コード例 #1
0
ファイル: system_nrf52.c プロジェクト: MarceloSalazar/mbed-os
void SystemInit(void)
{
    /* Enable SWO trace functionality. If ENABLE_SWO is not defined, SWO pin will be used as GPIO (see Product
       Specification to see which one). */
#if defined (ENABLE_SWO)
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Serial << CLOCK_TRACECONFIG_TRACEMUX_Pos;
        NRF_P0->PIN_CNF[18] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
#endif

    /* Enable Trace functionality. If ENABLE_TRACE is not defined, TRACE pins will be used as GPIOs (see Product
       Specification to see which ones). */
#if defined (ENABLE_TRACE)
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Parallel << CLOCK_TRACECONFIG_TRACEMUX_Pos;
        NRF_P0->PIN_CNF[14] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[15] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[16] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[18] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[20] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
#endif
    
    /* Workaround for Errata 12 "COMP: Reference ladder not correctly calibrated" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/ */
    if (errata_12()){
        *(volatile uint32_t *)0x40013540 = (*(uint32_t *)0x10000324 & 0x00001F00) >> 8;
    }
    
    /* Workaround for Errata 16 "System: RAM may be corrupt on wakeup from CPU IDLE" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/ */
    if (errata_16()){
        *(volatile uint32_t *)0x4007C074 = 3131961357ul;
    }

    /* Workaround for Errata 31 "CLOCK: Calibration values are not correctly loaded from FICR at reset" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/ */
    if (errata_31()){
        *(volatile uint32_t *)0x4000053C = ((*(volatile uint32_t *)0x10000244) & 0x0000E000) >> 13;
    }

    /* Workaround for Errata 32 "DIF: Debug session automatically enables TracePort pins" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/ */
    if (errata_32()){
        CoreDebug->DEMCR &= ~CoreDebug_DEMCR_TRCENA_Msk;
    }

    /* Workaround for Errata 36 "CLOCK: Some registers are not reset when expected" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_36()){
        NRF_CLOCK->EVENTS_DONE = 0;
        NRF_CLOCK->EVENTS_CTTO = 0;
        NRF_CLOCK->CTIV = 0;
    }

    /* Workaround for Errata 37 "RADIO: Encryption engine is slow by default" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_37()){
        *(volatile uint32_t *)0x400005A0 = 0x3;
    }

    /* Workaround for Errata 57 "NFCT: NFC Modulation amplitude" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_57()){
        *(volatile uint32_t *)0x40005610 = 0x00000005;
        *(volatile uint32_t *)0x40005688 = 0x00000001;
        *(volatile uint32_t *)0x40005618 = 0x00000000;
        *(volatile uint32_t *)0x40005614 = 0x0000003F;
    }

    /* Workaround for Errata 66 "TEMP: Linearity specification not met with default settings" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_66()){
        NRF_TEMP->A0 = NRF_FICR->TEMP.A0;
        NRF_TEMP->A1 = NRF_FICR->TEMP.A1;
        NRF_TEMP->A2 = NRF_FICR->TEMP.A2;
        NRF_TEMP->A3 = NRF_FICR->TEMP.A3;
        NRF_TEMP->A4 = NRF_FICR->TEMP.A4;
        NRF_TEMP->A5 = NRF_FICR->TEMP.A5;
        NRF_TEMP->B0 = NRF_FICR->TEMP.B0;
        NRF_TEMP->B1 = NRF_FICR->TEMP.B1;
        NRF_TEMP->B2 = NRF_FICR->TEMP.B2;
        NRF_TEMP->B3 = NRF_FICR->TEMP.B3;
        NRF_TEMP->B4 = NRF_FICR->TEMP.B4;
        NRF_TEMP->B5 = NRF_FICR->TEMP.B5;
        NRF_TEMP->T0 = NRF_FICR->TEMP.T0;
        NRF_TEMP->T1 = NRF_FICR->TEMP.T1;
        NRF_TEMP->T2 = NRF_FICR->TEMP.T2;
        NRF_TEMP->T3 = NRF_FICR->TEMP.T3;
        NRF_TEMP->T4 = NRF_FICR->TEMP.T4;
    }

