You might add (see previous thread ) that you have a breakout board.
https://dl.openhandhelds.org/cgi-bin/gp2x.cgi?0,0,0,0,23,1626
Unbricking thread:
https://pyra-handheld.com/boards/threads/gp2x-black-screen-only-jtag-advice.77017/
Maybe @Orkie is around to assist.