Pulse oats in food processor 5 to 6 times until ground.
Combine ground oats, wheat flour, and next 5 ingredients in a large bowl.
Whisk together buttermilk, eggs, and butter; stir into oat mixture.
Pour 1/4 cup batter for each pancake onto a hot griddle coated with cooking spray. Cook pancakes until tops are covered with bubbles and edges look cooked; turn and cook other side.