~use forloop to remove ctz which is not portable~ keep ctz() since it is better for run time in isr
support ra2a1 pipe number scheme
fix ra2a1 ek led/button, but usb not enumerated probably bsp/clock setup thing.
Note to myself: while debugging, I notice sometimes somehow the _dcd seems to be clear accidentally, not sure what causes it. Maybe an memory overflow or something.
Describe the PR
Note to myself: while debugging, I notice sometimes somehow the _dcd seems to be clear accidentally, not sure what causes it. Maybe an memory overflow or something.