void SystemInit(void)
{
#if defined(TARGET_NRF_32MHZ_XTAL)
/* For 32MHz HFCLK XTAL such as Taiyo Yuden
Physically, tiny footprint XTAL oscillate higher freq. To make BLE modules smaller, some modules
are using 32MHz XTAL.
This code wriging the value 0xFFFFFF00 to the UICR (User Information Configuration Register)
at address 0x10001008, to make nRF51 works with 32MHz system clock. This register will be overwritten
by SoftDevice to 0xFFFFFFFF, the default value. Each hex files built with mbed classic online compiler
contain SoftDevice, so that, this code run once just after the hex file will be flashed onto nRF51.
After changing the value, nRF51 need to reboot. */
if (*(uint32_t *)0x10001008 == 0xFFFFFFFF)
{
NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
*(uint32_t *)0x10001008 = 0xFFFFFF00;
NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
NVIC_SystemReset();
while (true){}
}
#endif
/* If desired, switch off the unused RAM to lower consumption by the use of RAMON register.
It can also be done in the application main() function. */
/* Prepare the peripherals for use as indicated by the PAN 26 "System: Manual setup is required
to enable the use of peripherals" found at Product Anomaly document for your device found at
https://www.nordicsemi.com/. The side effect of executing these instructions in the devices
that do not need it is that the new peripherals in the second generation devices (LPCOMP for
example) will not be available. */
if (is_manual_peripheral_setup_needed())
{
*(uint32_t volatile *)0x40000504 = 0xC007FFDF;
*(uint32_t volatile *)0x40006C18 = 0x00008000;
}
/* Disable PROTENSET registers under debug, as indicated by PAN 59 "MPU: Reset value of DISABLEINDEBUG
register is incorrect" found at Product Anomaly document four your device found at
https://www.nordicsemi.com/. There is no side effect of using these instruction if not needed. */
if (is_disabled_in_debug_needed())
{
NRF_MPU->DISABLEINDEBUG = MPU_DISABLEINDEBUG_DISABLEINDEBUG_Disabled << MPU_DISABLEINDEBUG_DISABLEINDEBUG_Pos;
}
// Start the external 32khz crystal oscillator.
init_clock();
}
void SystemInit(void)
{
/* If desired, switch off the unused RAM to lower consumption by the use of RAMON register.
It can also be done in the application main() function. */
/* Prepare the peripherals for use as indicated by the PAN 26 "System: Manual setup is required
to enable the use of peripherals" found at Product Anomaly document for your device found at
https://www.nordicsemi.com/. The side effect of executing these instructions in the devices
that do not need it is that the new peripherals in the second generation devices (LPCOMP for
example) will not be available. */
if (is_manual_peripheral_setup_needed())
{
*(uint32_t volatile *)0x40000504 = 0xC007FFDF;
*(uint32_t volatile *)0x40006C18 = 0x00008000;
}
/* Disable PROTENSET registers under debug, as indicated by PAN 59 "MPU: Reset value of DISABLEINDEBUG
register is incorrect" found at Product Anomaly document four your device found at
https://www.nordicsemi.com/. There is no side effect of using these instruction if not needed. */
if (is_disabled_in_debug_needed())
{
NRF_MPU->DISABLEINDEBUG = MPU_DISABLEINDEBUG_DISABLEINDEBUG_Disabled << MPU_DISABLEINDEBUG_DISABLEINDEBUG_Pos;
}
// Start the external 32khz crystal oscillator.
#if defined(TARGET_DELTA_DFCM_NNN40) || defined(TARGET_HRM1017)
NRF_CLOCK->LFCLKSRC = (CLOCK_LFCLKSRC_SRC_RC << CLOCK_LFCLKSRC_SRC_Pos);
#else
NRF_CLOCK->LFCLKSRC = (CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos);
#endif
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.
}
}
void SystemInit(void)
{
/* If desired, switch off the unused RAM to lower consumption by the use of RAMON register.
It can also be done in the application main() function. */
/* Prepare the peripherals for use as indicated by the PAN 26 "System: Manual setup is required
to enable the use of peripherals" found at Product Anomaly document for your device found at
https://www.nordicsemi.com/. The side effect of executing these instructions in the devices
that do not need it is that the new peripherals in the second generation devices (LPCOMP for
example) will not be available. */
if (is_manual_peripheral_setup_needed())
{
*(uint32_t volatile *)0x40000504 = 0xC007FFDF;
*(uint32_t volatile *)0x40006C18 = 0x00008000;
}
/* Disable PROTENSET registers under debug, as indicated by PAN 59 "MPU: Reset value of DISABLEINDEBUG
register is incorrect" found at Product Anomaly document four your device found at
https://www.nordicsemi.com/. There is no side effect of using these instruction if not needed. */
if (is_disabled_in_debug_needed())
{
NRF_MPU->DISABLEINDEBUG = MPU_DISABLEINDEBUG_DISABLEINDEBUG_Disabled << MPU_DISABLEINDEBUG_DISABLEINDEBUG_Pos;
}
}
