How to see serial console through USB TTL?

Hello everyone~

If I set printk("hello world"); in my project (main.c), I wanna to know … how to see this serial console through usb TTL?

About TTL , I found this pin map ( and use the UART1_TX and the UART1_RX and 1 GND (In the upper left corner) to connect my USB TTL. And input screen /dev/tty.XXXX 115200 on my linux computer. But … it doesn’t seem to work .

oh … I find the correct way …

It should use the TX1 and RX1 and gnd pin ( in the bottom right corner ).