Agx devkit can't use uart1, during system boot phase

agx devkit uart is used by uart1, and 40-pin Expansion Header are pin 6/8/10.
uart only use when system is started, but uart is no log during system boot when power is on.

I already test cases:
1、when flash jp4.6.2, uart only use when system prompt is appeared;
2、when flash jp5.0.2, uart have few log when booting and lost most log until system is started.

maybe uart is disabled or uart is switched during boot.
please check the root cause and solve it.

hello samwise.yang,

what’s your actual use-case, are you going to check bootloader logs?
AGX Xavier is using combined uart, you may setup connections with port J501, a micro-USB connector which provides access to the UART console.

yes, I want to check bootloader log.
micro-usb is the uart console and actually ttyUSB3 is OK.

Thanks a lot.