First post, by mills26
Hi.
I love dos games and i wanted to compile dosbox for psp by myself, to optimize it for a couple of games (erase all unnecesary emulation, sound cards, etc)
I'm not a very skilled programmer, and i'd like a small guide to compile the eboot from source. Then, i'll just play with the code and try to learn from it.
I also sent a PM to crazyc (i suppose is the one who ported dosbox to PSP?)
Dosbox on PSP has a very jerky sound output, and emulation speed changes a lot depending on the game.
For example:
-"supaplex" works full speed using 2500 cycles, and it will just go slower with more tham that.
-Games with 3D gfx will run better until you reach 10000 cycles (wolfestein 3D or LBA2).
The main goal of this, is to create two eboots:
--1 to run "Little big adventure 2: twinsen's odyssey" (and surely some other 3D games):
if i force 10000 cycles it will became VERY playable on PSP, about 40% of the real speed.
Things it needs(these tested on PC DOSBOX ): cpu (12000 cycles), SB (it only needs wave playback), 8 MB RAM, 640x480 SVGA, (a TV mode could be added for PSP slim "720x480").
Things it won't need: mousse, internet, vga,ega,cga... adlib, gus, pc speaker.
--2 Emulate 386
Many 386 games will work full speed with 2500-3000 cycles, but the sound playback is a mess on PSP.
Things it needs: cpu 386 2500 cycles, OPL2 + 1 channel pcm, PC Speaker, mousse, 4 MB RAM
Things it won't need: the other cpu's, SB, GUS, SVGA, internet.
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A lot of improvement could be done for both versions, for example, make the sound card to be emulated by media engine or optimize adlib emulator.
If anybody is interested i'd love your help, PSP is a very good handheld for gaming.
We can always use an android phone, but these games are just not made for a touch screen...
Thanks a lot