    /* Workaround for Errata 108 "RAM: RAM content cannot be trusted upon waking up from System ON Idle or System OFF mode" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_108()){
        *(volatile uint32_t *)0x40000EE4 = *(volatile uint32_t *)0x10000258 & 0x0000004F;
    }
    
    /* Workaround for Errata 136 "System: Bits in RESETREAS are set when they should not be" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_136()){
        if (NRF_POWER->RESETREAS & POWER_RESETREAS_RESETPIN_Msk){
            NRF_POWER->RESETREAS =  ~POWER_RESETREAS_RESETPIN_Msk;
        }
    }
    
    /* Enable the FPU if the compiler used floating point unit instructions. __FPU_USED is a MACRO defined by the
     * compiler. Since the FPU consumes energy, remember to disable FPU use in the compiler if floating point unit
     * operations are not used in your code. */
#if (__FPU_USED == 1)
        SCB->CPACR |= (3UL << 20) | (3UL << 22);
        __DSB();
        __ISB();
#endif

    /* Configure NFCT pins as GPIOs if NFCT is not to be used in your code. If CONFIG_NFCT_PINS_AS_GPIOS is not defined,
       two GPIOs (see Product Specification to see which ones) will be reserved for NFC and will not be available as
       normal GPIOs. */
#if defined (CONFIG_NFCT_PINS_AS_GPIOS)
        if ((NRF_UICR->NFCPINS & UICR_NFCPINS_PROTECT_Msk) == (UICR_NFCPINS_PROTECT_NFC << UICR_NFCPINS_PROTECT_Pos)){
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->NFCPINS &= ~UICR_NFCPINS_PROTECT_Msk;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NVIC_SystemReset();
        }
#endif

    /* Configure GPIO pads as pPin Reset pin if Pin Reset capabilities desired. If CONFIG_GPIO_AS_PINRESET is not
      defined, pin reset will not be available. One GPIO (see Product Specification to see which one) will then be
      reserved for PinReset and not available as normal GPIO. */
#if defined (CONFIG_GPIO_AS_PINRESET)
        if (((NRF_UICR->PSELRESET[0] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos)) ||
            ((NRF_UICR->PSELRESET[1] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos))){
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[0] = 21;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[1] = 21;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NVIC_SystemReset();
        }
#endif

    SystemCoreClockUpdate();

    // Start the LF oscilator according to the mbed configuration (over the nrf5x_lf_clk_helper.h file)
    NRF_CLOCK->LFCLKSRC             = (CLOCK_LFCLKSRC_SRC_TO_USE << CLOCK_LFCLKSRC_SRC_Pos);
    NRF_CLOCK->EVENTS_LFCLKSTARTED  = 0;
    NRF_CLOCK->TASKS_LFCLKSTART     = 1;

    // Wait for the external oscillator to start up.
    while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0) {
        // Do nothing.
    }

    /**
     * Mbed HAL specific code section.
     *
     * The ITM has to be initialized before the SoftDevice which weren't guaranteed using the normal API.
     */
#if defined (DEVICE_ITM)
        /* Enable SWO trace functionality */
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Serial << CLOCK_TRACECONFIG_TRACEMUX_Pos;

        /* set SWO clock speed to 4 MHz */
        NRF_CLOCK->TRACECONFIG = (NRF_CLOCK->TRACECONFIG & ~CLOCK_TRACECONFIG_TRACEPORTSPEED_Msk) |
                                 (CLOCK_TRACECONFIG_TRACEPORTSPEED_4MHz << CLOCK_TRACECONFIG_TRACEPORTSPEED_Pos);

        /* set SWO pin */
        NRF_P0->PIN_CNF[18] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) |
                              (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
                              (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);

        /* set prescaler */
        TPI->ACPR = 0;
#endif
}
コード例 #2
0
ファイル: system_nrf52810.c プロジェクト: abtink/openthread
void SystemInit(void)
{
    /* Enable SWO trace functionality. If ENABLE_SWO is not defined, SWO pin will be used as GPIO (see Product
       Specification to see which one). Only available if the developing environment is an nRF52832 device. */
    #if defined (DEVELOP_IN_NRF52832) && defined (ENABLE_SWO)
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Serial << CLOCK_TRACECONFIG_TRACEMUX_Pos;
        NRF_P0->PIN_CNF[18] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
    #endif
    
