Seems like uboot doesn´t want to get a newline, otherwise it behaves weird. #commands for setting Target-IP, TFTP-Server-IP-address should follow here.Įcho -n "1" >&5 did the trick for me. While true do #just for debugging (was command received?). Read output &5 # echo '1' for taking boot option 1 I am able to detect the string I am searching for, but as I said before - the router doesn´t recognize the command(s) send: #!/bin/bash Or do I have to send a special "control character" right at the beginning, for the router to recognize that "there is someone out there who is able to send me some commands"? Maybe I have to choose special options for stty? I am thinking that in my script, there are some parameters missing. Same behavior when using minicom + /dev/ttyAMA0 on a raspberry pi (ftdi device otherwise works as described). It just boots directly into the default option. The router does not care about inpu also the countdown is not runnig. Starts tftp-bootmode where I could input stuff liker server IP and so The router "boots" into the selected option.I am able to send a command/enter a number.Waiting for input until I enter a number or the countdown is over. Bootmenu is shown while a time is counting down, the device is.When using minicom with a ftdi-USB-UART-device directly (no with the script) everything works. It is a router I am connected to and I want to send the commands, after the uboot-menu has appeared. If this string is shown, some commands should be send back to the connected device. I try to use a bash script to watch the serial-port for a specific string.