A common hurdle in cross development is to get the communications set up properly between the target board and the development platform.
The GDB `set remotedebug' command can help. It was designed to help develop new remote targets; it displays the packets transmitted back and forth between GDB and the target environment. This command can be helpful in diagnosing communications problems, for example allowing you to observe packets not getting through, or noise on the line.
The set remotedebug command is now consistent among the MIPS
remote target; remote targets using the GDB-specific protocol;
UDI (the AMD debug protocol for the 29k); the 88k BUG
monitor; and Hitachi ROM monitors. You can set it to an integer
specifying a protocol-debug level (normally 0 or 1, but
2 means more protocol information for the MIPS target).
See section `Communication protocol' in Debugging with GDB, for
details.