Diff: tick.c

Revision:

18:207dd1474cd9

Parent:

17:927fc1eceb9d

Child:

19:e537bacd1478

--- a/tick.c	Thu Jan 11 17:39:36 2018 +0000
+++ b/tick.c	Tue Jan 16 17:38:12 2018 +0000
@@ -1,10 +1,12 @@
+#include <stdint.h>
+#include <stdbool.h>
+
 #include "peripherals.h"
 #include  "rtc.h"
 #include "time.h"
 #include "tick.h"
-
-#define TRUE  1
-#define FALSE 0
+#include "led.h"
+#include "log.h"
 
 #define ONE_BILLION 1000000000
 
@@ -12,16 +14,14 @@
 static volatile int64_t nsFreqCount;
 static volatile int64_t nsTimeCount;
 
-static int nsCountIsSet = FALSE;
-int  TickIsSet() { return nsCountIsSet; }
+static bool nsCountIsSet = false;
+bool  TickIsSet() { return nsCountIsSet; }
 void TickSet(int64_t extClock)
 {
-    nsTickCount   = 0;
-    nsFreqCount   = 0;
-    nsTimeCount   = extClock;
-    LPC_TIM1->TCR = 2; // 21.6.2 Timer Control Register - Reset  TC and PC.
-    LPC_TIM1->TCR = 1; // 21.6.2 Timer Control Register - Enable TC and PC.
-    nsCountIsSet = TRUE;
+    nsTickCount  = 0;
+    nsFreqCount  = 0;
+    nsTimeCount  = extClock - LPC_TIM1->TC;
+    nsCountIsSet = true;
 }
 
 static volatile int32_t slew = 0; //ns     - up to +/- 2.147s of slew
@@ -33,41 +33,34 @@
 void    TickSetPpb (int32_t value) { ppb  = value; LPC_RTC->GPREG0 = ppb; }
 void    TickAddPpb (int32_t value) { ppb += value; LPC_RTC->GPREG0 = ppb; }
 
-#define CLOCK_TIC 0
-#define CLOCK_INT 1
-#define CLOCK_ABS 2
-
-__irq void TickHandler(void)
-{//Checked the number of counts and this routine takes 46 counts or about 0.5us
-
-    //Reset the timer interrupt
-    LPC_TIM1->IR |= 1;
-    
-    //reset the tick timer
-    LPC_TIM1->TCR = 2; // 21.6.2 Timer Control Register - Reset  TC and PC.
-    LPC_TIM1->TCR = 1; // 21.6.2 Timer Control Register - Enable TC and PC
-    
-    //Calculate the new counts
-    nsTickCount += ONE_BILLION;
-    nsFreqCount += ppb;
-    nsTimeCount += slew;
-    
-    //Feedback the amount slewed
-    slew = 0;
+static uint32_t lastCall = 0;
+void TickMain()
+{
+    uint32_t sinceLastCall = LPC_TIM1->TC - lastCall;
+    if (sinceLastCall > TICK_COUNT_PER_SECOND)
+    { 
+        __disable_irq();
+           lastCall += TICK_COUNT_PER_SECOND;
+        nsTickCount += ONE_BILLION;
+        nsFreqCount += ppb;
+        nsTimeCount += slew;
+               slew  = 0;
+        __enable_irq();
+    }
 }
-static volatile int64_t nsTickSnapshot;
-static volatile int64_t nsFreqSnapshot;
-static volatile int64_t nsTimeSnapshot;
-static volatile int32_t  timerSnapshot;
+static volatile  int64_t nsTickSnapshot;
+static volatile  int64_t nsFreqSnapshot;
+static volatile  int64_t nsTimeSnapshot;
+static volatile uint32_t  timerSnapshot;
 
 void TickSaveSnapshotI()
 {
-     timerSnapshot = LPC_TIM1->TC;
+     timerSnapshot = LPC_TIM1->TC - lastCall;
     nsTickSnapshot = nsTickCount;
     nsFreqSnapshot = nsFreqCount;
     nsTimeSnapshot = nsTimeCount;
 }
-static void makeTimesFromCounts(int32_t timerCount, int64_t tickNs, int64_t freqNs, int64_t timeNs, int64_t* pNsInt, int64_t* pNsAbs)
+static void makeTimesFromCounts(uint32_t timerCount, int64_t tickNs, int64_t freqNs, int64_t timeNs, int64_t* pNsInt, int64_t* pNsAbs)
 {
     int64_t   fraction = timerCount;
               fraction <<= 32;
@@ -94,13 +87,13 @@
 }
 void TickGetTimes(int64_t* pNsInt, int64_t* pNsAbs)
 {
-    int32_t timerCount;
-    int64_t tickNs;
-    int64_t freqNs;
-    int64_t timeNs;
+    uint32_t timerCount;
+     int64_t tickNs;
+     int64_t freqNs;
+     int64_t timeNs;
     
     __disable_irq();
-        timerCount = LPC_TIM1->TC;
+        timerCount = LPC_TIM1->TC - lastCall;
          tickNs    = nsTickCount;
          freqNs    = nsFreqCount;
          timeNs    = nsTimeCount;
@@ -117,36 +110,19 @@
     
     ppb  = LPC_RTC->GPREG0; //This is saved each time Tickppb is updated
     slew = 0;
-    nsCountIsSet = FALSE;
+    nsCountIsSet = false;
     
-    LPC_SC->PCLKSEL0 &= ~0x20; //  4.7.3 Peripheral Clock Selection - PCLK_peripheral PCLK_TIMER1 01xxxx = CCLK - reset bit 5
-    LPC_SC->PCLKSEL0 |=  0x10; //                                                                                   set bit 4
     LPC_SC->PCONP    |=     4; //  4.8.9 Power Control for Peripherals register - Timer1 Power On
     LPC_TIM1->TCR     =     2; // 21.6.2 Timer Control Register - Reset TC and PC.
     LPC_TIM1->CTCR    =     0; // 21.6.3 Count Control Register - Timer mode
     LPC_TIM1->PR      =     0; // 21.6.5 Prescale register      - Don't prescale 96MHz clock (divide by PR+1).
-    LPC_TIM1->MR0     = TICK_COUNT_PER_SECOND; // 21.6.7 Match Register 0       - Match count
-    LPC_TIM1->MCR     =     1; // 21.6.8 Match Control Register - interrupt on match
+    LPC_TIM1->MCR     =     0; // 21.6.8 Match Control Register - no interrupt or reset
     LPC_TIM1->TCR     =     1; // 21.6.2 Timer Control Register - Enable TC and PC
-    
-    NVIC->ISER[0] |= 0x04;     //  6.5.1 bit2 == Interrupt set enable for timer 1.
 }
-int32_t TickElapsed(int32_t* pLastTime)
+uint32_t TickElapsed(uint32_t* pLastTime)
 {
-    int32_t thisTime = LPC_TIM1->TC;
-    
-    if (thisTime < *pLastTime) *pLastTime -= TICK_COUNT_PER_SECOND; //lastCount could be 96 000 002 and thisTime could be 00 000 100 which should give 98
-    int32_t elapsed = thisTime - *pLastTime;
-    
+    uint32_t thisTime = LPC_TIM1->TC;
+    uint32_t elapsed = thisTime - *pLastTime;    
     *pLastTime = thisTime;
     return elapsed;
 }
-int Ticked(int32_t* pLastTime)
-{
-    int thisTime = LPC_TIM1->TC;
-    
-    int ticked = thisTime < *pLastTime;
-    
-    *pLastTime = thisTime;
-    return ticked;
-}