div 4
    
    MCG->C6 &= ~MCG_C6_VDIV0_MASK;
    MCG->C6 |= MCG_C6_VDIV0(24 - 24) | // Mul 24. 8 / 4 * 24 = 48MHz
               MCG_C6_CME0_MASK |
               MCG_C6_PLLS_MASK;
		
		MCG->C1 &= ~MCG_C1_CLKS_MASK;
    MCG->C1 |= ~MCG_C1_CLKS_MASK | // Output of PLL is selected for MCGOUTCLK
								MCG_C1_FRDIV(3) |
								MCG_C1_IRCLKEN_MASK;
	
    while((MCG->S & MCG_S_OSCINIT0_MASK) == 0); // wait for osc init.
    while((MCG->S & MCG_S_PLLST_MASK) != MCG_S_PLLST_MASK); // wait for PLL
    while((MCG->S & MCG_S_CLKST_MASK) != MCG_S_CLKST(3)); // wait for PLL is selected
		
		SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(2 - 1) |  // core/system clock = MCGOUTCLK / 2 = 96 / 2 = 48MHz
									 SIM_CLKDIV1_OUTDIV4(2 - 1);   // flash/bus clock = core/system / 2 = 24MHz
}
Beispiel #8
0
Datei: cpu.c Projekt: JMR-b/RIOT
/**
 * @brief Configure the controllers clock system
 */
static void cpu_clock_init(void)
{
    /* setup system prescalers */
    SIM->CLKDIV1 = (uint32_t)SIM_CLKDIV1_OUTDIV4(1);

    modem_clock_init();
    kinetis_mcg_set_mode(KINETIS_MCG_PEE);
}
Beispiel #9
0
void InitClock()
{
// If the internal load capacitors are being used, they should be selected 
// before enabling the oscillator. Application specific. 16pF and 8pF selected
// in this example
  OSC_CR = OSC_CR_SC16P_MASK | OSC_CR_SC8P_MASK;
// Enabling the oscillator for 8 MHz crystal
// RANGE=1, should be set to match the frequency of the crystal being used
// HGO=1, high gain is selected, provides better noise immunity but does draw
// higher current
// EREFS=1, enable the external oscillator
// LP=0, low power mode not selected (not actually part of osc setup)
// IRCS=0, slow internal ref clock selected (not actually part of osc setup)
  MCG_C2 = MCG_C2_RANGE(1) | MCG_C2_HGO_MASK | MCG_C2_EREFS_MASK;
// Select ext oscillator, reference divider and clear IREFS to start ext osc
// CLKS=2, select the external clock source 
// FRDIV=3, set the FLL ref divider to keep the ref clock in range 
//         (even if FLL is not being used) 8 MHz / 256 = 31.25 kHz         
// IREFS=0, select the external clock 
// IRCLKEN=0, disable IRCLK (can enable it if desired)
// IREFSTEN=0, disable IRC in stop mode (can keep it enabled in stop if desired)
  MCG_C1 = MCG_C1_CLKS(2) | MCG_C1_FRDIV(3);
// wait for oscillator to initialize
  while (!(MCG_S & MCG_S_OSCINIT_MASK)){}  
// wait for Reference clock to switch to external reference 
  while (MCG_S & MCG_S_IREFST_MASK){} 
// Wait for MCGOUT to switch over to the external reference clock 
  while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x2){}
// Now configure the PLL and move to PBE mode
// set the PRDIV field to generate a 4MHz reference clock (8MHz /2)
  MCG_C5 = MCG_C5_PRDIV(1); // PRDIV=1 selects a divide by 2
// set the VDIV field to 0, which is x24, giving 4 x 24  = 96 MHz
// the PLLS bit is set to enable the PLL
// the clock monitor is enabled, CME=1 to cause a reset if crystal fails  
// LOLIE can be optionally set to enable the loss of lock interrupt
  
  MCG_C6 = MCG_C6_CME_MASK | MCG_C6_PLLS_MASK;
// wait until the source of the PLLS clock has switched to the PLL  
  while (!(MCG_S & MCG_S_PLLST_MASK)){}
// wait until the PLL has achieved lock
  while (!(MCG_S & MCG_S_LOCK_MASK)){}
// set up the SIM clock dividers BEFORE switching to the PLL to ensure the
// system clock speeds are in spec.
// core = PLL (96MHz), bus = PLL/2 (48MHz), flexbus = PLL/2 (48MHz), flash = PLL/4 (24MHz)  
  SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(1) 
              | SIM_CLKDIV1_OUTDIV3(1) | SIM_CLKDIV1_OUTDIV4(3);
  
// Transition into PEE by setting CLKS to 0
// previous MCG_C1 settings remain the same, just need to set CLKS to 0
  MCG_C1 &= ~MCG_C1_CLKS_MASK;
// Wait for MCGOUT to switch over to the PLL
  while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x3){}
// The USB clock divider in the System Clock Divider Register 2 (SIM_CLKDIV2) 
// should be configured to generate the 48 MHz USB clock before configuring 
// the USB module.
    SIM_CLKDIV2 |= SIM_CLKDIV2_USBDIV(1); // sets USB divider to /2 assuming reset
										// state of the SIM_CLKDIV2 register
}
/*FUNCTION**********************************************************************
 *
 * Function Name : CLOCK_HAL_SetOutDiv
 * Description   : Set all clock out dividers setting at the same time
 * This function will set the setting for all clock out dividers.
 *
 *END**************************************************************************/
void CLOCK_HAL_SetOutDiv(SIM_Type * base,
                         uint8_t outdiv1,
                         uint8_t outdiv2,
                         uint8_t outdiv3,
                         uint8_t outdiv4)
{
    SIM_WR_CLKDIV1(base, (SIM_RD_CLKDIV1(base) & ~(SIM_CLKDIV1_OUTDIV1_MASK | SIM_CLKDIV1_OUTDIV4_MASK)) \
                      | (SIM_CLKDIV1_OUTDIV1(outdiv1) | SIM_CLKDIV1_OUTDIV4(outdiv4)));
}
Beispiel #11
0
// Private functions
static void hw_mcg_init(void)
{
    /* Adjust clock dividers (core/system=div/1, bus=div/2, flex bus=div/2, flash=div/4) */
    SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(SYS_CLK_DIV-1) | SIM_CLKDIV1_OUTDIV2(BUS_CLK_DIV-1) | 
        SIM_CLKDIV1_OUTDIV3(BUS_CLK_DIV-1) | SIM_CLKDIV1_OUTDIV4(FLASH_CLK_DIV-1);
   
    /* Configure FEI internal clock speed */
    MCG->C4 = (SYS_CLK_DMX | SYS_CLK_DRS);
    while((MCG->C4 & (MCG_C4_DRST_DRS_MASK | MCG_C4_DMX32_MASK)) != (SYS_CLK_DMX | SYS_CLK_DRS));
}
//-----------------------------------------------------------------------------
// FUNCTION:    boot_init_clock
// SCOPE:       Bootloader application system function
// DESCRIPTION: Init the sytem clock. Here it uses PEE with external 8M crystal, Core clock = 48MHz, Bus clock = 24MHz
//-----------------------------------------------------------------------------
void Boot_Init_Clock()
{
    SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0x00) |
                  SIM_CLKDIV1_OUTDIV2(0x01) |
                  SIM_CLKDIV1_OUTDIV3(0x04) |
                  SIM_CLKDIV1_OUTDIV4(0x04); /* Set the system prescalers to safe value */
    SIM_SCGC5 |= (uint32_t)SIM_SCGC5_PORTA_MASK; /* Enable EXTAL/XTAL pins clock gate */
    PORTA_PCR18 &= (uint32_t)~(uint32_t)(
                PORT_PCR_ISF_MASK |
                PORT_PCR_MUX(0x07)
               );
    /* Is external crystal/resonator used in targeted clock configuration? */ /* If yes, initialize also XTAL pin routing */
    /* PORTA_PCR19: ISF=0,MUX=0 */
    PORTA_PCR19 &= (uint32_t)~(uint32_t)(
         PORT_PCR_ISF_MASK |
         PORT_PCR_MUX(0x07)
         );
    MCG_C2 = 0xa4;
    OSC_CR = 0x00; /* Set OSC_CR (OSCERCLK enable, oscillator capacitor load) */
    MCG_C7 = 0x00; /* Select MCG OSC clock source */
    MCG_C1 = 0x98; /* Set C1 (clock source selection, FLL ext. reference divider, int. reference enable etc.) */
    while((MCG_S & MCG_S_OSCINIT0_MASK) == 0x00U) { /* Check that the oscillator is running */
      }
    while((MCG_S & MCG_S_IREFST_MASK) != 0x00U) { /* Check that the source of the FLL reference clock is the external reference clock. */
    }
    MCG_C4 = 0x17; /* Set C4 (FLL output; trim values not changed) */
    MCG_C5 = 0x00; /* Set C5 (PLL settings, PLL reference divider etc.) */
    MCG_C6 = 0x00; /* Set C6 (PLL select, VCO divider etc.) */
    while((MCG_S & 0x0CU) != 0x08U) { /* Wait until external reference clock is selected as MCG output */
    }
    OSC_CR = 0x80; /* Set OSC_CR (OSCERCLK enable, oscillator capacitor load) */
    MCG_C7 = 0x00; /* Select MCG OSC clock source */
    MCG_C1 = 0x9a; /* Set C1 (clock source selection, FLL ext. reference divider, int. reference enable etc.) */
    MCG_C2 = 0x24; /* Set C2 (freq. range, ext. and int. reference selection etc.; trim values not changed) */
    MCG_C5 = 0x23; /* Set C5 (PLL settings, PLL reference divider etc.) */
    MCG_C6 = 0x40; /* Set C6 (PLL select, VCO divider etc.) */
    while((MCG_S & MCG_S_LOCK0_MASK) == 0x00U) { /* Wait until PLL is locked*/
    }
    while((MCG_S & 0x0CU) != 0x08U) { /* Wait until external reference clock is selected as MCG output */
    }
    OSC_CR = 0x80; /* Set OSC_CR (OSCERCLK enable, oscillator capacitor load) */
    MCG_C7 = 0x00; /* Select MCG OSC clock source */
    MCG_C1 = 0x1a;
    MCG_C5 = 0x23;
    MCG_C6 = 0x40;
    while((MCG_S & MCG_S_LOCK0_MASK) == 0x00U) { /* Wait until PLL is locked*/
    }
    while((MCG_S & 0x0CU) != 0x0CU) { /* Wait until output of the PLL is selected */
    }
    //while (NextMode != (TargetMode & CPU_MCG_MODE_INDEX_MASK)); /* Loop until the target MCG mode is set */
    //	SIM_CLKDIV1 = 0x11100000;
    //	SIM_SOPT1 = 0x800C9010;
    //	SIM_SOPT2 = 0x00011000;
}
Beispiel #13
0
void vfnMcuConfig (void)
{ 
#if defined(CLKOUT)
  SIM_SCGC5 |= SIM_SCGC5_PORTC_MASK;            //Enable clock on PTC3
  PORTC_PCR3 = PORT_PCR_MUX(0x05);              //PTC3 as CLKOUT
  SIM_SOPT2 &= ~SIM_SOPT2_CLKOUTSEL_MASK;       //Clear CLKOUTSEL register
  SIM_SOPT2 |= SIM_SOPT2_CLKOUTSEL(0x02);       //Select BUSCLK as CLKOUT output
#endif
  