    /* Enable Trace functionality. If ENABLE_TRACE is not defined, TRACE pins will be used as GPIOs (see Product
       Specification to see which ones). Only available if the developing environment is an nRF52832 device. */
    #if defined (DEVELOP_IN_NRF52832) && defined (ENABLE_TRACE)
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Parallel << CLOCK_TRACECONFIG_TRACEMUX_Pos;
        NRF_P0->PIN_CNF[14] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[15] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[16] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[18] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[20] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
    #endif
    
    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 12 "COMP: Reference ladder not correctly calibrated" found at the Errata document
       for nRF52832 device located at https://www.nordicsemi.com/DocLib */
    if (errata_12()){
        *(volatile uint32_t *)0x40013540 = (*(uint32_t *)0x10000324 & 0x00001F00) >> 8;
    }
    #endif
    
    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 16 "System: RAM may be corrupt on wakeup from CPU IDLE" found at the Errata document
       for nRF52832 device located at https://www.nordicsemi.com/DocLib */
    if (errata_16()){
        *(volatile uint32_t *)0x4007C074 = 3131961357ul;
    }
    #endif
    
    /* Workaround for Errata 31 "CLOCK: Calibration values are not correctly loaded from FICR at reset" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib */
    if (errata_31()){
        *(volatile uint32_t *)0x4000053C = ((*(volatile uint32_t *)0x10000244) & 0x0000E000) >> 13;
    }

    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 32 "DIF: Debug session automatically enables TracePort pins" found at the Errata document
       for nRF52832 device located at https://www.nordicsemi.com/DocLib */
    if (errata_32()){
        CoreDebug->DEMCR &= ~CoreDebug_DEMCR_TRCENA_Msk;
    }
    #endif
    
    /* Workaround for Errata 36 "CLOCK: Some registers are not reset when expected" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_36()){
        NRF_CLOCK->EVENTS_DONE = 0;
        NRF_CLOCK->EVENTS_CTTO = 0;
        NRF_CLOCK->CTIV = 0;
    }
    
    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 37 "RADIO: Encryption engine is slow by default" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_37()){
        *(volatile uint32_t *)0x400005A0 = 0x3;
    }
    #endif

    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 57 "NFCT: NFC Modulation amplitude" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_57()){
        *(volatile uint32_t *)0x40005610 = 0x00000005;
        *(volatile uint32_t *)0x40005688 = 0x00000001;
        *(volatile uint32_t *)0x40005618 = 0x00000000;
        *(volatile uint32_t *)0x40005614 = 0x0000003F;
    }
    #endif
    
    /* Workaround for Errata 66 "TEMP: Linearity specification not met with default settings" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_66()){
        NRF_TEMP->A0 = NRF_FICR->TEMP.A0;
        NRF_TEMP->A1 = NRF_FICR->TEMP.A1;
        NRF_TEMP->A2 = NRF_FICR->TEMP.A2;
        NRF_TEMP->A3 = NRF_FICR->TEMP.A3;
        NRF_TEMP->A4 = NRF_FICR->TEMP.A4;
        NRF_TEMP->A5 = NRF_FICR->TEMP.A5;
        NRF_TEMP->B0 = NRF_FICR->TEMP.B0;
        NRF_TEMP->B1 = NRF_FICR->TEMP.B1;
        NRF_TEMP->B2 = NRF_FICR->TEMP.B2;
        NRF_TEMP->B3 = NRF_FICR->TEMP.B3;
        NRF_TEMP->B4 = NRF_FICR->TEMP.B4;
        NRF_TEMP->B5 = NRF_FICR->TEMP.B5;
        NRF_TEMP->T0 = NRF_FICR->TEMP.T0;
        NRF_TEMP->T1 = NRF_FICR->TEMP.T1;
        NRF_TEMP->T2 = NRF_FICR->TEMP.T2;
        NRF_TEMP->T3 = NRF_FICR->TEMP.T3;
        NRF_TEMP->T4 = NRF_FICR->TEMP.T4;
    }
    
    /* Workaround for Errata 103 "CCM: Wrong reset value of CCM MAXPACKETSIZE" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_103()){
        NRF_CCM->MAXPACKETSIZE = 0xFBul;
    }
    
