Recent content by Ryoandr

Ordered from SYG, thank you for making a new batch

count me on the train

I am thinking L0 rom, or NEO-ZMC2. L0 handles vertical stretching, but the fact that you get alternating vertical lines on the solid blocks makes me think it's more likely the ZMC2 L0 is an SMD rom on MV1A, so you need a donor or bodge a DIP EPROM, even for just testing, and of course ZMC2 is...

There are some ceramics but it's very unlikely they are bad Since it does some kind of boot, P1 might be fine. P2 is a Toshiba and these have decently high failure rate in either carts or boards (bios) Unibios CRC check is a good start. And if a P rom is bad the good thing is they are...

It's a data error. The quote you posted is for address error. Bad ram chip is very likely in your case Also it's at 008000 which is the start of 4k / Fast vram, which are usually in DIP form (the CXK5814 in your case as with most AES I believe)

https://wiki.neogeodev.org/index.php?title=NEO-D0 check all the purple pins, Xin / out is the master crystal, all the others are outgoing clocks. If all are pulsing check if each clock actually go to each chip needing it. check 68k address / data lines activity, each (I think) should be pulsing.

That fast click means something early is bad. Do you have something to check activity, at least a logic probe, or an oscilloscope. Main crystal (if faulty usually results in literally nothing, not even click of death) goes into D0 that divides for almost all clocks. Some ICs might stick an...

Does game actually launch ? Do you have sound, through either AV Out or headphones jack ? Did you try on composite cable, on a crt ? I have found that some MVS and pretty much all AES I've tested tend to have sync signals that throw off modern hardware, displays, scalers, etc.

Bro that's wild. Congrats for getting it done and fully documenting it

Check activity on test point TP1 (scope or logic probe), it goes high / low every second. If it doesn't, well there are several points to check : RTC power line 32.768 khz crystal, should be pulsating on at least on one leg crystal capacitors C2 C3 RTC itself, NEC µPD4990

I'll go on a limb and say this doesn't look too terrible. As you say you can retin exposed traces, and maybe bodge wire if some lines are cut. The real work is figuring out if a chip is dead on the top board. You can do tests with the bottom board only with diag bios.

I already tried a Magician Lord convert on modern boards and doesn't work, maybe with extensive rom data manipulation it coukd be done, as earlier games had ADPCM A / B stored separately. C data also needs some work as there are some glitches. Ultimately I used a puzzled donor. Repro PROG-EP and...

Capacitors labelled PC are Power Capacitors, 100nF ceramic. They are typically used near every IC to filter their switching noise. However they are not critical. Watchdog loop is CPU not getting program to execute right in one way or another basically (please all experts here correct me if I'm...

CRE401 can fail internally, on each line there's a pull up resistor, an inline resistor and a capacitor to ground. Cap failing short makes input always on. https://wiki.neogeodev.org/index.php?title=CRE401

MV1B has no F0 However, looking at pics, it looks like dips are connected to a NEO-BUF, which are notorious for failing.