  /* Actual PLL frequency is 48MHz --> 96MHz needed for USB to work due freq divider by 2 */
  
  /* Set dividers for new PLL frequency */
  SIM_CLKDIV1 = ( 0
                        | SIM_CLKDIV1_OUTDIV1(1)
                        | SIM_CLKDIV1_OUTDIV4(1) );
  
  /* Return MCG to PBE */
  MCG_C6 |= MCG_C6_PLLS_MASK;
  MCG_C2 &= ~MCG_C2_LP_MASK;
  MCG_C1 &= ~MCG_C1_IREFS_MASK;
  MCG_C1 |= MCG_C1_CLKS(2);
  
  /* Move MCG to FBE */
  MCG_C6 &= ~MCG_C6_PLLS_MASK;
  MCG_C5 &= ~MCG_C5_PLLCLKEN0_MASK;
  
  /* Configure PLL to run @96MHz */
  MCG_C6 &= ~MCG_C6_VDIV0_MASK;
  MCG_C5 &= ~MCG_C5_PRDIV0_MASK;
  MCG_C6 |= (USB_PLL_VDIV - 24);
  MCG_C5 |= (USB_PLL_PRDIV - 1);
  MCG_C5 |= MCG_C5_PLLCLKEN0_MASK;              //Enable PLL
  while(!(MCG_S & MCG_S_LOCK0_MASK));           //Wait for PLL to lock
  
  /* Go to PBE */
  MCG_C6 |= MCG_C6_PLLS_MASK;
  
  /* Go to PEE */
  MCG_C1 &= ~MCG_C1_CLKS_MASK;
  
  /* MCG is now configured */
  
  /* Reconfigure UART0 with new frequency */
  
#if TERM_PORT_NUM==0
  uart0_init (UART0_BASE_PTR, 48000, TERMINAL_BAUD);
#elif TERM_PORT_NUM==1
  uart_init (UART1_BASE_PTR, 24000, TERMINAL_BAUD);
#else
  uart_init (UART2_BASE_PTR, 24000, TERMINAL_BAUD);
#endif
   
}
Beispiel #14
0
void Clock_init(void)
{
// Init system clock
  /* System clock initialization */
  /* SIM_SCGC5: PORTA=1 */
  SIM_SCGC5 |= SIM_SCGC5_PORTA_MASK;   /* Enable clock gate for ports to enable pin routing */
  /* SIM_CLKDIV1: OUTDIV1=0,??=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 = (SIM_CLKDIV1_OUTDIV1(0x00) | SIM_CLKDIV1_OUTDIV4(0x01)); /* Update system prescalers */
  /* SIM_SOPT2: PLLFLLSEL=0 */
  SIM_SOPT2 &= (uint32_t)~(uint32_t)(SIM_SOPT2_PLLFLLSEL_MASK); /* Select FLL as a clock source for various peripherals */
  /* SIM_SOPT1: OSC32KSEL=0 */
  SIM_SOPT1 &= (uint32_t)~(uint32_t)(SIM_SOPT1_OSC32KSEL(0x03)); /* System oscillator drives 32 kHz clock for various peripherals */
  /* SIM_SOPT2: TPMSRC=1 */
  SIM_SOPT2 = (uint32_t)((SIM_SOPT2 & (uint32_t)~(uint32_t)(
			   SIM_SOPT2_TPMSRC(0x02)
			  )) | (uint32_t)(
			   SIM_SOPT2_TPMSRC(0x01)
			  ));                      /* Set the TPM clock */
  /* PORTA_PCR18: ISF=0,MUX=0 */
  PORTA_PCR18 &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));
  /* PORTA_PCR19: ISF=0,MUX=0 */
  PORTA_PCR19 &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));
  /* MCG_SC: FCRDIV=1 */
  MCG_SC = (uint8_t)((MCG_SC & (uint8_t)~(uint8_t)(
			MCG_SC_FCRDIV(0x06)
		   )) | (uint8_t)(
			MCG_SC_FCRDIV(0x01)
		   ));
  /* Switch to FEE Mode */
  /* MCG_C2: LOCRE0=0,??=0,RANGE0=2,HGO0=0,EREFS0=1,LP=0,IRCS=1 */
  MCG_C2 = (MCG_C2_RANGE0(0x02) | MCG_C2_EREFS0_MASK | MCG_C2_IRCS_MASK);
  /* OSC0_CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=0,SC4P=0,SC8P=0,SC16P=0 */
  OSC0_CR = OSC_CR_ERCLKEN_MASK;
  /* MCG_C1: CLKS=0,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0 */
  MCG_C1 = (MCG_C1_CLKS(0x00) | MCG_C1_FRDIV(0x03) | MCG_C1_IRCLKEN_MASK);
  /* MCG_C4: DMX32=0,DRST_DRS=1 */
  MCG_C4 = (uint8_t)((MCG_C4 & (uint8_t)~(uint8_t)(
			MCG_C4_DMX32_MASK |
			MCG_C4_DRST_DRS(0x02)
		   )) | (uint8_t)(
			MCG_C4_DRST_DRS(0x01)
		   ));
  /* MCG_C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=0 */
  MCG_C5 = MCG_C5_PRDIV0(0x00);
  /* MCG_C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=0 */
  MCG_C6 = MCG_C6_VDIV0(0x00);
  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) != 0x00U) {    /* Wait until output of the FLL is selected */
  }
  /*** End of PE initialization code after reset ***/

}
Beispiel #15
0
void PBE_to_PEE(void)
{
	MCG->C5 |= MCG_C5_PLLCLKEN0_MASK  ;				// MCGPLLCLK is active
	SIM->SOPT2 |=SIM_SOPT2_PLLFLLSEL_MASK; 		// Selects the MCGPLLCLK clock for various peripheral clocking options
	MCG->C1 &=~MCG_C1_CLKS_MASK;  					 	// PLL or FLL reference clock is selected.
	
	SIM->CLKDIV1 |=SIM_CLKDIV1_OUTDIV1(0x1);  //Factor Divider1 == 2 => core clock = 96MHz/2 =48MHz 
	SIM->CLKDIV1 |=SIM_CLKDIV1_OUTDIV4(0x1); 	//Factor Divider4 == 2 => bus clock  = 48MHz/2 =24MHz 
	
	while((MCG->S & 0x0CU) != 0x0CU) {     		/* Wait until output of the PLL is selected */
  }

}
/*FUNCTION**********************************************************************
 *
 * Function Name : CLOCK_HAL_SetOutDiv
 * Description   : Set all clock out dividers setting at the same time
 * This function will set the setting for all clock out dividers.
 *
 *END**************************************************************************/
void CLOCK_HAL_SetOutDiv(SIM_Type * base,
                         uint8_t outdiv1,
                         uint8_t outdiv2,
                         uint8_t outdiv3,
                         uint8_t outdiv4)
{
    uint32_t clkdiv1 = 0;

    clkdiv1 |= SIM_CLKDIV1_OUTDIV1(outdiv1);
    clkdiv1 |= SIM_CLKDIV1_OUTDIV4(outdiv4);

    SIM_WR_CLKDIV1(base, clkdiv1);
}
/**
 **===========================================================================
 **  Reset handler
 **===========================================================================
 */
void __init_hardware(void) {
	/* This is a cleaned up output of Processor Expert generated code */

