I use Mr. Clean Magic Eraser on my awning. Make the Eraser wet, but not dripping and simply wipe a small section (don't scrub, just wipe). Follow up with a dry towel. Rinse the Eraser and do the next small section. Repeat until the entire awning is done. Not only will it marvelously remove everything black, and bugs, and gunk and stains, it leaves a coating on the awning that prevents mold from coming back. Don't rinse the awning with clean water after wiping. Just wipe it dry. Use the Eraser to get the black off. You will need to wash your awning only 1 time a year, except for bugs that get rolled up inside sometimes, or leaves that fall on the top.
If you can reach the top, do the same with the top. It will not get the black mold any more for several months. When you notice a few spots, do it again. Like I said, I do mine once a year, in the Spring, first time we use the camper and it stays looking good all summer. There's something in the Mr. Clean that just simply stops mold from coming back.
Repeat, do not scrub with the Erase. Wipe with it and then follow up drying with a dry towel. Works wonderful!