Orange Pi 3-LTS how do i enable UART 3

[z28z34man]

How do i enable UART 3 in an orange pi 3-LTS. 

 

i checked the /boot/armbianEnv.txt file and it has overlay_prefix=sun50i-h6.  i then did a sudo armbian-config > System > Kernel > SYS210 Manage device tree overlays > enabled sun50i-h6-uart3 > reboot.  

 

after all that i am still only seeing ttys0 when i do a dmesg | grep tty

[Michael Robinson]

Have you tried: sudo armbian-config

[z28z34man]

yes i did a sudo armbian-config

then i selected System 

then i selected Kernel

then i selected SYS210 Manage device tree overlays 

then i enabled sun50i-h6-uart3 

then i rebooted.