Hello Everyone,

I'm currently visiting my parents and helping them with some projects around the house. I decided while I was here, I'd take a look at their Stellar Wars pin which hasn't worked in years.

When powered on, the GI turns on, voltages from the power supply are correct, fuses are all fine. Most of the time on startup, both LEDs light on the CPU board and then turn off. Nothing from the displays, no sound, the coin door inside buttons and the Master Command button on the CPU don't seem to do anything. When you press the self-test button on the CPU, sometimes both LEDs flash twice and then go out (showing that it passes), sometimes one or both LEDs stay lit. Simply turning it off and back on again changes the result.

The batteries were relocated a long time ago, and there is no corrosion damage on the board. I re-seated all of the socketed chips and re-flowed all of the header pins on the CPU and driver board which made no difference. I'm trying to isolate if it is a CPU board issue or of the ROM chips have failed. Are there common failure points with the System 4 boards? I don't have another System 4 CPU board to swap in or another set of rom chips for the game.

In doing some Googling, a replacement CPU & Driver board is in the $400-500 range, and I'm not sure if they want to spend that kind of money for it (They have 15-20 pins, so one not working hasn't ever been an issue.) The replacement board says it fits System 3-7, which leads me to believe there is some cross-compatibility between the different generation CPU boards. They have a Black Knight (System 7). Is it possible to run the Stellar Wars ROMS from a System 7 board (from Black Night) for testing to see if the ROM chips will boot in that board? They also have a Tri Zone (System 6) in storage. I have no idea the condition of the boards in that since I've never seen that one on. Same idea though, would a System 6 board run the Stellar Wars ROMs (assuming those boards are any good)?

Any thoughts or advice is greatly appreciated.

Thanks everyone!

Thanks. I appreciate the link. So it does look like I can run the Stellar Wars ROMs in a System 7 board. In addition that's good to know about the logic probe. I wonder if I've got an issue with the reset circuit that isn't allowing the CPU to boot. I'll have to look into that. I know I tested the voltage at the power supply. I'll check test point #1 on the CPU board to make sure it's actually 12V there and not dropping somewhere along the line. I know the page said 11.5 is fine since the 12V is unregulated. Do you know how low is too low?

Tried booting the rom chips in a system 7 board. No luck. Tried 2 other power supplies. No good. So I guess the rom chips are dead.