#SNES9X BAD CHECKSUM FIX CODE#
#SNES9X BAD CHECKSUM FIX PLUS#

But I think chances are good that much could be learned already without this nontrivial and time-consuming procedure. The endgame would be an eventual decapsulation, imaging and analysis of the die, as has been done and is striven after regarding other chips, ideally different variants so that they can be compared. Perhaps the smaller but also affected SA-1 speed test ROM could be a good starting point. So the next step would perhaps be to logic-analyze the SA-1 pins to get an idea of what happens after the SNES system is powered on, which, given the existence of different SA-1 variants, would also have its own merits with regards to emulation accuracy / preservation.

#SNES9X BAD CHECKSUM FIX CODE#

Obviously, the patches do something that official ROMs don't, but comparing the code introduced by the patches with the code of official SA-1 ROMs may be like looking for a needle in a haystack, the cause may be timing-related et cetera. Indications are that officially released ROMs that make use of the SA-1 work with all SA-1 chips. But what's more important is that the patches can be improved to work with all of them, so that one wouldn't have to worry about this anymore. It's inconvenient if one intends to build a conversion and fishes out a non-working exemplar. While sample size was small, a change in the package coinciding with a change in circuit design, in turn leading to some nuanced changes in behavior, would have been plausible.

#SNES9X BAD CHECKSUM FIX PLUS#

On the plus side all this soldering practice has really helped improve my soldering skills, which was one of my main aims of this project, so that's a win! But this has definitely got me very confused. The last thing I can try is swapping the RAM off the working Japanese version and seeing if that changes things, as maybe it's a faulty RAM chip. So the ROM chips are both working fine on the Japanese build, the SA-1 is working fine but both dot and chamfer behave the same, and the game runs fine with the original ROM chip of PGA European tour on it. Removed the RAM and inspected the pads, but everything looks fine. Put the ROM chip off the PAL version onto the Japanese version and this runs fine. Swapped the ROM for the working Japanese version of Gradius, and this had the exact same booting issue, stuck on the white boxes

Passed this test as the game booted and ran fine Swapped the ROM for the original PGA ROM to confirm SA-1 was working OK. Same boot crash issue where it only shows the white boxes I replaced the SA-1 chip with a chamfered edge one. It would be even better if the default attack was the sword, like in mmx4, but since there is only 1 animation for the sword I guess it could get boring and since the game is made with you beign able to shoot in mind, it could get tricky at times.Īnyway, good job with this hack, I really like to have a reason to play this game again and feel chalenged with it again.I have done quite a few bits to try and get the PAL version to work, but to no avail. Also, it would be nice if the second charged shot was only available once you obtain the buster upgrade.

Would it be possible to make his charge shots not keep you from advancing ? It really slows the action and can be a problem when fighting bosses, maybe im just too used to playing as X tho. I really like that it is possible to use the air dash with zero in this hack, but there is something I dont like about zero. I also worked on a hack which changed the level something like 14 years ago with a guy name elixirnova, it didnt really get far tho, only 3-4 rooms were changed before we abandoned the idea. I always liked mmx3, even tho alot of ppl argue its not as good as mmx or mmx2, mmx3 has always been my favorite, back in the days I made a cheatcode that made me have a maximum of 1Hp and managed to beat the whole game up to the final boss.

Snes9x bad checksum fix