UART's Problem

Dear

I’m developing a home automation application with Beaglebone, for it I need to work with UART’s pins and It happens a strange problem.

I tried to work with UART’s using two ways, through USB host and UART2 both I can’t read what I’m receiving. I can only read through a minicom ternimal. I researched all websites as possible as could but without success. I didn’t find any serial library for arm - gcc neither.

For example,

For transmit a data I type : echo " teste" > /dev/ttyO2 or /dev/ttyUSB0 , It works

but for received;

cat /dev/ttyO2 or cat /dev/ttyUSB0

Nothing happens

For you understand better, follow my Youtube Video
http://www.youtube.com/watch?v=-2fcXWfLsgY

Can anybody help me with this situation.

Best regard’s

Mauricio.