if we short TX and RX of UART0 for loopback test. is it possible that this can damage USB line(micro USB) or can create any issues?
I don’t think it’s possible to damage USB line in this way, but this is quite a bad idea, because such short may cause signal contention.
Thanks for your reply. it is great for us
Now, my board is connecting properly on ssh but not on serial(no any boot messages coming on serial(usb)). we thought it happened due to shorting UART0 pins.
so can you guide possibly what is reason behind it or how can we fix it?
Try connecting to each of the serial ports exposed by FTDI chip. One of them is used for JTAG, not for UART.
Tried with both serial ports /ttyUSB0 and /ttyUSB1 found same result no boot messages