	/* Set the interrupt vector table position */
	SCB_VTOR = (uint32_t)__vector_table;
#if 0
	/* Disable the WDOG module */
	SIM_COPC = SIM_COPC_COPT(0x00);                                   
#endif
	/* System clock initialization */
	/* Enable clock gate for ports to enable pin routing */
	SIM_SCGC5 |= SIM_SCGC5_PORTA_MASK;
	/* Update system prescalers */
	SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0x00) | SIM_CLKDIV1_OUTDIV4(0x01);
	/* Select FLL as a clock source for various peripherals */
	SIM_SOPT2 &= ~SIM_SOPT2_PLLFLLSEL_MASK;
	/* LPO 1kHz oscillator drives 32 kHz clock for various peripherals */
	SIM_SOPT1 |= SIM_SOPT1_OSC32KSEL(0x03);
	/* Set the TPM clock */
	SIM_SOPT2 &= ~SIM_SOPT2_TPMSRC(0x01);
	SIM_SOPT2 |= SIM_SOPT2_TPMSRC(0x02);
	/* Enable XTAL IO pins */
	PORTA_PCR18 = PORT_PCR_MUX(0);
	PORTA_PCR19 = PORT_PCR_MUX(0);

	/* Switch to FBE Mode */
	MCG_C2 = MCG_C2_RANGE0(0x02) | MCG_C2_EREFS0_MASK;
	OSC0_CR = OSC_CR_ERCLKEN_MASK;
	MCG_C1 = MCG_C1_CLKS(0x02) | MCG_C1_FRDIV(0x03) | MCG_C1_IRCLKEN_MASK;
	MCG_C4 &= ~MCG_C4_DMX32_MASK | MCG_C4_DRST_DRS(0x03);
	MCG_C5 = MCG_C5_PRDIV0(0x03);
	MCG_C6 = MCG_C6_VDIV0(0x00);
	
	/* Check that the source of the FLL reference clock is the external reference clock. */
	while((MCG_S & MCG_S_IREFST_MASK) != 0x00U);
	/* Wait until external reference clock is selected as MCG output */
	while((MCG_S & 0x0CU) != 0x08U);

	/* Switch to PBE Mode */
	MCG_C6 = (MCG_C6_PLLS_MASK | MCG_C6_VDIV0(0x00));
	/* Wait until external reference clock is selected as MCG output */
	while((MCG_S & 0x0CU) != 0x08U);
	/* Wait until locked */
	while((MCG_S & MCG_S_LOCK0_MASK) == 0x00U);

	/* Switch to PEE Mode */
	MCG_C1 = MCG_C1_CLKS(0x00) | MCG_C1_FRDIV(0x03) | MCG_C1_IRCLKEN_MASK;
	/* Wait until output of the PLL is selected */
	while((MCG_S & 0x0CU) != 0x0CU);
}
Beispiel #18
0
static void hw_mcg_init(void)
{
#ifdef FREESCALE_KSDK_BM
    BOARD_BootClockHSRUN();
#else
    /* Adjust clock dividers (core/system=div/1, bus=div/2, flex bus=div/2, flash=div/4) */
    SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(SYS_CLK_DIV-1) | SIM_CLKDIV1_OUTDIV2(BUS_CLK_DIV-1) | 
        SIM_CLKDIV1_OUTDIV3(BUS_CLK_DIV-1) | SIM_CLKDIV1_OUTDIV4(FLASH_CLK_DIV-1);
   
    /* Configure FEI internal clock speed */
    MCG->C4 = (SYS_CLK_DMX | SYS_CLK_DRS);
    while((MCG->C4 & (MCG_C4_DRST_DRS_MASK | MCG_C4_DMX32_MASK)) != (SYS_CLK_DMX | SYS_CLK_DRS));
#endif
}
Beispiel #19
0
/** PLL initialization.
 */
static void pll_init(void) {
    // First move to FBE mode
    // Enable external oscillator, RANGE=0, HGO=, EREFS=, LP=, IRCS=
    MCG_C2 = 0;
    
    // Select external oscilator and Reference Divider and clear IREFS to start ext osc
    // CLKS=2, FRDIV=3, IREFS=0, IRCLKEN=0, IREFSTEN=0
    MCG_C1 = MCG_C1_CLKS(2) | MCG_C1_FRDIV(3);
    
    while (MCG_S & MCG_S_IREFST_MASK); // wait for Reference clock Status bit to clear
    
    while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x2); // Wait for clock status bits to show clock source is ext ref clk
    
    // ... FBE mode
    // Configure PLL Ref Divider, PLLCLKEN=0, PLLSTEN=0, PRDIV=0x18
    // The crystal frequency is used to select the PRDIV value. Only even frequency crystals are supported
    // that will produce a 2MHz reference clock to the PLL.
    MCG_C5 = MCG_C5_PRDIV(REF_CLOCK_DIV - 1);

    // Ensure MCG_C6 is at the reset default of 0. LOLIE disabled, PLL disabled, clk monitor disabled, PLL VCO divider is clear
    MCG_C6 = 0;

    // Set system options dividers
    SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(CORE_DIV - 1) |           // core/system clock
                  SIM_CLKDIV1_OUTDIV2(BUS_DIV - 1) |            // peripheral clock
                  SIM_CLKDIV1_OUTDIV3(FLEXBUS_DIV - 1) |        // FlexBus clock driven to the external pin (FB_CLK).
                  SIM_CLKDIV1_OUTDIV4(FLASH_DIV - 1);           // flash clock
    
    // Set the VCO divider and enable the PLL, LOLIE = 0, PLLS = 1, CME = 0, VDIV =
    MCG_C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV(PLL_CLOCK_MUL - 24);    // 2MHz * BSP_CLOCK_MUL

    while (!(MCG_S & MCG_S_PLLST_MASK));        // wait for PLL status bit to set
    while (!(MCG_S & MCG_S_LOCK_MASK));         // Wait for LOCK bit to set

    // ...running PBE mode

    // Transition into PEE by setting CLKS to 0
    // CLKS=0, FRDIV=3, IREFS=0, IRCLKEN=0, IREFSTEN=0
    MCG_C1 &= ~MCG_C1_CLKS_MASK;

    // Wait for clock status bits to update
    while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x3);

    // ...running PEE mode  
}
Beispiel #20
0
static inline void set_safe_clock_dividers(void)
{
    /*
     * We want to achieve the following clocks:
     * Core/system: <100MHz
     * Bus: <50MHz
     * FlexBus: <50MHz
     * Flash: <25MHz
     *
     * using dividers 1-2-2-4 will obey the above limits when using a 96MHz FLL source.
     */
    SIM->CLKDIV1 = (
                       SIM_CLKDIV1_OUTDIV1(CONFIG_CLOCK_K60_SYS_DIV) | /* Core/System clock divider */
                       SIM_CLKDIV1_OUTDIV2(CONFIG_CLOCK_K60_BUS_DIV) | /* Bus clock divider */
                       SIM_CLKDIV1_OUTDIV3(CONFIG_CLOCK_K60_FB_DIV) | /* FlexBus divider, not used in Mulle */
                       SIM_CLKDIV1_OUTDIV4(CONFIG_CLOCK_K60_FLASH_DIV)); /* Flash clock divider */

}
Beispiel #21
0
Datei: cpu.c Projekt: iplon/RIOT
/**
 * @brief Configure the controllers clock system
 */
static void cpu_clock_init(void)
{
    /* setup system prescalers */
    SIM->CLKDIV1 = (uint32_t)SIM_CLKDIV1_OUTDIV4(1);

    modem_clock_init();
    kinetis_mcg_set_mode(KINETIS_MCG_PEE);

    /*
     * Setup USBFSOTG clock
     * USB clock should be 48 MHz, use MCGPLLCLK as clock source
     * usb_clk = (pll_clk * 1 / 1) = 48MHz * 1 / 1 = 48MHz
     */
#if MODULE_USBDEV
    SIM->SOPT2 &= ~(SIM_SOPT2_USBSRC_MASK | SIM_SOPT2_PLLFLLSEL_MASK);
    SIM->SOPT2 |= SIM_SOPT2_USBSRC_MASK | SIM_SOPT2_PLLFLLSEL_MASK;
    SIM->CLKDIV2 = 0;
#endif
}
Beispiel #22
0
void FEI(void)
	{
		 MCG->C1 |= MCG_C1_IREFS_MASK; 							// Internal clock (32.768kHz) for FLL

    MCG->C4 &= ~MCG_C4_DRST_DRS_MASK;
    MCG->C4 |= MCG_C4_DRST_DRS(1);							// 32.768 * 732 = 24MHz
		
    MCG->C2 |= MCG_C2_RANGE0(0) ;								// Reset MCG_C2
               			
		
    MCG->C1 &= ~MCG_C1_CLKS_MASK;								// Output of FLL is selected for MCGOUTCLK
		MCG->C1 |=	 MCG_C1_CLKS(0) | 
							 	 MCG_C1_FRDIV(0)| 							// 	Divide Factor is 32
								 MCG_C1_IRCLKEN_MASK;						//	MCGIRCLK active
		
    while((MCG->S & MCG_S_IREFST_MASK) == 0); 	// wait for Internal clock is selected
    while((MCG->S & MCG_S_CLKST_MASK) != 0); 		// wait for FLL is selected
		SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(1 - 1) |  // core/system clock = MCGOUTCLK / 1 = 8 / 1 = 24MHz
    SIM_CLKDIV1_OUTDIV4(1 - 1);   // flash/bus clock = core/system / 1 = 24MHz
		SIM->SCGC5    |= (1UL << 11);        		/* Enable Clock to Port C */ 
	}
Beispiel #23
0
// =============================================================================
// 功能:系统时钟初始化,从系统上电使用FEI到切换到使用外部的50M时钟合为时钟源,并经过
//       PLL分频和倍频,使内核时钟为120M,bus时钟为2分频,FlexBus3分频,Flash6分频,
//       各个模块(如portA~E)的时钟各自使用时配置,此处只配置系统时钟
// 参数:无
// 返回:无
// =============================================================================
void SysClockInit(void)
{
    //初始化端口时钟,在系统初始化时全部打开
    SIM->SCGC5 |= (SIM_SCGC5_PORTA_MASK
                  | SIM_SCGC5_PORTB_MASK
                  | SIM_SCGC5_PORTC_MASK
                  | SIM_SCGC5_PORTD_MASK
                  | SIM_SCGC5_PORTE_MASK
                  | SIM_SCGC5_PORTF_MASK );

