@hreintke so this is the main issue with the debugf. Is this an issue just in sming or is it an issue of the SDK? This is what i am trying to figure out. If i disable the debugf, i will loose all the debug stuff that use the debugf and this is not what i want. Will I have the same issue if i redirect the debugf to send packet for example in a udp connection, or is it only related to the telnet stuff? I dont want to lose the debugf from the SDK and also i want to use the serial uart0 for another function. Can i do that? Or not?