Feel free to swap in frozen berries for the fresh ones, just don't thaw them before you bake the crisp.
Heat oven to 350 degrees F.
In large bowl, mix together blueberries, 1/2 cup light-brown sugar, flour, orange juice and zest. Place into a 6- to 8-cup baking dish. Evenly scatter raspberries over the top.
In another large bowl, whisk together flour, brown sugar and cinnamon. Cut in butter until crumbly. Stir in oats and pecans.
Sprinkle topping evenly over berry filling. Bake at 350 degrees F for 55 minutes, until bubbly. Allow to cool 15 minutes before serving.