Started following some tutorial on att85 usi. Downloaded example code from make avr book.

Make AVR Examples/Chapter11_Driving-Servo-Motors/servoSundial/servoSundial.c

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+                           /* Quasi-realtime-clock with servo sundial. */
+
+// ------- Includes -------- //
+#include "servoSundial.h"
+#include "_servoSerialHelpers.h"
+#include "_servoClockFunctions.h"
+
+// -------- Global Variables --------- //
+volatile uint16_t ticks;
+volatile uint8_t hours = 15;                 /* arbitrary default time */
+volatile uint8_t minutes = 42;
+volatile uint8_t seconds = 57;
+
+ISR(TIMER0_OVF_vect) {
+     /* This is going off very frequently, so we should make it speedy */
+  ticks++;
+}
+
+// -------- Functions --------- //
+// Servo setup and utility functions
+void initTimer1_Servo(void) {
+                   /* Set up Timer1 (16bit) to give a pulse every 20ms */
+  TCCR1A |= (1 << WGM11);                       /* Using Fast PWM mode */
+  TCCR1B |= (1 << WGM12);                       /* counter max in ICR1 */
+  TCCR1B |= (1 << WGM13);
+  TCCR1B |= (1 << CS11);         /* /8 prescaling -- microsecond steps */
+  TCCR1A |= (1 << COM1A1);       /* set output on PB1 / OC1A for servo */
+  ICR1 = 20000;                                    /* TOP value = 20ms */
+}
+
+void enableServo(void) {
+  while (TCNT1 < PULSE_OVER) {;
+  }                            /* delay until pulse part of cycle done */
+  SERVO_DDR |= (1 << SERVO);                    /* enable servo pulses */
+}
+
+void disableServo(void) {
+  while (TCNT1 < PULSE_OVER) {;
+  }                            /* delay until pulse part of cycle done */
+  SERVO_DDR &= ~(1 << SERVO);                  /* disable servo pulses */
+}
+
+void setServoPosition(void) {
+  uint32_t elapsedMinutes;
+/* using 32 bits b/c elapsedMinutes * PULSE_RANGE will overflow 16 bits */
+
+
+
+  elapsedMinutes = (hours - START_TIME) * 60 + minutes;
+  OCR1A = PULSE_MIN + elapsedMinutes * PULSE_RANGE / (HOURS_RANGE * 60);
+  enableServo();
+}
+
+int main(void) {
+
+  // -------- Inits --------- //
+  clock_prescale_set(clock_div_1);                  /* CPU clock 8 MHz */
+  initUSART();
+  printString("\r\nWelcome to the Servo Sundial.\r\n");
+  printString("Type S to set time.\r\n");
+
+  initTimer0_Clock();
+  initTimer1_Servo();
+  sei();                                   /* set enable interrupt bit */
+  LED_DDR |= (1 << LED0);                             /* blinky output */
+  LASER_DDR |= (1 << LASER);                    /* enable laser output */
+
+  // ------ Event loop ------ //
+  while (1) {
+
+                                                 /* Poll clock routine */
+    if (ticks == OVERFLOWS_PER_SECOND) {
+      ticks = 0;
+      everySecond();
+    }
+
+    pollSerial();
+
+  }                                                  /* End event loop */
+  return 0;                            /* This line is never reached */
+}