Connect GDB to the GDB Agent as described in Section 4.6.3.2.1 and load a program to the device.
After the debugger has stopped the program at a breakpoint, you can step through the code:
To execute the source line, type next. next does not step into functions, it executes the complete function and stops on the line following the function call.
To execute the next source line and step into functions, type step.
To execute the next instruction, type nexti.
To execute the next instruction and step into functions, type stepi.