    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 108 "RAM: RAM content cannot be trusted upon waking up from System ON Idle or System OFF mode" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_108()){
        *(volatile uint32_t *)0x40000EE4 = *(volatile uint32_t *)0x10000258 & 0x0000004F;
    }
    #endif
    
    /* Workaround for Errata 136 "System: Bits in RESETREAS are set when they should not be" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_136()){
        if (NRF_POWER->RESETREAS & POWER_RESETREAS_RESETPIN_Msk){
            NRF_POWER->RESETREAS =  ~POWER_RESETREAS_RESETPIN_Msk;
        }
    }
    
    #if defined (DEVELOP_IN_NRF52832)
    /* Workaround for Errata 182 "RADIO: Fixes for anomalies #102, #106, and #107 do not take effect" found at the Errata document
       for your device located at https://www.nordicsemi.com/DocLib  */
    if (errata_182()){
        *(volatile uint32_t *) 0x4000173C |= (0x1 << 10);
    }
    #endif

    /* Configure GPIO pads as pPin Reset pin if Pin Reset capabilities desired. If CONFIG_GPIO_AS_PINRESET is not
      defined, pin reset will not be available. One GPIO (see Product Specification to see which one) will then be
      reserved for PinReset and not available as normal GPIO. */
    #if defined (CONFIG_GPIO_AS_PINRESET)
        if (((NRF_UICR->PSELRESET[0] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos)) ||
            ((NRF_UICR->PSELRESET[1] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos))){
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[0] = 21;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[1] = 21;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NVIC_SystemReset();
        }
    #endif

    SystemCoreClockUpdate();
}
コード例 #3
0
void SystemInit(void)
{
    /* Enable SWO trace functionality. If ENABLE_SWO is not defined, SWO pin will be used as GPIO (see Product
       Specification to see which one). */
#if defined (ENABLE_SWO)
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Serial << CLOCK_TRACECONFIG_TRACEMUX_Pos;
        NRF_P1->PIN_CNF[0] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
#endif

    /* Enable Trace functionality. If ENABLE_TRACE is not defined, TRACE pins will be used as GPIOs (see Product
       Specification to see which ones). */
#if defined (ENABLE_TRACE)
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Parallel << CLOCK_TRACECONFIG_TRACEMUX_Pos;
        NRF_P0->PIN_CNF[7]  = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P1->PIN_CNF[0]  = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[12] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P0->PIN_CNF[11] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
        NRF_P1->PIN_CNF[9]  = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
#endif

    /* Workaround for Errata 36 "CLOCK: Some registers are not reset when expected" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_36()){
        NRF_CLOCK->EVENTS_DONE = 0;
        NRF_CLOCK->EVENTS_CTTO = 0;
        NRF_CLOCK->CTIV = 0;
    }
    
    /* Workaround for Errata 66 "TEMP: Linearity specification not met with default settings" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_66()){
        NRF_TEMP->A0 = NRF_FICR->TEMP.A0;
        NRF_TEMP->A1 = NRF_FICR->TEMP.A1;
        NRF_TEMP->A2 = NRF_FICR->TEMP.A2;
        NRF_TEMP->A3 = NRF_FICR->TEMP.A3;
        NRF_TEMP->A4 = NRF_FICR->TEMP.A4;
        NRF_TEMP->A5 = NRF_FICR->TEMP.A5;
        NRF_TEMP->B0 = NRF_FICR->TEMP.B0;
        NRF_TEMP->B1 = NRF_FICR->TEMP.B1;
        NRF_TEMP->B2 = NRF_FICR->TEMP.B2;
        NRF_TEMP->B3 = NRF_FICR->TEMP.B3;
        NRF_TEMP->B4 = NRF_FICR->TEMP.B4;
        NRF_TEMP->B5 = NRF_FICR->TEMP.B5;
        NRF_TEMP->T0 = NRF_FICR->TEMP.T0;
        NRF_TEMP->T1 = NRF_FICR->TEMP.T1;
        NRF_TEMP->T2 = NRF_FICR->TEMP.T2;
        NRF_TEMP->T3 = NRF_FICR->TEMP.T3;
        NRF_TEMP->T4 = NRF_FICR->TEMP.T4;
    }
    
    /* Workaround for Errata 98 "NFCT: Not able to communicate with the peer" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_98()){
        *(volatile uint32_t *)0x4000568Cul = 0x00038148ul;
    }
    
