Unfortunately I kinda lost interest in the project due to lack of real hardware to test on, so I’m not sure if what I’m doing will actually work. My test environment is just a real IO card but the game running on modern Linux.
Right now the animation conversion tool is written in JavaScript...
Hmm, are you running it on a bench or inside the machine? Check with the scope all data and address pins on the chips, make sure everything is getting a good signal.
Did you try shorting pins 25 and 26 together to force the cpu out of reset? While shorted you may get the flashes telling you that the board is working but there is something wrong with the reset circuit.
Also were you able to distinguish between the two roms that looked very similar? Perhaps...
One other thing you can try while waiting for those roms to arrive is short out pins 25 and 26 on the CPU to see if you get any life, this will force the reset circuit to go high and allow the cpu to attempt to boot. See the flash codes section here for more info on how the watchdog circuit...
Good luck!
What's your plan for replacing the battery? Seems like everything has its pros and cons, I'm debating trying something new and buying a small li ion charge controller/ protection board and use a 18650 battery, Ofcourse isolating it using a diode like all other battery solutions. If...
For me I had zero light flashes, sound board would do a frequency sweep sound and a constant buzz.
Bypass caps are all the big green ones. They are trash just replace them all with 103 ceramics. Check the 5v at the ceramic capacitor just after the battery charge circuit. In my case it was...
Hah, funny I just finished repairing my old Coney Island board yesterday. let me know if you have any other issues, I’m putting together my repair log now. I bought a whole bunch of chips I didn’t need when the root issue was the bypass caps.
Yes the regulator and resistor getting hot is normal, that's just them burning off the excess power as heat to regulate it to 5v. once you reinstall bypass caps and chips I would suspect the voltage to drop a bit more on the resistor and for that to get hotter.
Note I would not connect this to...
bingo, with it removed are you getting 5V? It should be safe to power up without it. Looks like it’s just there to protect any potential over voltage from a back feed.
If you have a spare 7805 it wouldn't hurt to try and replace it, however it's to be expected that both of those components get really hot in the state that it's in right now.
The way a 7805 works (broadly) is that it converts any voltage above 5v into heat, so say you're drawing 1A at 5v and...
+1 on the bypass caps, pull them all and see if the voltage comes up, if it does replace them all. I have a gameplan mpu-2 that I just replaced far too many chips before realizing the problem was with the caps pulling the voltage down on the ram chips causing the entire data bus to go all wonky.