A while back I gott a nonfunctioning Sonic 3, board only.
Although it was reasonably clean, i didn't boot.
While doing random tests, I tried it with a Mega Key, just like this one:
It showed a message telling it was designed to be played on NTSC systems.
So, I played a little with the switches and it booted fine with all of them off.
Interestingly it didn't boot alone even with a game genie.
I quickly opened it to see what's inside and I only could find an epoxy blob, the 4 switchs and some parts marked as RPx, wich I suppose are some resistors associated on a bar.
I also removed the FRAM and the logic circuits around it, routed the ROM /CE to the 74HC139 pin 1 and got the same results.
Is there anything I can try to do to make it boot alone?
It's also missing all the capacitors, except the electrolytic one.
What capacitors are these? I think they're decoupling capacitors, but I didn't find an clear enough image to see its values, would they be 100nF (104) ones?
Also, it's not saving, I fount that specific FRAM chip (FM1208S) to be expensive, maybe I could use an SRAM on its place.
Just in case someone is interested, here is some board p0rn:
Better resolution here and here.
Oh, and I noticed I forgot to take a picture of the assembled board.
But I found a similar one here
If someone could please RE this board for me, I would be very happy.
Thanks in advance!
Although it was reasonably clean, i didn't boot.
While doing random tests, I tried it with a Mega Key, just like this one:
Attachment:
It showed a message telling it was designed to be played on NTSC systems.
So, I played a little with the switches and it booted fine with all of them off.
Interestingly it didn't boot alone even with a game genie.
I quickly opened it to see what's inside and I only could find an epoxy blob, the 4 switchs and some parts marked as RPx, wich I suppose are some resistors associated on a bar.
I also removed the FRAM and the logic circuits around it, routed the ROM /CE to the 74HC139 pin 1 and got the same results.
Is there anything I can try to do to make it boot alone?
It's also missing all the capacitors, except the electrolytic one.
What capacitors are these? I think they're decoupling capacitors, but I didn't find an clear enough image to see its values, would they be 100nF (104) ones?
Also, it's not saving, I fount that specific FRAM chip (FM1208S) to be expensive, maybe I could use an SRAM on its place.
Just in case someone is interested, here is some board p0rn:
Attachment:
Attachment:
Better resolution here and here.
Oh, and I noticed I forgot to take a picture of the assembled board.
But I found a similar one here
If someone could please RE this board for me, I would be very happy.
Thanks in advance!