FIX: chap 1 - fixed at least two points but I don't know which one
actually took effect.

on both minicom and cu, I can see hellos from H8.

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
update README

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>