    /* Workaround for Errata 103 "CCM: Wrong reset value of CCM MAXPACKETSIZE" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_103()){
        NRF_CCM->MAXPACKETSIZE = 0xFBul;
    }
    
    /* Workaround for Errata 115 "RAM: RAM content cannot be trusted upon waking up from System ON Idle or System OFF mode" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_115()){
        *(volatile uint32_t *)0x40000EE4 = (*(volatile uint32_t *)0x40000EE4 & 0xFFFFFFF0) | (*(uint32_t *)0x10000258 & 0x0000000F);
    }
    
    /* Workaround for Errata 120 "QSPI: Data read or written is corrupted" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_120()){
        *(volatile uint32_t *)0x40029640ul = 0x200ul;
    }
    
    /* Workaround for Errata 136 "System: Bits in RESETREAS are set when they should not be" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/  */
    if (errata_136()){
        if (NRF_POWER->RESETREAS & POWER_RESETREAS_RESETPIN_Msk){
            NRF_POWER->RESETREAS =  ~POWER_RESETREAS_RESETPIN_Msk;
        }
    }
    
    /* Enable the FPU if the compiler used floating point unit instructions. __FPU_USED is a MACRO defined by the
     * compiler. Since the FPU consumes energy, remember to disable FPU use in the compiler if floating point unit
     * operations are not used in your code. */
#if (__FPU_USED == 1)
        SCB->CPACR |= (3UL << 20) | (3UL << 22);
        __DSB();
        __ISB();
#endif

    /* Configure NFCT pins as GPIOs if NFCT is not to be used in your code. If CONFIG_NFCT_PINS_AS_GPIOS is not defined,
       two GPIOs (see Product Specification to see which ones) will be reserved for NFC and will not be available as
       normal GPIOs. */
#if defined (CONFIG_NFCT_PINS_AS_GPIOS)
        if ((NRF_UICR->NFCPINS & UICR_NFCPINS_PROTECT_Msk) == (UICR_NFCPINS_PROTECT_NFC << UICR_NFCPINS_PROTECT_Pos)){
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->NFCPINS &= ~UICR_NFCPINS_PROTECT_Msk;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NVIC_SystemReset();
        }
#endif

    /* Configure GPIO pads as pPin Reset pin if Pin Reset capabilities desired. If CONFIG_GPIO_AS_PINRESET is not
      defined, pin reset will not be available. One GPIO (see Product Specification to see which one) will then be
      reserved for PinReset and not available as normal GPIO. */
#if defined (CONFIG_GPIO_AS_PINRESET)
        if (((NRF_UICR->PSELRESET[0] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos)) ||
            ((NRF_UICR->PSELRESET[1] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos))){
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[0] = 18;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[1] = 18;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NVIC_SystemReset();
        }
#endif

    SystemCoreClockUpdate();

    // Start the LF oscilator according to the mbed configuration (over the nrf5x_lf_clk_helper.h file)
    NRF_CLOCK->LFCLKSRC             = (CLOCK_LFCLKSRC_SRC_TO_USE << CLOCK_LFCLKSRC_SRC_Pos);
    NRF_CLOCK->EVENTS_LFCLKSTARTED  = 0;
    NRF_CLOCK->TASKS_LFCLKSTART     = 1;

    // Wait for the external oscillator to start up.
    while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0) {
        // Do nothing.
    }

    /**
     * Mbed HAL specific code section.
     *
     * The ITM has to be initialized before the SoftDevice which weren't guaranteed using the normal API.
     */
#if defined (DEVICE_ITM)
        /* Enable SWO trace functionality */
        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Serial << CLOCK_TRACECONFIG_TRACEMUX_Pos;

        /* set SWO clock speed to 4 MHz */
        NRF_CLOCK->TRACECONFIG = (NRF_CLOCK->TRACECONFIG & ~CLOCK_TRACECONFIG_TRACEPORTSPEED_Msk) |
                                 (CLOCK_TRACECONFIG_TRACEPORTSPEED_4MHz << CLOCK_TRACECONFIG_TRACEPORTSPEED_Pos);

        /* set SWO pin */
        NRF_P0->PIN_CNF[18] = (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos) |
                              (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
                              (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);

        /* set prescaler */
        TPI->ACPR = 0;
#endif

}