unable to view uart messages from usb-to-tty adapter

[wahaha 4]

I am trying to view the uboot and boot messages on the tinkerboard 2s as it boots up, but it is failing to print out the message to computer terminal (via screen).

I have connected the cables to gpio pins 6, 8, 10. (gnd, uart0_tx, uart0_rx) as per image below.

from there, i plug it into the computer and used the below code to get the usb device that it is connected to

sudo dmesg | grep tty

Result : [21875.686247] cdc_acm 1-4:1.0: ttyACM0: USB ACM device

 

From there, I used: sudo screen /dev/ttyACM0 115200` to launch screen with baud rate of 115200.. But there is no output on the screen.

 

Not sure what is wrong? is Uart enabled by default?

 

[tooz 54]

hello @wahaha, 

please add the overlay to /boot/config.txt, save and reboot and see if the overlay comes effective 

sudo vi /boot/config.txt
overlay=console-uart0-overlay