UART enable


I have BBB rev.C, and i need to enable two UARTs for use.

I added to the /boot/uEnv.txt file


In response to ls - l /dev/ttyO* I get

lrwxrwxrwx 1 root root 5 Oct 17 13:22 /dev/ttyO0 → ttyS0
lrwxrwxrwx 1 root root 5 Oct 17 13:22 /dev/ttyO1 → ttyS1
lrwxrwxrwx 1 root root 5 Oct 17 13:22 /dev/ttyO2 → ttyS2

But after echo -ne ‘123’ > /dev/ttyO2 (ot ttyO1, ttyS1, ttyS2), device connected to serial port not receive anything.

In response to dmesg | grep tty*

I get

[ 0.000000] Kernel command line: console=ttyO0,115200n8 capemgr.enable_partno=BB-UART1,BB-UART2 root=UUID=4dfadb43-f008-4c9f-8003-74fa96a8fca8 ro rootfstype=ext4 rootwait coherent_pool=1M quiet cape_universal=enable
[ 0.000392] WARNING: Your ‘console=ttyO0’ has been replaced by ‘ttyS0’
[ 0.174010] Setting up static identity map for 0x80008240 - 0x8000828c

Did you also set the baud rate and framing settings?

stty -F /dev/ttyO2 115200

Adjust for your requirements, see `man stty`. Also check pin
configurations to ensure the signals are being routed where you expect.