/* carry out clock initialization sequence */ static void nortos_clk_setup(void) { // Setup DIVN if (dg_configEXT_CRYSTAL_FREQ == EXT_CRYSTAL_IS_16M) { hw_cpm_set_divn(false); // External crystal is 16MHz } else { hw_cpm_set_divn(true); // External crystal is 32MHz } hw_cpm_enable_rc32k(); hw_cpm_lp_set_rc32k(); NVIC_ClearPendingIRQ(XTAL16RDY_IRQn); nortos_xtal16m_settled = false; NVIC_EnableIRQ(XTAL16RDY_IRQn); // Activate XTAL16 Ready IRQ hw_cpm_set_xtal16m_settling_time(dg_configXTAL16_SETTLE_TIME_RC32K); hw_cpm_enable_xtal16m(); // Enable XTAL16M hw_watchdog_unfreeze(); // Start watchdog while (!hw_cpm_is_xtal16m_started()); // Block until XTAL16M starts /* Wait for XTAL16M to settle */ while (!nortos_xtal16m_settled); hw_watchdog_freeze(); // Stop watchdog hw_cpm_set_sysclk(SYS_CLK_IS_XTAL16M); }
static void ClkSet(sys_clk_t clock) { switch (clock) { case sysclk_XTAL16M: if (!hw_cpm_check_xtal16m_status()) // XTAL16M disabled { hw_cpm_enable_xtal16m(); // Enable XTAL16M } hw_cpm_set_sysclk(SYS_CLK_IS_XTAL16M); // Set XTAL16 as sys_clk hw_watchdog_unfreeze(); // Start watchdog while (!hw_cpm_is_xtal16m_started()); // Block until XTAL16M starts hw_qspi_set_div(HW_QSPI_DIV_1); hw_watchdog_freeze(); // Stop watchdog hw_cpm_set_hclk_div(0); hw_cpm_set_pclk_div(0); break; case sysclk_PLL48: if (hw_cpm_is_pll_locked() == 0) { hw_watchdog_unfreeze(); // Start watchdog hw_cpm_pll_sys_on(); // Turn on PLL hw_watchdog_freeze(); // Stop watchdog } hw_cpm_enable_pll_divider(); // Enable divider (div by 2) hw_qspi_set_div(HW_QSPI_DIV_1); hw_cpm_set_sysclk(SYS_CLK_IS_PLL); hw_cpm_set_hclk_div(0); hw_cpm_set_pclk_div(0); break; case sysclk_PLL96: if (hw_cpm_is_pll_locked() == 0) { hw_watchdog_unfreeze(); // Start watchdog hw_cpm_pll_sys_on(); // Turn on PLL hw_watchdog_freeze(); // Stop watchdog } hw_cpm_disable_pll_divider(); // Disable divider (div by 1) hw_qspi_set_div(HW_QSPI_DIV_2); hw_cpm_set_sysclk(SYS_CLK_IS_PLL); hw_cpm_set_hclk_div(0); hw_cpm_set_pclk_div(0); break; default: break; } }
void ClkInit(void) { NVIC_ClearPendingIRQ(XTAL16RDY_IRQn); NVIC_EnableIRQ(XTAL16RDY_IRQn); // Activate XTAL16 Ready IRQ hw_cpm_set_divn(false); // External crystal is 16MHz hw_cpm_enable_rc32k(); hw_cpm_lp_set_rc32k(); hw_cpm_set_xtal16m_settling_time(dg_configXTAL16_SETTLE_TIME_RC32K); hw_cpm_enable_xtal16m(); // Enable XTAL16M hw_cpm_configure_xtal32k_pins(); // Configure XTAL32K pins hw_cpm_configure_xtal32k(); // Configure XTAL32K hw_cpm_enable_xtal32k(); // Enable XTAL32K hw_watchdog_unfreeze(); // Start watchdog while (!hw_cpm_is_xtal16m_started()); // Block until XTAL16M starts hw_watchdog_freeze(); // Stop watchdog hw_cpm_set_recharge_period((uint16_t)dg_configSET_RECHARGE_PERIOD); hw_cpm_set_sysclk(SYS_CLK_IS_XTAL16M); hw_cpm_set_hclk_div(0); hw_cpm_set_pclk_div(0); hw_otpc_init(); hw_otpc_set_speed(HW_OTPC_SYS_CLK_FREQ_16); }