I was listening to a demo of some software when someone
needed to upload a file from their computer to an attached radio
and they used alt + p. This gives you two alternatives, r and w
which is easy enough to follow so far except that I get that
unceremonious dumpout you get when you hit the wrong button and
the effect is the same as typing Escape. You just go back to
whatever was going on before typing alt + p.