Diff: main.cpp

Revision:

1:c0b9e466e9e5

Parent:

0:93e3779ebc48

--- a/main.cpp	Sun Apr 09 23:38:25 2017 +0000
+++ b/main.cpp	Mon Apr 10 11:10:26 2017 +0000
@@ -1,23 +1,34 @@
+// k64 wdog  using 1khz LPO (10% accuracy)
 #include "mbed.h"
 
 #define PRREG(z) printf(#z" 0x%x\n",z)
 Timer tmr;
 
-void wdog_init() {
+void wdog_init(uint32_t ms) {
     __disable_irq();
     WDOG->UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xC520); /* Key 1 */
     WDOG->UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xD928); /* Key 2 */
     __NOP();
     __NOP();
 
-    WDOG_TOVALL = (4000); // The next 2 lines sets the time-out value. This is the value that the watchdog timer compare itself to.
-    WDOG_TOVALH = 0;
+    WDOG_TOVALL = (uint16_t)(ms & 0xffff); //  sets the time-out value
+    WDOG_TOVALH = (uint16_t)((ms>>16) & 0xffff);
     WDOG_STCTRLH = (WDOG_STCTRLH_ALLOWUPDATE_MASK | WDOG_STCTRLH_WDOGEN_MASK | WDOG_STCTRLH_WAITEN_MASK | WDOG_STCTRLH_STOPEN_MASK); // Enable WDG
     WDOG_PRESC = 0; // prescaler 
     __enable_irq();
 }
 
-void kick() {
+void wdog_disable() {
+    __disable_irq();
+    WDOG->UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xC520); /* Key 1 */
+    WDOG->UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xD928); /* Key 2 */
+    __NOP();
+    __NOP();
+    WDOG_STCTRLH = WDOG_STCTRLH_ALLOWUPDATE_MASK; 
+    __enable_irq();
+}
+
+void wdog_kick() {
      __disable_irq();
     WDOG_REFRESH = 0xA602;
     WDOG_REFRESH = 0xB480;
@@ -29,23 +40,25 @@
     fbus = SystemCoreClock / (((SIM->CLKDIV1 & SIM_CLKDIV1_OUTDIV2_MASK) >> SIM_CLKDIV1_OUTDIV2_SHIFT) + 1);
     flashbus = SystemCoreClock / (((SIM->CLKDIV1 & SIM_CLKDIV1_OUTDIV4_MASK) >> SIM_CLKDIV1_OUTDIV4_SHIFT) + 1);
     printf("\nSystemCoreClock %d fbus %d flash %d %s %s\n",SystemCoreClock,fbus,flashbus,__TIME__,__DATE__);
-    PRREG(WDOG->STCTRLH);
-    PRREG(WDOG->PRESC);
-    PRREG(WDOG->TOVALL);
-    PRREG(WDOG->TOVALH);
-    PRREG(WDOG->RSTCNT);
-    wdog_init();
+    PRREG(RCM_SRS0);   // reset reason
+    PRREG(RCM_SRS1);
     PRREG(WDOG->STCTRLH);
     PRREG(WDOG->PRESC);
     PRREG(WDOG->TOVALL);
     PRREG(WDOG->TOVALH);
     PRREG(WDOG->RSTCNT);
+    wdog_init(4000);            // 4 sec timeout
+    PRREG(WDOG->STCTRLH);
+    PRREG(WDOG->PRESC);
+    PRREG(WDOG->TOVALL);
+    PRREG(WDOG->TOVALH);
+
     wait_ms(100);
-    kick();
-    for (i=1;i<=3; i++) {
+    wdog_kick();
+    for (i=1;i<=5; i++) {
         printf("running %d\n",i);
         wait(1.0);
-        kick();
+        wdog_kick();
     }
     printf("long wait reset\n");
     wait(5.0);