dfu permission issues

README.md

@@ -68,6 +68,13 @@ cargo install flip-link # needed for building
 cargo install cargo-dfu # needed for flashing
 ```
 
+Finally, if you're on Linux, you may need to give yourself permission to write to the board.
+
+```bash
+sudo cp udev.rules /etc/udev/rules.d/99-dfu-stm32.rules
+sudo udevadm control --reload-rules && sudo udevadm trigger
+```
+
 ### Board setup
 1. Connect the board to your computer via USB
 2. Hold down the `flash` button

udev.rules

+SUBSYSTEMS == "usb" ATTRS{idVendor}=="0483" ATTRS{idProduct}=="df11" MODE:="0666"