Using UART


I try to use the UARTS 1,2,4.
I set up an own device tree and have the files “/dev/ttyO1”
When I send “echo hello > /dev/ttyO1” I get no information out of my cape.

How can I check if the pins are correct in UART mode?

Thank you!

btw: I miss also the path: “/sys/kernel/debug/omap_mux/”

I found some help in the internet, but all are using this path, what I doesn´t has.
BBB is brand new.

You can use one of the overlays here to set the different UARTS:

A good way to test if it is working is to place a wire between pins Tx and Rx.
You can use minicom

sudo minicom -b 9600 -D /dev/ttyO1

and check that you can see what you are writing. This means the feedback is working.

If you type

echo “hello” > /dev/ttyO1

while having minicom open you should be able to see “hello” printed on the minicom screen.


Many thanks for your answer!

I also found that the UART DeviceTree are already available.

I have just the problem with “echo” and “cat” that he send sometimes more Characters.
When I send “Hello” I receive “Hello”
When I send again “Hello”, I receive “HHello”

Did you have an idea? Minicom I have to study how it works.

Thank you!