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

Make AVR Examples/Chapter15_Advanced-Motors/hBridgeWorkout/hBridgeWorkout.c

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+// Simple demo of an h-bridge
+
+// ------- Preamble -------- //
+#include <avr/io.h>
+#include <util/delay.h>
+#include <avr/interrupt.h>
+#include "pinDefines.h"
+
+static inline void setBridgeState(uint8_t bridgeA, uint8_t bridgeB) {
+  /* Utility function that lights LEDs when it energizes a bridge side */
+  if (bridgeA) {
+    PORTD |= (1 << PD6);
+    LED_PORT |= (1 << LED0);
+  }
+  else {
+    PORTD &= ~(1 << PD6);
+    LED_PORT &= ~(1 << LED0);
+  }
+  if (bridgeB) {
+    PORTD |= (1 << PD5);
+    LED_PORT |= (1 << LED1);
+  }
+  else {
+    PORTD &= ~(1 << PD5);
+    LED_PORT &= ~(1 << LED1);
+  }
+}
+
+
+int main(void) {
+  // -------- Inits --------- //
+
+  DDRD |= (1 << PD6);               /* now hooked up to bridge, input1 */
+  DDRD |= (1 << PD5);               /* now hooked up to bridge, input2 */
+  LED_DDR |= (1 << LED0);
+  LED_DDR |= (1 << LED1);
+
+  // ------ Event loop ------ //
+  while (1) {
+
+    setBridgeState(1, 0);                                 /* "forward" */
+    _delay_ms(2000);
+
+    setBridgeState(0, 0);                      /* both low stops motor */
+    _delay_ms(2000);
+
+    setBridgeState(0, 1);                                 /* "reverse" */
+    _delay_ms(2000);
+
+    setBridgeState(1, 1);                /* both high also stops motor */
+    _delay_ms(2000);
+
+    // For extra-quick braking, energize the motor backwards
+    setBridgeState(1, 0);
+    _delay_ms(2000);
+    setBridgeState(0, 1);
+    _delay_ms(75);              /* tune this time to match your system */
+    setBridgeState(0, 0);
+    _delay_ms(2000);
+
+  }                                                  /* End event loop */
+  return 0;
+}