Place a rack on the middle rung of the oven and preheat the oven to 350ºF.
Peel, quarter, and core the pears. Halve each wedge and slice crosswise into small chunks. Spread the pear pieces and cranberries evenly in a 9- by 13-inch baking pan. Sprinkle ½ cup sugar over the fruit and gently mix to combine.
In a stand mixer with the paddle attachment, mix the remaining 1½ cups sugar with the flours and salt on low speed. While the mixer is running, gradually add the butter and continue to mix until a coarse crumble forms. Spread the crumble evenly over the fruit, gently pressing it into the fruit (expect a thick layer covering the fruit).
Bake in the middle of the oven for 50 minutes or until the cranberry juices are bubbling and the topping is golden brown.