Sometimes solutions are very simple. Openocd (Open On-Chip Debugger) is used on ubuntu for debugging and flashing programs to your target board. We are using SAM E54 Xplained Pro board. The problem started when we could not locate openocd config file for ATSAME54. After searching on google for a while we came to know that atsame5x.cfg we have to apply patch from openocd to get this working. As per openocd site they mentioned that support for ARM M4 series is added for microchip SAM D/E series controllers. We have downloaded patch updated openocd and after running it using following command, could not connect to board and got same error. $ openocd -f tcl/board/microchip_same54_xplained_pro.cfg Open On-Chip Debugger 0.10.0+dev-00409-g1ae106de (2019-03-18-12:24) Licensed under GNU