Yeah, the COP444L in Space Invader was RC, too, which was one of the reasons I first tried dumping it without doing the setup stuff- I wasn't sure how to drive it. Luckily, the game sets the L port as all outputs, so that part of the setup was taken care of for me. I just used 2 AA batteries on the SO pin with SI grounded to get into ROM dump mode. That worked fine when I powered the chip with 9V, but at 5V I had to add a resistor to SO to get it to go into test mode. The game uses SK as an output, so I lost the data ready signal, but it was easy to figure out the center of the bits