    //初始化PLL前,先初始化系统时钟分步器,分别用于配置
    //core/system时钟、bus时钟、FlexBus时钟、Flash时钟
    SIM->CLKDIV1 = ( 0
                    | SIM_CLKDIV1_OUTDIV1(0)
                    | SIM_CLKDIV1_OUTDIV2(1)
                    | SIM_CLKDIV1_OUTDIV3(2)
                    | SIM_CLKDIV1_OUTDIV4(5) );

    //系统的PLL时钟分频配置,用于生成MCGOUTCLK = 120M
    //对于50M的crystal,分频为5,PLL倍频为24,则主时钟计算公式为:
    //MCGOUTCLK = ((50M/5) * 24)/2 = 120M
    PLL_Init(CLK0_FREQ_HZ,PLL0_PRDIV,PLL0_VDIV);
}
/*
 * LPLD_Set_SYS_DIV
 * 设置系统始终分频
 *
 * 说明:
 * 这段代码必须放置在RAM中,目的是防止程序跑飞,详见官方文档errata e2448.
 * 当Flash时钟分频改变的时候,Flash预读取必须禁用.
 * 禁止从Flash中运行以下代码.
 * 在预读取被重新使能之前必须在时钟分频改变后有一段小的延时.
 *
 * 参数:
 *    outdiv1~outdiv4--分别为core, bus, FlexBus, Flash时钟分频系数
 */
__ramfunc void LPLD_Set_SYS_DIV(uint32 outdiv1, uint32 outdiv2, uint32 outdiv3, uint32 outdiv4)
{
  uint32 temp_reg;
  uint8 i;
  
  temp_reg = FMC->PFAPR; // 备份 FMC_PFAPR 寄存器
  
  // 设置 M0PFD 到 M7PFD 为 1 禁用预先读取
  FMC->PFAPR |= FMC_PFAPR_M7PFD_MASK | FMC_PFAPR_M6PFD_MASK | FMC_PFAPR_M5PFD_MASK
             | FMC_PFAPR_M4PFD_MASK | FMC_PFAPR_M3PFD_MASK | FMC_PFAPR_M2PFD_MASK
             | FMC_PFAPR_M1PFD_MASK | FMC_PFAPR_M0PFD_MASK;
  
  // 设置时钟分频为期望值  
  SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(outdiv1) | SIM_CLKDIV1_OUTDIV2(outdiv2) 
              | SIM_CLKDIV1_OUTDIV3(outdiv3) | SIM_CLKDIV1_OUTDIV4(outdiv4);

  // 延时一小段时间等待改变
  for (i = 0 ; i < outdiv4 ; i++)
  {}
  
  FMC->PFAPR = temp_reg; // 回复原先的 FMC_PFAPR 寄存器值
  
  return;
} // set_sys_dividers
Beispiel #25
0
/*lint -esym(765,Cpu_Interrupt) Disable MISRA rule (8.10) checking for symbols (Cpu_Interrupt). */
void __init_hardware(void)
{

  /*** !!! Here you can place your own code before PE initialization using property "User code before PE initialization" on the build options tab. !!! ***/

  /*** ### MKL46Z256VMC4 "Cpu" init code ... ***/
  /*** PE initialization code after reset ***/
  SCB_VTOR = (uint32_t)(&__vect_table); /* Set the interrupt vector table position */
  /* Disable the WDOG module */
  /* SIM_COPC: ??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,COPT=0,COPCLKS=0,COPW=0 */
  SIM_COPC = SIM_COPC_COPT(0x00);                                   
  /* System clock initialization */
  /* SIM_SCGC5: PORTE=1,PORTC=1,PORTB=1,PORTA=1 */
  SIM_SCGC5 |= SIM_SCGC5_PORTE_MASK |
               SIM_SCGC5_PORTC_MASK |
               SIM_SCGC5_PORTB_MASK |
               SIM_SCGC5_PORTA_MASK;   /* Enable clock gate for ports to enable pin routing */
  /* SIM_CLKDIV1: OUTDIV1=0,??=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 = (SIM_CLKDIV1_OUTDIV1(0x00) | SIM_CLKDIV1_OUTDIV4(0x01)); /* Update system prescalers */
  /* SIM_SOPT2: PLLFLLSEL=1 */
  SIM_SOPT2 |= SIM_SOPT2_PLLFLLSEL_MASK; /* Select PLL as a clock source for various peripherals */
  /* SIM_SOPT1: OSC32KSEL=2 */
  SIM_SOPT1 = (uint32_t)((SIM_SOPT1 & (uint32_t)~(uint32_t)(
               SIM_SOPT1_OSC32KSEL(0x01)
              )) | (uint32_t)(
               SIM_SOPT1_OSC32KSEL(0x02)
              ));                      /* System oscillator drives 32 kHz clock for various peripherals */
  /* SIM_SOPT2: TPMSRC=1 */
  SIM_SOPT2 = (uint32_t)((SIM_SOPT2 & (uint32_t)~(uint32_t)(
               SIM_SOPT2_TPMSRC(0x02)
              )) | (uint32_t)(
               SIM_SOPT2_TPMSRC(0x01)
              ));                      /* Set the TPM clock */
  /* PORTA_PCR18: ISF=0,MUX=0 */
  PORTA_PCR18 &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));                                   
  /* PORTA_PCR19: ISF=0,MUX=0 */
  PORTA_PCR19 &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));                                   
  /* Switch to FBE Mode */
  /* MCG_C2: LOCRE0=0,RANGE0=2,HGO0=0,EREFS0=1,LP=0,IRCS=0 */
  MCG_C2 = (uint8_t)((MCG_C2 & (uint8_t)~(uint8_t)(
            MCG_C2_LOCRE0_MASK |
            MCG_C2_RANGE0(0x01) |
            MCG_C2_HGO0_MASK |
            MCG_C2_LP_MASK |
            MCG_C2_IRCS_MASK
           )) | (uint8_t)(
            MCG_C2_RANGE0(0x02) |
            MCG_C2_EREFS0_MASK
           ));                                  
  /* OSC0_CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=0,SC4P=0,SC8P=0,SC16P=0 */
  OSC0_CR = OSC_CR_ERCLKEN_MASK;                                   
  /* MCG_C1: CLKS=2,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0 */
  MCG_C1 = (MCG_C1_CLKS(0x02) | MCG_C1_FRDIV(0x03) | MCG_C1_IRCLKEN_MASK);                                   
  /* MCG_C4: DMX32=0,DRST_DRS=0 */
  MCG_C4 &= (uint8_t)~(uint8_t)((MCG_C4_DMX32_MASK | MCG_C4_DRST_DRS(0x03)));                                   
  /* MCG_C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=3 */
  MCG_C5 = MCG_C5_PRDIV0(0x03);                                   
  /* MCG_C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=0 */
  MCG_C6 = MCG_C6_VDIV0(0x00);                                   
  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 = (MCG_C6_PLLS_MASK | MCG_C6_VDIV0(0x00));                                   
  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 = (MCG_C1_CLKS(0x00) | MCG_C1_FRDIV(0x03) | MCG_C1_IRCLKEN_MASK);                                   
  while((MCG_S & 0x0CU) != 0x0CU) {    /* Wait until output of the PLL is selected */
  }
  /* Initialization of the RTC_CLKIN pin */
  /* PORTC_PCR1: ISF=0,MUX=1 */
  PORTC_PCR1 = (uint32_t)((PORTC_PCR1 & (uint32_t)~(uint32_t)(
                PORT_PCR_ISF_MASK |
                PORT_PCR_MUX(0x06)
               )) | (uint32_t)(
                PORT_PCR_MUX(0x01)
               ));                                  
  /*** End of PE initialization code after reset ***/

  /*** !!! Here you can place your own code after PE initialization using property "User code after PE initialization" on the build options tab. !!! ***/

}
/*! Sets up the clock out of RESET
 *!
 */
void clock_initialise(void) {

#if (CLOCK_MODE == CLOCK_MODE_RESET)
   // No clock setup
#else
   // XTAL/EXTAL Pins
   SIM_SCGC5  |= SIM_SCGC5_PORTA_MASK;
   PORTA_PCR3  = PORT_PCR_MUX(0);
   PORTA_PCR4  = PORT_PCR_MUX(0);

   // Configure the Crystal Oscillator
   OSC0_CR = OSC_CR_ERCLKEN_M|OSC_CR_EREFSTEN_M|OSC_CR_SCP_M;

   // Fast Internal Clock divider
   MCG_SC = MCG_SC_FCRDIV_M;

   // Out of reset MCG is in FEI mode
   // =============================================================

   SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(3) | SIM_CLKDIV1_OUTDIV2(7) | SIM_CLKDIV1_OUTDIV3(3) | SIM_CLKDIV1_OUTDIV4(7);

   // Switch from FEI -> FEI/FBI/FEE/FBE
   // =============================================================

