fascinating, iam looking forward to this project.
but what you mean with "I have compared the gameplay of Giana Sister on C64 emulation and FPGA. The FPGA wins, no doubts" ? do you mean that on emulators it don`t run that smooth in scrolling? iam a big fan of emulators and had much fun over the last years using ccs64, vice,win-uae,zsnes,gens plus,magic-engine,stella,mame,project64,epsxe,visual-boy.
The scrolling was not smooth (some tearing) because of the scanrate mismatch. Plus, the character was not so responsive. I think this is due to windows XP missing some key inputs from the keyboard. I used VICE but I have noticed the same issue under WinUAE. Another point is that there is some delay in the sound output. The computer used was a laptop with a 1.6GHz Pentium-M. On the other hand, with the FPGA, using a speedking joystick or the joystick emulation on the numpad, no problem at all.
and by the way, i have an "1541ultimate" for my c64. very cool hardware. do you know this?
Yes, I read about it and I do not need it since I also integrated the VIC-1541 in the FPGA.
I tried a D64 image of Summer Games II and it perfectly worked. Currently, I can load P00 file in less than a second (this is what you see in the video). I wrote an auto-boot menu that scans the P00 files and display the available games. I also put an auto-start feature so you do not have to type "RUN".
The next steps are to implement a pseudo stereo SID mode (I put two SIDs already but one is not used by most of the games/demos). I saw that Jeri Elsworth did an experiment by "detuning" the second SID. I think I will do that and add a delay to give some spaciality.
I also want to accelerate the D64 reading by adding a little bit of VHDL code and by patching the 1541 firmware and the C64 Kernal.