DSx86 v0.23

[luke_c]

DSx86 v0.23
Update, DSTwo version in the works!

The Intel 80286 emulator for the DS, DSx86 has been updated to version 0.23. This update only features minor changes. See the changelog below for more information. A Supercard DS TWO version is in the works and goes under the name of DS2x86, look forward to it in the future![/p]

• Maupiti Island memory allocation problem (as mentioned in the previous blog post) has been fixed.
• Support for tweaked 640x400 EGA mode added (used in Mahjong Fantasia, for example).
• Fixed the hang in Bart vs. the Space Mutants. The hang was caused by two timer interrupts happening immediately after each other. This should not normally happen, but as DSx86 uses the host machine timer IRQ to drive the emulated PC timer IRQ, it is possible for a timer IRQs to happen during screen blitting, which in turn might have interrupted the handling of the previous timer IRQ. I adjusted the timer IRQ handling so that timer IRQs that happen during screen blitting are ignored.
• Fixed the Space Hulk "Error in MIDI code!" problem that was introduced in 0.22 (caused by the new AdLib Timer 2 handling for B.A.T. 2). I improved the AdLib timer handling so that both B.A.T. 2 and Space Hulk are happy.
• Fixed the unsupported INT call at the start of Fire & Ice (it tries to load custom EGA fonts, which is not yet supported).
• Added some missing graphics opcodes, based on the error logs I have received.

Other notes: I also spent several hours tracing the null pointer jump problem in the Superhero Legend of Hoboken game, but could not fix it yet. I found out that the problem is caused by a routine overwriting data in the stack, so that the routine then returns to address 0000:0000. This same routine is used without problems hundreds of times before it fails, so tracing the actual reason for the failure is pretty difficult and time-consuming.

Not a lot of changes, and as I am moving my focus from DSx86 to the new SuperCard DSTwo version, at least for the time being, it is possible that DSx86 itself will progress very slowly for a while. I will possibly increase the two-week release cycle, especially if I have not had time to do any worthwhile improvements.

Spoiler: DS2x86 Progress

I have not yet received the free DSTwo card that SuperCard has sent me, so I have not been able to fully start coding for it yet. I have been learning MIPS assembly language and have started converting some of the ASM macros I have used in DSx86 to MIPS ASM for DS2x86, though. I am using mostly the same ideas that I have used in DSx86, but will include 386/486 opcodes from the start, and will switch from using the CPU flags directly to a Lazy Flags-type approach. MIPS has so many general purpose registers that I believe I can fit the lazy flags into registers, which should make the code run reasonably fast. Not as fast as the ARM version, obviously, but on the other hand the MIPS processor has quite a bit higher clock speed.

I hope the DSTwo card arrives next week!

 Download

 Source and Project Page

 Compatibility Wiki

 

[indask8]

This is a good news.

DS2x86 is certainly gonna be the first emulator homebrew made for DSTWO.

 

[Costello]

wow that's an amazing emulator, i had no idea it existed!
emulating PC games on the DS... I didn't think the DS was powerful enough for that!
should be awesome on the SCDSTWO

 

[phoenixclaws]

I've been following this emulator from the start. I've been glad to read his blog every sunday and see that he is eagerly interested in a SCDSTWO DS2x86

. I can't wait to see 386/486 programs running on it

.

 

[Kitanode]

Hi, can someone plz show me how to get win3.0 working on this emulator.

I have disc images(.ima) of the five floppies that install it but i'm unsure of how to get it working on the ds.

Cheers.

 

[Another World]

i wish more devs i contacted wanted to move to the scds2. still this will be a nice start and i hope we get some 386 emulation out of the scds2. thanks for the updated post luke.

-another world

 

[RupeeClock]

Oooh, news of the first third-party DStwo emulator.

 

[dnniwa485]

Windows98 anyone? lol

i hope i can play some games like Red Alert 1 on DS... well the game is operational on DOS mode.. so it shouldn't be a problem.

my DSTWO is ready for DS2x86

 

[Marlonguppy]

Yeah, i have an iPlayer.
And no, not a SCDS

.
iPlayer just doesn't release their SDK, so the card is "forgotten".
I don't like it for those who buy an iPlayer.
I can't also buy a SCDS2, because, they are banned now in the Netherlands.
So. The only thing i do is waiting on nothing. Mailed them 5 times, with the answer NO.
Do we have to take action on the iPlayer?
Yes. I'm also a dev. so yeah, that really sucks.
Ah, well nice job, anyways.