Diff: targets/TARGET_NUVOTON/TARGET_M451/device/system_M451Series.c

Revision:

149:156823d33999

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_NUVOTON/TARGET_M451/device/system_M451Series.c	Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,111 @@
+/******************************************************************************
+ * @file     system_M451Series.c
+ * @version  V0.10
+ * $Revision: 11 $
+ * $Date: 15/09/02 10:02a $
+ * @brief    CMSIS Cortex-M4 Core Peripheral Access Layer Source File for M451 Series MCU
+ *
+ * @note
+ * Copyright (C) 2013~2015 Nuvoton Technology Corp. All rights reserved.
+*****************************************************************************/
+
+#include "M451Series.h"
+
+
+/*----------------------------------------------------------------------------
+  DEFINES
+ *----------------------------------------------------------------------------*/
+
+
+/*----------------------------------------------------------------------------
+  Clock Variable definitions
+ *----------------------------------------------------------------------------*/
+uint32_t SystemCoreClock  = __SYSTEM_CLOCK;    /*!< System Clock Frequency (Core Clock)*/
+uint32_t CyclesPerUs      = (__HSI / 1000000); /* Cycles per micro second */
+uint32_t PllClock         = __HSI;             /*!< PLL Output Clock Frequency         */
+uint32_t gau32ClkSrcTbl[] = {__HXT, __LXT, 0, __LIRC, 0, 0, 0, __HIRC};
+
+/*----------------------------------------------------------------------------
+  Clock functions
+ *----------------------------------------------------------------------------*/
+void SystemCoreClockUpdate(void)             /* Get Core Clock Frequency      */
+{
+#if 1
+    uint32_t u32Freq, u32ClkSrc;
+    uint32_t u32HclkDiv;
+
+    /* Update PLL Clock */
+    PllClock = CLK_GetPLLClockFreq();
+
+    u32ClkSrc = CLK->CLKSEL0 & CLK_CLKSEL0_HCLKSEL_Msk;
+
+    if(u32ClkSrc == CLK_CLKSEL0_HCLKSEL_PLL)
+    {
+        /* Use PLL clock */
+        u32Freq = PllClock;
+    }
+    else
+    {
+        /* Use the clock sources directly */
+        u32Freq = gau32ClkSrcTbl[u32ClkSrc];
+    }
+
+    u32HclkDiv = (CLK->CLKDIV0 & CLK_CLKDIV0_HCLKDIV_Msk) + 1;
+
+    /* Update System Core Clock */
+    SystemCoreClock = u32Freq / u32HclkDiv;
+
+
+    //if(SystemCoreClock == 0)
+    //    __BKPT(0);
+
+    CyclesPerUs = (SystemCoreClock + 500000) / 1000000;
+#endif
+}
+
+/**
+ * Initialize the system
+ *
+ * @param  None
+ * @return None
+ *
+ * @brief  Setup the microcontroller system.
+ *         Initialize the System.
+ */
+void SystemInit(void)
+{
+    /* ToDo: add code to initialize the system
+             do not use global variables because this function is called before
+             reaching pre-main. RW section maybe overwritten afterwards.          */
+    
+    SYS_UnlockReg();
+    /* One-time POR18 */
+    if((SYS->PDID >> 12) == 0x945)
+    {
+        M32(GCR_BASE+0x14) |= BIT7;
+    }
+    /* Force to use INV type with HXT */
+    CLK->PWRCTL &= ~CLK_PWRCTL_HXTSELTYP_Msk;
+    SYS_LockReg();
+
+
+#if 0
+    // NOTE: C-runtime not initialized yet. Ensure no static memory (global variable) are accessed in this function.
+    nu_ebi_init();
+#endif
+
+    /* FPU settings ------------------------------------------------------------*/
+#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
+    SCB->CPACR |= ((3UL << 10 * 2) |               /* set CP10 Full Access */
+                   (3UL << 11 * 2));               /* set CP11 Full Access */
+#endif
+
+}
+
+#if 0
+void nu_ebi_init(void)
+{
+    // TO BE CONTINUED
+}
+#endif
+/*** (C) COPYRIGHT 2013~2015 Nuvoton Technology Corp. ***/