Rock64 <--> Rock64 Serial Connection

[barray]

I'm trying to troubleshoot a booting problem with my Rock64 with an openSUSE Tumbleweed install on an eMMC.

If an SD card is an option, this might be easier.

When I cat /sys/firmware/fdt while using my USB UART the output is garbled.

I'm not sure cat handles unknown bytes correctly, or it's incorrectly trying to escape data. Also I am not sure how cat will handle pauses in transmission (blocking vs non-blocking, 7-bit ASCII vs 8-bit ASCII vs UTF-8, etc). Checkout socat and the options it offers: https://stackoverflow.com/questions/2637...connection

When I hookup the tx > rx and rx > tx , both Rock64 lockup. So, is there a way to use the 2nd Rock64 in this manner?

Lock-up is likely quite bad. Check they have a common ground. Even if they have a common power source, by the time it has been through a USB cable and power modulator they may drift.