Luca’s addition of Trivia R Us to the Crystal System driver, and discovery that it needed the stack aligned reminded me of something I’d looked at a long time ago with ‘Donggul Donggul Haerong’ another Crystal System game.
I’d made an observation in the past that ram writes on most Crystal System games were aligned, except on the two non-working ones, which at the time seemed like merely an interesting co-incidence.
Looking back at it there might actually be more to this discovery than it first seemed, because patching out the unaligned reads/writes (simply disallowing them in the core) allows the game to work 95% of the time. Sometimes, for reasons unknown it still boots up in a broken state so there is a possibility that the unaligned writes are a symptom of whatever is failing, and causing the RAM corruption, rather than the cause of the failure, or there could simply be multiple issues.
Either way, if you boot the game and it starts without a problem (no graphical glitches) you seem to be able to play it now. Due to not being 100% reliable the game will still be marked as NOT WORKING in MAME, but it has definitely improved.
The 2 Player mode, which switches to a higher 640×480 (presumably interlaced) resolution also doesn’t work properly, it runs twice as fast as it should and only updates one of the playfields correctly, I suspect this is some kind of raster effect involving changing the scroll-values mid-screen and the driver *really* isn’t set up to support this.
It’s possible the CPU can’t do unaligned reads / writes, or possible that disabling them in the core is nothing but a gross hack, it’s hard to tell as other games don’t seem to use them at all, although I would appreciate people giving the other Crystal games a good workout in 0.168 to ensure nothing has broken, if it has, obviously this progress will end up being reverted.
The game is often described as a modern take on Wonder Boy from Korea, it’s easy to see why.
Office Yeo In Cheon Ha also stops crashing with these changes (although there are still some ugly graphics) however not all controls are mapped, so again that one can’t really be considered working yet despite the improvement.
I also moved 2 other games which are meant to be basically Crystal System hardware (same integrated SoC but slightly different surrounding hardware) into the driver just in case somebody like Luca is interested in looking at them too.
Great work :o) is it me? or does this look like wonder boy?
this games looks top :)
All I can say is :
Thank You Haze !
That game is similliar to a net yaroze playstation game magazine.
Anyways it’s a great game.
Nice advances on Crystal System emulation, and thank you very much Haze for the explanation.
If you let me, can I ask if someone has tested or tried at least Wuly Buly and Urachacha Mudaeri? if i remember well they are both crystal system games (unprotected i think), so maybe they are ‘easier’ (i know there is nothing easy at this point) to take a look than others.
I will check this games on 0.168 to test if these changes made a ‘side effect’ on the working ones.
Thanks in advance!
those two games aren’t dumped, I was hoping they would be dumped in order to tell us more about the hardware (one of them is unprotected) but in the end the trivia game (that had been dumped for ages, but nobody noticed was on crystal-like hardware) told us a few things.. could be that they’ll still be helpful if they get dumped tho..
Oh I see, what a pity they are still waiting for someone to be able to dump them.
At least as you said before this new game brings new ‘clues’ to work in the right direction with the driver. New additions are the best way to acquire more knowledge about a system.
Thanks for your quick response Haze, much appreciated and excuse my english.
So, they’re in Dumping Union possession but still waiting to be dumped? Huh, okay.
http://www.mameworld.info/ubbthreads/showthreaded.php?Cat=&Board=news&Number=342456
not everybody has the tools to desolder / dump the Flash roms, and Guru is generally considered untrusted by the DU*, and a liability to send things to (his recent selling of PCBs that some members are adamant were loaned with a view to being returned, rather than sold for personal profit has pretty much cemented that view) so they remain undumped until such a time as there are enough for it to be worthwhile sending them on to a member with the right tools..
* as always, the views of an independent party such as the DU don’t necessarily reflect the views of the team, much as Guru’s own individual views don’t.