UART on Orange Pi Zero

[rohinrohin]

I was unable to get UART working on my Orange Pi Zero. Note, that I am not trying to use UART to access the terminal, I need to use the UART port to say connect to an arduino, etc. 

 

 Here is the output of some commands that I thought may be helpful. 

uname -a
Linux orangepizero 4.10.0-sun8i #14 SMP Fri Feb 24 03:02:58 CET 2017 armv7l armv7l armv7l GNU/Linux

dmesg | grep TTY

[    0.000000] Kernel command line: root=UUID=b5fc390b-23ef-47a8-83fb-0fd94a3d2dcc rootwait rootfstype=ext4 console=tty1 console=ttyS0,115200 cgroup_enable=memory swapaccount=1 hdmi.audio=EDID:0 disp.screen0_output_mode=1920x1080p60 panic=10 consoleblank=0 enforcing=0 loglevel=1 ubootpart=8b708352-01 ubootsource=mmc   sunxi_ve_mem_reserve=0 sunxi_g2d_mem_reserve=0 sunxi_fb_mem_reserve=16
[    0.001005] console [tty1] enabled
[    4.126456] console [ttyS0] disabled
[    4.146689] 1c28000.serial: ttyS0 at MMIO 0x1c28000 (irq = 37, base_baud = 1500000) is a U6_16550A
[    4.146761] console [ttyS0] enabled
 

Here's how I tested communication with UART. I wired up the pins (RX <--> TX) as per the pinout at http://linux-sunxi.org/Xunlong_Orange_Pi_Zero#Locating_the_UARTI would then do, 

screen /dev/ttyS[12] 57600
[screen is terminating]

Any help is appreciated. Thanks!

 

[zador.blood.stained]

Any help is appreciated. Thanks!

Additional serial ports are disabled by default, you need to activate them by either patching the Device Tree or using Device Tree overlays.

[martinayotte]

add "overlays=sun8i-h3-uart1" in your /boot/armbianEnv.txt and reboot.

[zador.blood.stained]

add "overlays=sun8i-h3-uart1" in your /boot/armbianEnv.txt and reboot.

Please, this feature is not yet announced. I don't want to go through the whole forum to delete or edit overlay names in case anything changes here, we already have too much outdated info on WIP stuff.