Stef has posted some very interesting developments in the DCEmu UK Forums , heres the post:

Well, i’ve some news about C68K (a new 68k core i wrote in C, designed for speed) :

I finally implemented all opcodes, but there are still many bugs to fix
I first tested it on a PC Genesis Plus version… i implemented “on-the-fly” core switch and it worked well, i succefully played with Sonic 1, Sonic 2, Sonic 3, Aladdin … i had to switch to musashi sometimes because of multiples bugs in C68K.

Nice, it (almost) works on PC, what about the DC ?
So i implemented C68K in Genesis Plus DC, but just with inlines methods using musashi or C68K depending a #define (understand by that : no “on-the-fly” core switch as PC version)…. then it failed
even with -O0 optimisation

So i did a new PC build with inlines methods instead of the complete multi core support and i got the same result on PC version… weird, i finally discovered that sonic1 (my favorite test rom) didn’t work with that implementation hopefully Aladdin did work

-> testing DC version with aladdin (arg 1.2 MB to upload instead of 350 KB for each test)…
IT WORK ! at least with optimisation set to O0, and believe me, with O0, Genesis Plus DC doesn’t run very fast (about 11-12 FPS)…

After severals tests, i discovered that -O1 optimisation level just break C68K
but -Os does work
unfortunatly, C68K wasn’t designed for -Os optimisation, and i think it perform better with -O2 than -Os but at least i can get it to work with optimisation…

I don’ really benched C68K versus musashi on DC, but i will do it that tonight and report result here…

For those who want to include C68K in their project just for testing purpose (remember the core is still in development), i can give a pre-compiled obj file (-Os optimisation level) with .h file and an interface which permit to use musashi or C68K depending CPU68K_USE_MUSASHI or CPU68K_USE_C68K definition… some stuff as memories handlers and interrupt callback need to be modified also, the current C68K interrupt callback is wrong, i’ll redo it later as musashi one.