   // Set up crystal or external clock source
   MCG_C2 =
            MCG_C2_LOCRE0_M     | // LOCRE0 = 0,1   -> Loss of clock reset
            MCG_C2_RANGE0_M     | // RANGE0 = 0,1,2 -> Oscillator low/high/very high clock range
            MCG_C2_HGO0_M       | // HGO0   = 0,1   -> Oscillator low power/high gain
            MCG_C2_EREFS0_M     | // EREFS0 = 0,1   -> Select external clock/crystal oscillator
            MCG_C2_IRCS_M;        // IRCS   = 0,1   -> Select slow/fast internal clock for internal reference

#if ((CLOCK_MODE == CLOCK_MODE_FEI) || (CLOCK_MODE == CLOCK_MODE_FBI) || (CLOCK_MODE == CLOCK_MODE_BLPI) )
   // Transition via FBI
   //=====================================
#define BYPASS (1) // CLKS value used while FLL locks
   MCG_C1 =  MCG_C1_CLKS(BYPASS)     | // CLKS     = 2     -> External reference source while PLL locks
             MCG_C1_FRDIV_M          | // FRDIV    = N     -> XTAL/2^n ~ 31.25 kHz
             MCG_C1_IREFS_M          | // IREFS    = 0,1   -> External/Slow IRC for FLL source
             MCG_C1_IRCLKEN_M        | // IRCLKEN  = 0,1   -> IRCLK disable/enable
             MCG_C1_IREFSTEN_M;        // IREFSTEN = 0,1   -> Internal reference enabled in STOP mode

   // Wait for S_IREFST to indicate FLL Reference has switched
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_IREFST_MASK) != (MCG_C1_IREFS_V<<MCG_S_IREFST_SHIFT));

   // Wait for S_CLKST to indicating that OUTCLK has switched to bypass PLL/FLL
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(BYPASS));

   // Set FLL Parameters
   MCG_C4 = (MCG_C4&~(MCG_C4_DMX32_MASK|MCG_C4_DRST_DRS_MASK))|MCG_C4_DMX32_M|MCG_C4_DRST_DRS_M;
#endif

#if ((CLOCK_MODE == CLOCK_MODE_FBE) || (CLOCK_MODE == CLOCK_MODE_FEE) || (CLOCK_MODE == CLOCK_MODE_PLBE) || (CLOCK_MODE == CLOCK_MODE_PBE) || (CLOCK_MODE == CLOCK_MODE_PEE))

   // Transition via FBE
   //=====================================
#define BYPASS (2) // CLKS value used while PLL locks
   MCG_C1 =  MCG_C1_CLKS(BYPASS)     | // CLKS     = 2     -> External reference source while PLL locks
             MCG_C1_FRDIV_M          | // FRDIV    = N     -> XTAL/2^n ~ 31.25 kHz
             MCG_C1_IREFS_M          | // IREFS    = 0,1   -> External/Slow IRC for FLL source
             MCG_C1_IRCLKEN_M        | // IRCLKEN  = 0,1   -> IRCLK disable/enable
             MCG_C1_IREFSTEN_M;        // IREFSTEN = 0,1   -> Internal reference enabled in STOP mode

#if (MCG_C2_EREFS_V != 0)
   // Wait for oscillator stable (if used)
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_OSCINIT0_MASK) == 0);
#endif

   // Wait for S_IREFST to indicate FLL Reference has switched
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_IREFST_MASK) != (MCG_C1_IREFS_V<<MCG_S_IREFST_SHIFT));

   // Wait for S_CLKST to indicating that OUTCLK has switched to bypass PLL/FLL
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(BYPASS));

   // Set FLL Parameters
   MCG_C4 = (MCG_C4&~(MCG_C4_DMX32_MASK|MCG_C4_DRST_DRS_MASK))|MCG_C4_DMX32_M|MCG_C4_DRST_DRS_M;
#endif

   // Select FEI/FBI/FEE/FBE clock mode
   MCG_C1 =  MCG_C1_CLKS_M       | // CLKS     = 0,1,2 -> Select FLL/IRCSCLK/ERCLK
             MCG_C1_FRDIV_M      | // FRDIV    = N     -> XTAL/2^n ~ 31.25 kHz
             MCG_C1_IREFS_M      | // IREFS    = 0,1   -> External/Slow IRC for FLL source
             MCG_C1_IRCLKEN_M    | // IRCLKEN  = 0,1   -> IRCLK disable/enable
             MCG_C1_IREFSTEN_M;    // IREFSTEN = 0,1   -> Internal reference enabled in STOP mode

   // Wait for mode change
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_IREFST_MASK) != (MCG_C1_IREFS_V<<MCG_S_IREFST_SHIFT));

#if defined (MCG_C6_PLLS_V) && (MCG_C1_CLKS_V == 0) // FLL or PLL
#define MCG_S_CLKST_M MCG_S_CLKST(MCG_C6_PLLS_V?3:0)
#else
   #define MCG_S_CLKST_M MCG_S_CLKST(MCG_C1_CLKS_V)
#endif

   // Wait for S_CLKST to indicating that OUTCLK has switched
   do {
      __asm__("nop");
   } while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST_M);

   // Set the SIM _CLKDIV dividers
   SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1_M | SIM_CLKDIV1_OUTDIV2_M | SIM_CLKDIV1_OUTDIV3_M | SIM_CLKDIV1_OUTDIV4_M;

#if (CLOCK_MODE == CLOCK_MODE_BLPE) || (CLOCK_MODE == CLOCK_MODE_BLPI)
   // Select BLPE/BLPI clock mode
   MCG_C2 =
            MCG_C2_LOCRE0_M      | // LOCRE0 = 0,1   -> Loss of clock reset
            MCG_C2_RANGE0_M      | // RANGE0 = 0,1,2 -> Oscillator low/high/very high clock range
            MCG_C2_HGO0_M        | // HGO0   = 0,1   -> Oscillator low power/high gain
            MCG_C2_EREFS0_M      | // EREFS0 = 0,1   -> Select external clock/crystal oscillator
            MCG_C2_LP_M          | // LP     = 0,1   -> Select FLL enabled/disabled in bypass mode
            MCG_C2_IRCS_M;         // IRCS   = 0,1   -> Select slow/fast internal clock for internal reference

#endif // (CLOCK_MODE == CLOCK_MODE_BLPE) || (CLOCK_MODE == CLOCK_MODE_BLPI)
#endif // (CLOCK_MODE == CLOCK_MODE_RESET)

   // Basic clock multiplexing
#if defined(MCU_MK20D5) || defined(MCU_MK20D7) || defined(MCU_MK40D10) || defined(MCU_MK40DZ10)
   // Peripheral clock choice (incl. USB), USBCLK = MCGCLK
   SIM_SOPT2 |= SIM_SOPT2_PLLFLLSEL_M    | // PLL rather than FLL for peripheral clock
                SIM_SOPT2_USBSRC_MASK;     // MCGPLLCLK/2 Source as USB clock (48MHz req.)
   SIM_SOPT1 = (SIM_SOPT1&~SIM_SOPT1_OSC32KSEL_MASK)|SIM_SOPT1_OSC32KSEL_M; // ERCLK32K source
#elif defined(MCU_MK60D10) || defined(MCU_MK60DZ10)
   // Peripheral clock choice (incl. USB), USBCLK = MCGCLK
   SIM_SOPT2 |= SIM_SOPT2_PLLFLLSEL_MASK | // PLL rather than FLL for peripheral clock
                SIM_SOPT2_USBSRC_MASK;     // MCGPLLCLK/2 Source as USB clock (48MHz req.)
#elif defined(MCU_MKL24Z4) || defined(MCU_MKL25Z4) || defined(MCU_MKL26Z4) || defined(MCU_MKL46Z4)
   SIM_SOPT2 = SIM_SOPT2_UART0SRC_M      | // UART0 clock - 0,1,2,3 -> Disabled, (MCGFLLCLK, MCGPLLCLK/2),  OSCERCLK, MCGIRCLK
               SIM_SOPT2_TPMSRC_M        | // TPM clock - 0,1,2,3 -> Disabled, (MCGFLLCLK, MCGPLLCLK/2),  OSCERCLK, MCGIRCLK
               SIM_SOPT2_PLLFLLSEL_M     | // Peripheral clock - 0,1 -> MCGFLLCLK,MCGPLLCLK/2
               SIM_SOPT2_USBSRC_MASK;      // MCGPLLCLK/2 Source as USB clock (48MHz req.)
   SIM_SOPT1 = (SIM_SOPT1&~SIM_SOPT1_OSC32KSEL_MASK)|SIM_SOPT1_OSC32KSEL_M; // ERCLK32K clock - 0,1,2,3 -> OSC32KCLK, - , RTC_CLKIN, LPO (1kHz)
#elif defined(MCU_MKL14Z4) || defined(MCU_MKL15Z4) || defined(MCU_MKL16Z4) || defined(MCU_MKL34Z4) || defined(MCU_MKL36Z4)
   SIM_SOPT2 = SIM_SOPT2_UART0SRC_M      | // UART0 clock - 0,1,2,3 -> Disabled, (MCGFLLCLK, MCGPLLCLK/2),  OSCERCLK, MCGIRCLK
               SIM_SOPT2_TPMSRC_M        | // TPM clock - 0,1,2,3 -> Disabled, (MCGFLLCLK, MCGPLLCLK/2),  OSCERCLK, MCGIRCLK
               SIM_SOPT2_PLLFLLSEL_M;      // Peripheral clock - 0,1 -> MCGFLLCLK,MCGPLLCLK/2
   SIM_SOPT1 = (SIM_SOPT1&~SIM_SOPT1_OSC32KSEL_MASK)|SIM_SOPT1_OSC32KSEL_M; // ERCLK32K clock - 0,1,2,3 -> OSC32KCLK, - , RTC_CLKIN, LPO (1kHz)
#elif defined(MCU_MKL02Z4) || defined(MCU_MKL04Z4) || defined(MCU_MKL05Z4)
   SIM_SOPT2 = SIM_SOPT2_UART0SRC_M      | // UART0 clock - 0,1,2,3 -> Disabled, (MCGFLLCLK, MCGPLLCLK/2),  OSCERCLK, MCGIRCLK
               SIM_SOPT2_TPMSRC_M ;        // TPM2 source
#else
   #error "CPU not set"
#endif
   SystemCoreClockUpdate();
}
/*! @brief Sets up the clock out of RESET
 *
 */
void clock_initialise(void) {

