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

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

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+                  /* Quick interactive demo running servo with Timer 1 */
+
+// ------- Preamble -------- //
+#include <avr/io.h>
+#include <util/delay.h>
+#include <avr/interrupt.h>
+
+#include "pinDefines.h"
+#include "USART.h"
+
+#define PULSE_MIN         1000         /* experiment with these values */
+#define PULSE_MAX         2000              /* to match your own servo */
+#define PULSE_MID         1500
+
+static inline uint16_t getNumber16(void);
+
+static inline void initTimer1Servo(void) {
+                   /* Set up Timer1 (16bit) to give a pulse every 20ms */
+                             /* Use Fast PWM mode, counter max in ICR1 */
+  TCCR1A |= (1 << WGM11);
+  TCCR1B |= (1 << WGM12) | (1 << WGM13);
+  TCCR1B |= (1 << CS10);  /* /1 prescaling -- counting in microseconds */
+  ICR1 = 20000;                                    /* TOP value = 20ms */
+  TCCR1A |= (1 << COM1A1);              /* Direct output on PB1 / OC1A */
+  DDRB |= (1 << PB1);                            /* set pin for output */
+}
+
+static inline void showOff(void) {
+  printString("Center\r\n");
+  OCR1A = PULSE_MID;
+  _delay_ms(1500);
+  printString("Clockwise Max\r\n");
+  OCR1A = PULSE_MIN;
+  _delay_ms(1500);
+  printString("Counterclockwise Max\r\n");
+  OCR1A = PULSE_MAX;
+  _delay_ms(1500);
+  printString("Center\r\n");
+  OCR1A = PULSE_MID;
+  _delay_ms(1500);
+}
+
+int main(void) {
+
+  // -------- Inits --------- //
+  uint16_t servoPulseLength;
+  OCR1A = PULSE_MID;            /* set it to middle position initially */
+  initTimer1Servo();
+  initUSART();
+  printString("\r\nWelcome to the Servo Demo\r\n");
+  showOff();
+
+  // ------ Event loop ------ //
+  while (1) {
+
+    printString("\r\nEnter a four-digit pulse length:\r\n");
+    servoPulseLength = getNumber16();
+
+    printString("On my way....\r\n");
+    OCR1A = servoPulseLength;
+    DDRB |= (1 << PB1);                        /* re-enable output pin */
+
+    _delay_ms(1000);
+    printString("Releasing...\r\n");
+    while (TCNT1 < 3000) {;
+    }                          /* delay until pulse part of cycle done */
+    DDRB &= ~(1 << PB1);                         /* disable output pin */
+
+  }                                                  /* End event loop */
+  return 0;                            /* This line is never reached */
+}
+
+static inline uint16_t getNumber16(void) {
+  // Gets a PWM value from the serial port.
+  // Reads in characters, turns them into a number
+  char thousands = '0';
+  char hundreds = '0';
+  char tens = '0';
+  char ones = '0';
+  char thisChar = '0';
+
+  do {
+    thousands = hundreds;                        /* shift numbers over */
+    hundreds = tens;
+    tens = ones;
+    ones = thisChar;
+    thisChar = receiveByte();                   /* get a new character */
+    transmitByte(thisChar);                                    /* echo */
+  } while (thisChar != '\r');
+
+  transmitByte('\n');                                       /* newline */
+  return (1000 * (thousands - '0') + 100 * (hundreds - '0') +
+          10 * (tens - '0') + ones - '0');
+}