4 files changed, 52 insertions, 27 deletions
diff --git a/color.c b/color.c
index 967350f..9806979 100644
--- a/color.c
+++ b/color.c
@@ -1,9 +1,6 @@
 #include "color.h"
 #include <stdint.h>
 
-#define LED_RED (1U << 1)
-#define LED_BLUE (1U << 2)
-#define LED_GREEN (1U << 3)
 
 void set_color(uint8_t color) {
 	switch (color) {
@@ -16,6 +13,9 @@ void set_color(uint8_t color) {
 		case GREEN:
       GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3, 0x8);
 			break;
+		case YELLOW:
+      GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3, 0xA);
+			break;
 		case WHITE:
       GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3, 0xe);
 			break;
diff --git a/color.h b/color.h
index 77fe82a..1d1b0bc 100644
--- a/color.h
+++ b/color.h
@@ -1,6 +1,9 @@
 #include "tivaware.h"
 
 
+#define LED_RED (1U << 1)
+#define LED_BLUE (1U << 2)
+#define LED_GREEN (1U << 3)
 #define PORTF GPIO_PORTF_DATA_R
 #define INTIAL_COLOR WHITE
 #define RED 1
diff --git a/main.c b/main.c
index c076e22..7dbc47a 100644
--- a/main.c
+++ b/main.c
@@ -1,8 +1,37 @@
 #include "color.h"
-#include "systick.h"
 #include "stdio.h"
+#include <stdint.h>
 
-int cnt = 0;
+int cnt = 1;
+#define GREEN_PERIOD 80000000
+#define YELLOW_PERIOD 48000000
+#define RED_PERIOD 16000000
+uint8_t cur_color = GREEN;
+uint32_t period = GREEN_PERIOD;
+
+
+
+
+void Timer0_Handler() {
+  TimerIntClear(TIMER0_BASE, TIMER_BOTH);
+  switch(cur_color) {
+    case RED: 
+      cur_color = GREEN;
+      set_color(cur_color);
+      TimerLoadSet(TIMER0_BASE, TIMER_BOTH, GREEN_PERIOD);
+      break;
+    case YELLOW: 
+      cur_color = RED;
+      set_color(cur_color);
+      TimerLoadSet(TIMER0_BASE, TIMER_BOTH, RED_PERIOD);
+      break;
+    case GREEN: 
+      cur_color = YELLOW;
+      set_color(cur_color);
+      TimerLoadSet(TIMER0_BASE, TIMER_BOTH, YELLOW_PERIOD);
+      break;
+  }
+}
 
 void portFInit() {
   SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
@@ -13,34 +42,26 @@ void portFInit() {
   GPIOPadConfigSet (GPIO_PORTF_BASE, GPIO_PIN_0 | GPIO_PIN_4,
   GPIO_STRENGTH_2MA,GPIO_PIN_TYPE_STD_WPU);
 }
-
-void toggle_white() {
-  if((GPIO_PORTF_DATA_R & 0xe) == 0xe) {
-    reset_color();
-  } else {
-    set_color(WHITE);
-  }
-}
-
-void SysTick_Handler() {
-  cnt++;
-  if(cnt % 5 == 0) {
-    toggle_color(WHITE);
-  }
-}
-
-void toggle_interrupts() {
+void traffic_delay() {
   portFInit();
-  SysTickDisable();
-  SysTickPeriodSet(PERIOD);
-  SysTickIntEnable();
-  SysTickEnable();
+  reset_color();
+  SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);
+  while(!SysCtlPeripheralReady(SYSCTL_PERIPH_TIMER0)) {}
+  TimerDisable(TIMER0_BASE, TIMER_BOTH);
+  TimerConfigure(TIMER0_BASE, (TIMER_CFG_PERIODIC));
+  TimerLoadSet(TIMER0_BASE, TIMER_BOTH, period);
+  TimerIntUnregister(TIMER0_BASE, TIMER_BOTH);
+  TimerEnable(TIMER0_BASE, TIMER_BOTH);
+  set_color(GREEN);
+  TimerIntRegister(TIMER0_BASE, TIMER_BOTH, (*Timer0_Handler));
+  TimerIntEnable(TIMER0_BASE, TIMER_TIMA_TIMEOUT | TIMER_TIMB_TIMEOUT);
   while(1) {
 
   }
+
 }
 
 int main()
 {
-  toggle_interrupts();
+  traffic_delay();
 }
diff --git a/tivaware.h b/tivaware.h
index 3438c1a..ce3d029 100644
--- a/tivaware.h
+++ b/tivaware.h
@@ -6,6 +6,7 @@
 #include "../../ti/TivaWare_C_Series-2.2.0.295/driverlib/gpio.h"
 #include "../../ti/TivaWare_C_Series-2.2.0.295/driverlib/sysctl.h"
 #include "../../ti/TivaWare_C_Series-2.2.0.295/driverlib/systick.h"
+#include "../../ti/TivaWare_C_Series-2.2.0.295/driverlib/timer.h"
 
 #define RIGHT_SWITCH    !(GPIOPinRead(GPIO_PORTF_BASE, GPIO_PIN_0) != 0)
 #define LEFT_SWITCH     !(GPIOPinRead(GPIO_PORTF_BASE, GPIO_PIN_4) != 0)