#if (CLOCK_MODE == CLOCK_MODE_NONE)
   // No clock setup
#else
   // XTAL/EXTAL Pins
   SIM->SCGC5  |= SIM_SCGC5_PORTA_MASK;
   PORTA->PCR[3]  = PORT_PCR_MUX(0);
   PORTA->PCR[4]  = PORT_PCR_MUX(0);

   // Configure the Crystal Oscillator
   RTC->CR = RTC_CR_WPE_M|RTC_CR_SUP_M|RTC_CR_UM_M|RTC_CR_OSCE_M|RTC_CR_CLKO_M|RTC_CR_SCP_M;

   // Fast Internal Clock divider
   MCG->SC = MCG_SC_FCRDIV_M;

   // Out of reset MCG is in FEI mode
   // =============================================================

   SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1(3) | SIM_CLKDIV1_OUTDIV2(7) | SIM_CLKDIV1_OUTDIV3(3) | SIM_CLKDIV1_OUTDIV4(7);

   // Switch from FEI -> FEI/FBI/FEE/FBE
   // =============================================================

   // Set up crystal or external clock source
   MCG->C2 =
            MCG_C2_LOCRE0_M     | // LOCRE0 = 0,1   -> Loss of clock reset enable
            MCG_C2_RANGE0_M     | // RANGE0 = 0,1,2 -> Oscillator low/high/very high clock range
            MCG_C2_HGO0_M       | // HGO0   = 0,1   -> Oscillator low power/high gain
            MCG_C2_EREFS0_M     | // EREFS0 = 0,1   -> Select external clock/crystal oscillator
            MCG_C2_IRCS_M;        // IRCS   = 0,1   -> Select slow/fast internal clock for internal reference

#if ((CLOCK_MODE == CLOCK_MODE_FEI) || (CLOCK_MODE == CLOCK_MODE_FBI) || (CLOCK_MODE == CLOCK_MODE_BLPI) )
   // Transition via FBI
   //=====================================
#define BYPASS (1) // CLKS value used while FLL locks
   MCG->C1 =  MCG_C1_CLKS(BYPASS)     | // CLKS     = X     -> External reference source while PLL locks
              MCG_C1_FRDIV_M          | // FRDIV    = N     -> XTAL/2^n ~ 31.25 kHz
              MCG_C1_IREFS_M          | // IREFS    = 0,1   -> External/Slow IRC for FLL source
              MCG_C1_IRCLKEN_M        | // IRCLKEN  = 0,1   -> IRCLK disable/enable
              MCG_C1_IREFSTEN_M;        // IREFSTEN = 0,1   -> Internal reference enabled in STOP mode

   // Wait for S_IREFST to indicate FLL Reference has switched
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_IREFST_MASK) != (MCG_C1_IREFS_V<<MCG_S_IREFST_SHIFT));

   // Wait for S_CLKST to indicating that OUTCLK has switched to bypass PLL/FLL
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_CLKST_MASK) != MCG_S_CLKST(BYPASS));

   // Set FLL Parameters
   MCG->C4 = (MCG->C4&~(MCG_C4_DMX32_MASK|MCG_C4_DRST_DRS_MASK))|MCG_C4_DMX32_M|MCG_C4_DRST_DRS_M;
#endif

#if ((CLOCK_MODE == CLOCK_MODE_FBE) || (CLOCK_MODE == CLOCK_MODE_FEE) || (CLOCK_MODE == CLOCK_MODE_PLBE) || (CLOCK_MODE == CLOCK_MODE_PBE) || (CLOCK_MODE == CLOCK_MODE_PEE))

   // Transition via FBE
   //=====================================
#define BYPASS (2) // CLKS value used while PLL locks
   MCG->C1 =  MCG_C1_CLKS(BYPASS)     | // CLKS     = 2     -> External reference source while PLL locks
              MCG_C1_FRDIV_M          | // FRDIV    = N     -> XTAL/2^n ~ 31.25 kHz
              MCG_C1_IREFS_M          | // IREFS    = 0,1   -> External/Slow IRC for FLL source
              MCG_C1_IRCLKEN_M        | // IRCLKEN  = 0,1   -> IRCLK disable/enable
              MCG_C1_IREFSTEN_M;        // IREFSTEN = 0,1   -> Internal reference enabled in STOP mode

#if (MCG_C2_EREFS_V != 0)
   // Wait for oscillator stable (if used)
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_OSCINIT0_MASK) == 0);
#endif

   // Wait for S_IREFST to indicate FLL Reference has switched
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_IREFST_MASK) != (MCG_C1_IREFS_V<<MCG_S_IREFST_SHIFT));

   // Wait for S_CLKST to indicating that OUTCLK has switched to bypass PLL/FLL
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_CLKST_MASK) != MCG_S_CLKST(BYPASS));

   // Set FLL Parameters
   MCG->C4 = (MCG->C4&~(MCG_C4_DMX32_MASK|MCG_C4_DRST_DRS_MASK))|MCG_C4_DMX32_M|MCG_C4_DRST_DRS_M;
#endif

   // Select FEI/FBI/FEE/FBE clock mode
   MCG->C1 =  MCG_C1_CLKS_M       | // CLKS     = 0,1,2 -> Select FLL/IRCSCLK/ERCLK
              MCG_C1_FRDIV_M      | // FRDIV    = N     -> XTAL/2^n ~ 31.25 kHz
              MCG_C1_IREFS_M      | // IREFS    = 0,1   -> External/Slow IRC for FLL source
              MCG_C1_IRCLKEN_M    | // IRCLKEN  = 0,1   -> IRCLK disable/enable
              MCG_C1_IREFSTEN_M;    // IREFSTEN = 0,1   -> Internal reference enabled in STOP mode

   // Wait for mode change
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_IREFST_MASK) != (MCG_C1_IREFS_V<<MCG_S_IREFST_SHIFT));

#if defined (MCG_C6_PLLS_V) && (MCG_C1_CLKS_V == 0) // FLL or PLL
#define MCG_S_CLKST_M MCG_S_CLKST(MCG_C6_PLLS_V?3:0)
#else
   #define MCG_S_CLKST_M MCG_S_CLKST(MCG_C1_CLKS_V)
#endif

   // Wait for S_CLKST to indicating that OUTCLK has switched
   do {
      __asm__("nop");
   } while ((MCG->S & MCG_S_CLKST_MASK) != MCG_S_CLKST_M);

   // Set the SIM _CLKDIV dividers
   SIM->CLKDIV1 = SIM_CLKDIV1_OUTDIV1_M | SIM_CLKDIV1_OUTDIV2_M | SIM_CLKDIV1_OUTDIV3_M | SIM_CLKDIV1_OUTDIV4_M;

#if (CLOCK_MODE == CLOCK_MODE_BLPE) || (CLOCK_MODE == CLOCK_MODE_BLPI)
   // Select BLPE/BLPI clock mode
   MCG->C2 =
            MCG_C2_LOCRE0_M      | // LOCRE0 = 0,1   -> Loss of clock reset
            MCG_C2_RANGE0_M      | // RANGE0 = 0,1,2 -> Oscillator low/high/very high clock range
            MCG_C2_HGO0_M        | // HGO0   = 0,1   -> Oscillator low power/high gain
            MCG_C2_EREFS0_M      | // EREFS0 = 0,1   -> Select external clock/crystal oscillator
            MCG_C2_LP_M          | // LP     = 0,1   -> Select FLL enabled/disabled in bypass mode
            MCG_C2_IRCS_M;         // IRCS   = 0,1   -> Select slow/fast internal clock for internal reference

#endif // (CLOCK_MODE == CLOCK_MODE_BLPE) || (CLOCK_MODE == CLOCK_MODE_BLPI)
#endif // (CLOCK_MODE == CLOCK_MODE_NONE)


   /*!
    * SOPT1 Clock multiplexing
    */
#if defined(SIM_SOPT1_OSC32KSEL_MASK) && defined(SIM_SOPT1_OSC32KSEL_M) // ERCLK32K source
   SIM->SOPT1 = (SIM->SOPT1&~SIM_SOPT1_OSC32KSEL_MASK)|SIM_SOPT1_OSC32KSEL_M;
#endif

   /*!
    * SOPT2 Clock multiplexing
    */
#if defined(SIM_SOPT2_SDHCSRC_MASK) && defined(SIM_SOPT2_SDHCSRC_M) // SDHC clock
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_SDHCSRC_MASK)|SIM_SOPT2_SDHCSRC_M;
#endif

