Diff: Watchdog.cpp

Revision:

5:ea5595e2698b

Parent:

3:5959d3d35221

Child:

6:40f189c7795b

--- a/Watchdog.cpp	Sat Oct 11 17:28:07 2014 +0000
+++ b/Watchdog.cpp	Mon Mar 02 21:33:58 2015 +0000
@@ -12,29 +12,116 @@
 ///     this copyright statement remains in the source file.
 /// @author David Smart
 ///
+/// @note Copyright © 2015 by NBRemond, all rights reserved.
+///     This software may be used to derive new software, as long as
+///     this copyright statement remains in the source file.
+///
+///     Added support for STM32 Nucleo platforms
+///
+/// @author Bernaérd Remond
+///
+
+//#define LPC
+#define ST_NUCLEO
+
+
 #include "mbed.h"
 #include "Watchdog.h"
 
 
 /// Watchdog gets instantiated at the module level
 Watchdog::Watchdog() {
+#ifdef LPC    
     wdreset = (LPC_WDT->WDMOD >> 2) & 1;    // capture the cause of the previous reset
+#endif
+#ifdef ST_NUCLEO
+    // capture the cause of the previous reset
+    /* Check if the system has resumed from IWDG reset */
+/*
+    if (__HAL_RCC_GET_FLAG(RCC_FLAG_IWDGRST)) {
+        wdreset = true;
+    }
+    else {
+        wdreset = false; 
+    }
+*/        
+        wdreset = false; 
+#endif
+
 }
 
 /// Load timeout value in watchdog timer and enable
-void Watchdog::Configure(float s) {
+void Watchdog::Configure(float timeout) {
+#ifdef LPC    
     LPC_WDT->WDCLKSEL = 0x1;                // Set CLK src to PCLK
     uint32_t clk = SystemCoreClock / 16;    // WD has a fixed /4 prescaler, PCLK default is /4
-    LPC_WDT->WDTC = (uint32_t)(s * (float)clk);
+    LPC_WDT->WDTC = (uint32_t)(timeout * (float)clk);
     LPC_WDT->WDMOD = 0x3;                   // Enabled and Reset
+#endif   
+#ifdef ST_NUCLEO
+    // see http://embedded-lab.com/blog/?p=9662    
+    #define LsiFreq (45000)
+    
+    uint16_t PrescalerCode;
+    uint16_t Prescaler;
+    uint16_t ReloadValue;
+    float Calculated_timeout;
+    
+    if ((timeout * (LsiFreq/4)) < 0x7FF) {
+        PrescalerCode = IWDG_PRESCALER_4;
+        Prescaler = 4;
+    }
+    else if ((timeout * (LsiFreq/8)) < 0xFF0) {
+        PrescalerCode = IWDG_PRESCALER_8;
+        Prescaler = 8;
+    }
+    else if ((timeout * (LsiFreq/16)) < 0xFF0) {
+        PrescalerCode = IWDG_PRESCALER_16;
+        Prescaler = 16;
+    }
+    else if ((timeout * (LsiFreq/32)) < 0xFF0) {
+        PrescalerCode = IWDG_PRESCALER_32;
+        Prescaler = 32;
+    }
+    else if ((timeout * (LsiFreq/64)) < 0xFF0) {
+        PrescalerCode = IWDG_PRESCALER_64;
+        Prescaler = 64;
+    }
+    else if ((timeout * (LsiFreq/128)) < 0xFF0) {
+        PrescalerCode = IWDG_PRESCALER_128;
+        Prescaler = 128;
+    }
+    else {
+        PrescalerCode = IWDG_PRESCALER_256;
+        Prescaler = 256;
+    }
+    
+    // specifies the IWDG Reload value. This parameter must be a number between 0 and 0x0FFF.
+    ReloadValue = (uint32_t)(timeout * (LsiFreq/Prescaler));
+    
+    Calculated_timeout = ((float)(Prescaler * ReloadValue)) / LsiFreq;
+    printf("WATCHDOG set with prescaler:%d reload value: 0x%X - timeout:%f\n",Prescaler, ReloadValue, Calculated_timeout);
+    
+    IWDG->KR = 0x5555; //Disable write protection of IWDG registers      
+    IWDG->PR = PrescalerCode;      //Set PR value      
+    IWDG->RLR = ReloadValue;      //Set RLR value      
+    IWDG->KR = 0xAAAA;    //Reload IWDG      
+    IWDG->KR = 0xCCCC;    //Start IWDG - See more at: http://embedded-lab.com/blog/?p=9662#sthash.6VNxVSn0.dpuf       
+#endif
+ 
     Service();
 }
 
 /// "Service", "kick" or "feed" the dog - reset the watchdog timer
 /// by writing this required bit pattern
 void Watchdog::Service() {
+#ifdef LPC    
     LPC_WDT->WDFEED = 0xAA;
     LPC_WDT->WDFEED = 0x55;
+#endif    
+#ifdef ST_NUCLEO
+    IWDG->KR = 0xAAAA;         //Reload IWDG - See more at: http://embedded-lab.com/blog/?p=9662#sthash.6VNxVSn0.dpuf
+#endif
 }
 
 /// get the flag to indicate if the watchdog causes the reset