diff --git a/firmware/Makefile b/firmware/Makefile
index f1ed677..09dbae4 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -5,7 +5,7 @@ CC = msp430-gcc -mmcu=cc430f6137 -Wall
 BSL = ../bin/cc430-bsl.py
 
 
-modules=main.o lcd.o lcdtext.o
+modules=main.o lcd.o lcdtext.o rtc.o
 
 all: goodwatch.hex
 
diff --git a/firmware/main.c b/firmware/main.c
index adde4b2..c0de6c2 100644
--- a/firmware/main.c
+++ b/firmware/main.c
@@ -11,9 +11,10 @@ int main(void) {
   WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
   
   lcd_init();
+  rtc_init();
 
   // Setup and enable WDT 1000ms, ACLK, interval timer
-  WDTCTL = WDT_ADLY_1000;
+  WDTCTL = WDT_ADLY_250;
   SFRIE1 |= WDTIE;
   
   __bis_SR_register(LPM0_bits + GIE);		// Enter LPM3 w/interrupt
@@ -22,5 +23,9 @@ int main(void) {
 
 // Watchdog Timer interrupt service routine, calls back to handler functions.
 void __attribute__ ((interrupt(WDT_VECTOR))) watchdog_timer (void) {
-  lcd_wdt();
+  //lcd_wdt();
+  //draw_time();
+
+  //Blink the colon faster than the RTC.
+  setcolon(3);
 }
diff --git a/firmware/rtc.c b/firmware/rtc.c
new file mode 100644
index 0000000..8a56e4b
--- /dev/null
+++ b/firmware/rtc.c
@@ -0,0 +1,86 @@
+/* RTC driver for the GoodWatch.
+ */
+
+#include <msp430.h>
+
+#include "rtc.h"
+#include "lcd.h"
+#include "lcdtext.h"
+
+
+
+static int h=17, m=9, s=0;
+
+//! Get the hour.
+int get_hour(){
+  return h%24;
+}
+//! Get the minute.
+int get_minute(){
+  return m%60;
+}
+//! Get the second.
+int get_second(){
+  return s%60;
+}
+
+//! Increase the clock by one second.
+void tick_clock(){
+  if(++s>60){
+    m++;
+    s-=60;
+  }
+  if(m>60){
+    h++;
+    m-=60;
+  }
+  if(h>24){
+    h-=24;
+  }
+}
+
+void draw_time(){
+  int hour=get_hour();
+  int min=get_minute();
+  int sec=get_second();
+  
+  lcd_zero();
+  lcd_digit(7,hour/10);
+  lcd_digit(6,hour%10);
+  setcolon(1);
+  lcd_digit(4,min/10);
+  lcd_digit(3,min%10);
+  //space
+  lcd_digit(1,sec/10);
+  lcd_digit(0,sec%10);
+}
+
+void rtc_init(){
+  // Setup RTC Timer
+  RTCCTL01 = RTCTEVIE + RTCSSEL_2 + RTCTEV_0; // Counter Mode, RTC1PS, 8-bit ovf
+                                            // overflow interrupt enable
+  RTCPS0CTL = RT0PSDIV_2;                   // ACLK, /8, start timer
+  RTCPS1CTL = RT1SSEL_2 + RT1PSDIV_3;       // out from RT0PS, /16, start timer
+
+  //__bis_SR_register(LPM3_bits + GIE);
+}
+
+void __attribute__ ((interrupt(RTC_VECTOR))) RTC_ISR (void){
+  //switch(__even_in_range(RTCIV,16))
+  switch(RTCIV&~1){
+    case 0: break;                          // No interrupts
+    case 2: break;                          // RTCRDYIFG
+    case 4:                                 // RTCEVIFG
+      tick_clock();
+      draw_time();
+      break;
+    case 6: break;                          // RTCAIFG
+    case 8: break;                          // RT0PSIFG
+    case 10: break;                         // RT1PSIFG
+    case 12: break;                         // Reserved
+    case 14: break;                         // Reserved
+    case 16: break;                         // Reserved
+    default: break;
+  }
+  
+}
diff --git a/firmware/rtc.h b/firmware/rtc.h
new file mode 100644
index 0000000..9a661f2
--- /dev/null
+++ b/firmware/rtc.h
@@ -0,0 +1,7 @@
+
+
+int get_hour();
+int get_minute();
+int get_second();
+
+void draw_time();