#if defined(SIM_SOPT2_TIMESRC_MASK) && defined(SIM_SOPT2_TIMESRC_M) // Ethernet time-stamp clock
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_TIMESRC_MASK)|SIM_SOPT2_TIMESRC_M;
#endif

#if defined(SIM_SOPT2_RMIISRC_MASK) && defined(SIM_SOPT2_RMIISRC_M) // RMII clock
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_RMIISRC_MASK)|SIM_SOPT2_RMIISRC_M;
#endif

#ifdef SIM_SCGC4_USBOTG_MASK
   // !! WARNING !! The USB interface must be disabled for clock changes to have effect !! WARNING !!
   SIM->SCGC4 &= ~SIM_SCGC4_USBOTG_MASK;
#endif

#if defined(SIM_SOPT2_USBSRC_MASK) && defined(SIM_SOPT2_USBSRC_M) // USB clock (48MHz req.)
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_USBSRC_MASK)|SIM_SOPT2_USBSRC_M;
#endif

#if defined(SIM_SOPT2_USBFSRC_MASK) && defined(SIM_SOPT2_USBFSRC_M) // USB clock (48MHz req.)
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_USBFSRC_MASK)|SIM_SOPT2_USBFSRC_M;
#endif

#if defined(SIM_SOPT2_PLLFLLSEL_MASK) && defined(SIM_SOPT2_PLLFLLSEL_M) // Peripheral clock
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_PLLFLLSEL_MASK)|SIM_SOPT2_PLLFLLSEL_M;
#endif

#if defined(SIM_SOPT2_UART0SRC_MASK) && defined(SIM_SOPT2_UART0SRC_M) // UART0 clock
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_UART0SRC_MASK)|SIM_SOPT2_UART0SRC_M;
#endif

#if defined(SIM_SOPT2_TPMSRC_MASK) && defined(SIM_SOPT2_TPMSRC_M) // TPM clock
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_TPMSRC_MASK)|SIM_SOPT2_TPMSRC_M;
#endif

#if defined(SIM_SOPT2_CLKOUTSEL_MASK) && defined(SIM_SOPT2_CLKOUTSEL_M)
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_CLKOUTSEL_MASK)|SIM_SOPT2_CLKOUTSEL_M;
#endif

#if defined(SIM_SOPT2_RTCCLKOUTSEL_MASK) && defined(SIM_SOPT2_RTCCLKOUTSEL_M)
   SIM->SOPT2 = (SIM->SOPT2&~SIM_SOPT2_RTCCLKOUTSEL_MASK)|SIM_SOPT2_RTCCLKOUTSEL_M;
#endif

#if defined(SIM_CLKDIV2_USBDIV_MASK) && defined(SIM_CLKDIV2_USBFRAC_MASK) && defined(SIM_CLKDIV2_USB_M)
   SIM->CLKDIV2 = (SIM->CLKDIV2&~(SIM_CLKDIV2_USBDIV_MASK|SIM_CLKDIV2_USBFRAC_MASK)) | SIM_CLKDIV2_USB_M;
#endif

   SystemCoreClockUpdate();
}
void ResetHandler(void)
{
        uint32_t *src = &_etext;
        uint32_t *dest = &_sdata;

	WDOG_UNLOCK = WDOG_UNLOCK_SEQ1;
	WDOG_UNLOCK = WDOG_UNLOCK_SEQ2;
	WDOG_STCTRLH = WDOG_STCTRLH_ALLOWUPDATE;
	startup_early_hook();

	// enable clocks to always-used peripherals
	SIM_SCGC5 = 0x00043F82;		// clocks active to all GPIO
	SIM_SCGC6 = SIM_SCGC6_RTC | SIM_SCGC6_FTM0 | SIM_SCGC6_FTM1 | SIM_SCGC6_ADC0 | SIM_SCGC6_FTFL;
	// if the RTC oscillator isn't enabled, get it started early
	if (!(RTC_CR & RTC_CR_OSCE)) {
		RTC_SR = 0;
		RTC_CR = RTC_CR_SC16P | RTC_CR_SC4P | RTC_CR_OSCE;
	}

	// TODO: do this while the PLL is waiting to lock....
        while (dest < &_edata) *dest++ = *src++;
        dest = &_sbss;
        while (dest < &_ebss) *dest++ = 0;
	SCB_VTOR = 0;	// use vector table in flash

        // start in FEI mode
        // enable capacitors for crystal
        OSC0_CR = OSC_SC8P | OSC_SC2P;
        // enable osc, 8-32 MHz range, low power mode
        MCG_C2 = MCG_C2_RANGE0(2) | MCG_C2_EREFS;
        // switch to crystal as clock source, FLL input = 16 MHz / 512
        MCG_C1 =  MCG_C1_CLKS(2) | MCG_C1_FRDIV(4);
        // wait for crystal oscillator to begin
        while ((MCG_S & MCG_S_OSCINIT0) == 0) ;
        // wait for FLL to use oscillator
        while ((MCG_S & MCG_S_IREFST) != 0) ;
        // wait for MCGOUT to use oscillator
        while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(2)) ;
        // now we're in FBE mode
        // config PLL input for 16 MHz Crystal / 4 = 4 MHz
        MCG_C5 = MCG_C5_PRDIV0(3);
        // config PLL for 96 MHz output
        MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(0);
        // wait for PLL to start using xtal as its input
        while (!(MCG_S & MCG_S_PLLST)) ;
        // wait for PLL to lock
        while (!(MCG_S & MCG_S_LOCK0)) ;
        // now we're in PBE mode
#if F_CPU == 96000000
        // config divisors: 96 MHz core, 48 MHz bus, 24 MHz flash
        SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(1) |  SIM_CLKDIV1_OUTDIV4(3);
#elif F_CPU == 48000000
        // config divisors: 48 MHz core, 48 MHz bus, 24 MHz flash
        SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(1) | SIM_CLKDIV1_OUTDIV2(1) |  SIM_CLKDIV1_OUTDIV4(3);
#elif F_CPU == 24000000
        // config divisors: 24 MHz core, 24 MHz bus, 24 MHz flash
        SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(3) | SIM_CLKDIV1_OUTDIV2(3) |  SIM_CLKDIV1_OUTDIV4(3);
#else
#error "Error, F_CPU must be 96000000, 48000000, or 24000000"
#endif
        // switch to PLL as clock source, FLL input = 16 MHz / 512
        MCG_C1 = MCG_C1_CLKS(0) | MCG_C1_FRDIV(4);
        // wait for PLL clock to be used
        while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(3)) ;
        // now we're in PEE mode
        // configure USB for 48 MHz clock
        SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(1); // USB = 96 MHz PLL / 2
        // USB uses PLL clock, trace is CPU clock, CLKOUT=OSCERCLK0
        SIM_SOPT2 = SIM_SOPT2_USBSRC | SIM_SOPT2_PLLFLLSEL | SIM_SOPT2_TRACECLKSEL | SIM_SOPT2_CLKOUTSEL(6);

        // initialize the SysTick counter
        SYST_RVR = (F_CPU / 1000) - 1;
        SYST_CSR = SYST_CSR_CLKSOURCE | SYST_CSR_TICKINT | SYST_CSR_ENABLE;

	//init_pins();
	__enable_irq();

	_init_Teensyduino_internal_();
	if (RTC_SR & RTC_SR_TIF) rtc_set(TIME_T);

	__libc_init_array();

/*
	for (ptr = &__init_array_start; ptr < &__init_array_end; ptr++) {
		(*ptr)();
	}
*/
	startup_late_hook();
        main();
        while (1) ;
}
Beispiel #29
0
/*lint -esym(765,Cpu_Interrupt) Disable MISRA rule (8.10) checking for symbols (Cpu_Interrupt). */
void __init_hardware(void)
{

  /*** !!! Here you can place your own code before PE initialization using property "User code before PE initialization" on the build options tab. !!! ***/

  /*** ### MK22FX512VLQ12 "Cpu" init code ... ***/
  /*** PE initialization code after reset ***/
  SCB_VTOR = (uint32_t)(&__vect_table); /* Set the interrupt vector table position */
  /* Disable the WDOG module */
  /* WDOG_UNLOCK: WDOGUNLOCK=0xC520 */
  WDOG_UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xC520); /* Key 1 */
  /* WDOG_UNLOCK: WDOGUNLOCK=0xD928 */
  WDOG_UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xD928); /* Key 2 */
  /* WDOG_STCTRLH: ??=0,DISTESTWDOG=0,BYTESEL=0,TESTSEL=0,TESTWDOG=0,??=0,??=1,WAITEN=1,STOPEN=1,DBGEN=0,ALLOWUPDATE=1,WINEN=0,IRQRSTEN=0,CLKSRC=1,WDOGEN=0 */
  WDOG_STCTRLH = WDOG_STCTRLH_BYTESEL(0x00) |
                 WDOG_STCTRLH_WAITEN_MASK |
                 WDOG_STCTRLH_STOPEN_MASK |
                 WDOG_STCTRLH_ALLOWUPDATE_MASK |
                 WDOG_STCTRLH_CLKSRC_MASK |
                 0x0100U;

