DS86 News - Dos Emulator for Nintendo DS - Maintenance work

Pate has posted some more WIP News concerning his excellent Dos Emulator for the Nintendo DS:

This weekend I went thru most of the log files I have received since releasing the 0.03 version, and added or fixed a lot of the issues in the log files. Thanks to all of you who have been sending me the log files, they are very useful in my attempt to improve the compatibility of DSx86!

I also worked on support for two games, Duke Nukem 1 and the original CGA Elite. I've had requests to support both of those, so I decided to work on those two specifically. Both are currently running, DN1 was only missing a couple of minor things, while Elite needed a bit more work. I haven't supported the DOS "buffered input" call (which Elite needs for it's copy protection system) at all yet, and adding it was rather difficult. It needs an active keyboard interrupt to feed it the keypresses, and the interrupt architecture in DSx86 is not re-entrant, so I could not use the existing DOS interrupt handler coded in ARM C language. I actually had to code parts of the DOS interrupt handler in x86 ASM to handle the buffered keyboard input. It felt a bit silly to code stuff in x86 ASM for an x86 emulator, but that was the easiest way to get it to work. The routine is still missing some standard features (like INS key handling), but it is working well enough that I was able to type the copy protection words from the manual and go into the actual game.


I was thinking of releasing the 0.04 version today, but then decided against it as I haven't had time to test the new changes properly, and I also haven't had time to go thru every log file I have received. I'll use the next week to make sure I didn't break anything with the new changes, and possibly test a few more new games, and then release the new version next weekend.