  /* System clock initialization */
  /* SIM_CLKDIV1: OUTDIV1=0,OUTDIV2=1,OUTDIV3=3,OUTDIV4=3,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0 */
  SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0x00) |
                SIM_CLKDIV1_OUTDIV2(0x01) |
                SIM_CLKDIV1_OUTDIV3(0x03) |
                SIM_CLKDIV1_OUTDIV4(0x03); /* Set the system prescalers to safe value */
  /* SIM_SCGC5: PORTE=1,PORTD=1,PORTB=1,PORTA=1 */
  SIM_SCGC5 |= SIM_SCGC5_PORTE_MASK |
               SIM_SCGC5_PORTD_MASK |
               SIM_SCGC5_PORTB_MASK |
               SIM_SCGC5_PORTA_MASK;   /* Enable clock gate for ports to enable pin routing */
  /* SIM_SCGC5: LPTMR=1 */
  SIM_SCGC5 |= SIM_SCGC5_LPTMR_MASK;
  if ((PMC_REGSC & PMC_REGSC_ACKISO_MASK) != 0x0U) {
    /* PMC_REGSC: ACKISO=1 */
    PMC_REGSC |= PMC_REGSC_ACKISO_MASK; /* Release IO pads after wakeup from VLLS mode. */
  }
  /* SIM_CLKDIV1: OUTDIV1=0,OUTDIV2=1,OUTDIV3=4,OUTDIV4=4,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0,??=0 */
  SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0x00) |
                SIM_CLKDIV1_OUTDIV2(0x01) |
                SIM_CLKDIV1_OUTDIV3(0x04) |
                SIM_CLKDIV1_OUTDIV4(0x04); /* Update system prescalers */
  /* SIM_SOPT2: PLLFLLSEL=1 */
  SIM_SOPT2 |= SIM_SOPT2_PLLFLLSEL_MASK; /* Select PLL as a clock source for various peripherals */
  /* SIM_SOPT1: OSC32KSEL=3 */
  SIM_SOPT1 |= SIM_SOPT1_OSC32KSEL(0x03); /* LPO 1kHz oscillator drives 32 kHz clock for various peripherals */
  /* PORTA_PCR18: ISF=0,MUX=0 */
  PORTA_PCR18 &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));
  /* PORTA_PCR19: ISF=0,MUX=0 */
  PORTA_PCR19 &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));
  /* Switch to FBE Mode */
  /* MCG_C2: LOCRE0=0,??=0,RANGE0=2,HGO0=0,EREFS0=1,LP=0,IRCS=0 */
  MCG_C2 = (MCG_C2_RANGE0(0x02) | MCG_C2_EREFS0_MASK);
  /* OSC_CR: ERCLKEN=1,??=0,EREFSTEN=0,??=0,SC2P=0,SC4P=0,SC8P=0,SC16P=0 */
  OSC_CR = OSC_CR_ERCLKEN_MASK;
  /* MCG_C7: OSCSEL=0 */
  MCG_C7 &= (uint8_t)~(uint8_t)(MCG_C7_OSCSEL_MASK);
  /* MCG_C1: CLKS=2,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0 */
  MCG_C1 = (MCG_C1_CLKS(0x02) | MCG_C1_FRDIV(0x03) | MCG_C1_IRCLKEN_MASK);
  /* MCG_C4: DMX32=0,DRST_DRS=0 */
  MCG_C4 &= (uint8_t)~(uint8_t)((MCG_C4_DMX32_MASK | MCG_C4_DRST_DRS(0x03)));
  /* MCG_C5: ??=0,PLLCLKEN0=0,PLLSTEN0=0,PRDIV0=1 */
  MCG_C5 = MCG_C5_PRDIV0(0x01);
  /* MCG_C6: LOLIE0=0,PLLS=0,CME0=0,VDIV0=6 */
  MCG_C6 = MCG_C6_VDIV0(0x06);
  while((MCG_S & MCG_S_OSCINIT0_MASK) == 0x00U) { /* Check that the oscillator is running */
  }
  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_C1: CLKS=2,FRDIV=4,IREFS=0,IRCLKEN=1,IREFSTEN=0 */
  MCG_C1 = (MCG_C1_CLKS(0x02) | MCG_C1_FRDIV(0x04) | MCG_C1_IRCLKEN_MASK);
  /* MCG_C6: LOLIE0=0,PLLS=1,CME0=0,VDIV0=6 */
  MCG_C6 = (MCG_C6_PLLS_MASK | MCG_C6_VDIV0(0x06));
  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=4,IREFS=0,IRCLKEN=1,IREFSTEN=0 */
  MCG_C1 = (MCG_C1_CLKS(0x00) | MCG_C1_FRDIV(0x04) | MCG_C1_IRCLKEN_MASK);
  while((MCG_S & 0x0CU) != 0x0CU) {    /* Wait until output of the PLL is selected */
  }
  /*** End of PE initialization code after reset ***/

  /*** !!! Here you can place your own code after PE initialization using property "User code after PE initialization" on the build options tab. !!! ***/

}
Beispiel #30
0
/************************************************************************************************ 
* SetPLL_Kinetis
* 系统的锁相环设定,其完成的主要工作为: 设定CoreClock、BusClock、FlexClock、FlashClock
* (设置的具体频率在KinetisConfig.h中配置)
************************************************************************************************/
static void SetPLL_Kinetis(void)
{
  K_int32u_t temp_reg;
  K_int8u_t  i;
// First move to FBE mode
// Enable external oscillator, RANGE=2, HGO=1, EREFS=1, LP=0, IRCS=0
  MCG_C2 = MCG_C2_RANGE(1) | MCG_C2_HGO_MASK | MCG_C2_EREFS_MASK;

// after initialization of oscillator release latched state of oscillator and GPIO
  SIM_SCGC4 |= SIM_SCGC4_LLWU_MASK;
  LLWU_CS |= LLWU_CS_ACKISO_MASK;
  
// Select external oscilator and Reference Divider and clear IREFS to start ext osc
// CLKS=2, FRDIV=3, IREFS=0, IRCLKEN=0, IREFSTEN=0
  MCG_C1 = MCG_C1_CLKS(2) | MCG_C1_FRDIV(3);

  /* if we aren't using an osc input we don't need to wait for the osc to init */

  while (MCG_S & MCG_S_IREFST_MASK){}; // wait for Reference clock Status bit to clear

  while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x2){}; // Wait for clock status bits to show clock source is ext ref clk

// Now in FBE

  /* 设定PLL时钟 */
#if CORE_CLK_Kinetis  <= 110
  MCG_C5 = MCG_C5_PRDIV(REF_CLK_Kinetis/2 - 1);     /* PLLCLK == 2MHz */
#else
  #if   REF_CLK_Kinetis % 3 == 0
    MCG_C5 = MCG_C5_PRDIV(REF_CLK_Kinetis/3 - 1);   /* PLLCLK == 3MHz */
  #elif REF_CLK_Kinetis % 4 == 0
    MCG_C5 = MCG_C5_PRDIV(REF_CLK_Kinetis/4 - 1);   /* PLLCLK == 4MHz */
  #elif REF_CLK_Kinetis % 5 == 0
    MCG_C5 = MCG_C5_PRDIV(REF_CLK_Kinetis*2/5 - 1); /* PLLCLK == 2.5MHz */
  #endif
#endif 
  /*
   * Ensure MCG_C6 is at the reset default of 0. LOLIE disabled,
   * PLL disabled, clk monitor disabled, PLL VCO divider is clear 
   */  
  MCG_C6 = 0x0;

  /* 设定各时钟的分频数 */
  temp_reg = FMC_PFAPR; // store present value of FMC_PFAPR
  // set M0PFD through M7PFD to 1 to disable prefetch
  FMC_PFAPR |= FMC_PFAPR_M7PFD_MASK | FMC_PFAPR_M6PFD_MASK | FMC_PFAPR_M5PFD_MASK
             | FMC_PFAPR_M4PFD_MASK | FMC_PFAPR_M3PFD_MASK | FMC_PFAPR_M2PFD_MASK
             | FMC_PFAPR_M1PFD_MASK | FMC_PFAPR_M0PFD_MASK;
  
  // set clock dividers to desired value  
  SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0)       
              | SIM_CLKDIV1_OUTDIV2(DIV_BusClk_Kinetis - 1) 
              | SIM_CLKDIV1_OUTDIV3(DIV_FlexClk_Kinetis - 1) 
              | SIM_CLKDIV1_OUTDIV4(DIV_FlashClk_Kinetis - 1);
  // wait for dividers to change
  for (i = 0 ; i < DIV_FlashClk_Kinetis ; i++) {}
  FMC_PFAPR = temp_reg; // re-store original value of FMC_PFAPR  
  
  /* 设置倍频数,倍频数为VDIV+24 */
#if CORE_CLK_Kinetis  <= 110
  MCG_C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV(CORE_CLK_Kinetis/2 - 24); 
#else
  #if   REF_CLK_Kinetis % 3 == 0
    MCG_C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV(CORE_CLK_Kinetis/3 - 24); 
  #elif REF_CLK_Kinetis % 4 == 0
    MCG_C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV(CORE_CLK_Kinetis/4 - 24);
  #elif REF_CLK_Kinetis % 5 == 0
    MCG_C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV(CORE_CLK_Kinetis*2/5 - 24); 
  #endif
#endif
  
  while (!(MCG_S & MCG_S_PLLST_MASK)){}; // wait for PLL status bit to set

  while (!(MCG_S & MCG_S_LOCK_MASK)){}; // Wait for LOCK bit to set

// Now running PBE Mode

// Transition into PEE by setting CLKS to 0
// CLKS=0, FRDIV=3, IREFS=0, IRCLKEN=0, IREFSTEN=0
  MCG_C1 &= ~MCG_C1_CLKS_MASK;

// Wait for clock status bits to update
  while (((MCG_S & MCG_S_CLKST_MASK) >> MCG_S_CLKST_SHIFT) != 0x3){};
}