C64 & 1541 core status and compatibility list (Page 2 of 3)

Yes, I suppose several glitches are based on a single issue, but I am sure there is more than one issue to fix

I saw your download above and could check it. Your ghost'n'goblins version seems to be different to mine, it get stuck on the splash screen - strange... But Zynaps is working fine, no glitches - can you send me a screenshot, please? I'd like to see and reproduce it. I just sent you a PM so you should have my mail address.

Wings of Fury seems to be a D64 file with additional disc error information, this is not processed yet in my media emulation (that's what I want to implement soon) - I'd guess that is the reason why it gets stuck (I just get sound with a black screen).

I go to any user profile (click on the user name in a post) and select "Send forum email" you will receive a message on the e-mail you used when you registered for this forum. This avoids posting e-mail adresses to the public. In your profile you should have (at least) set "Hide your email address but allow email via the forum." in the profile -> settings -> email settings (this is the default setting).

Edit: ok, i just tried it for my own account, it seems that Mike has disabled this function, even if it is enabled in the profile.

Yes, the C64 has a quite strange ratio which needs to be scaled to be used on a VESA compatible pixel clock with minimum frequency (= to get HDMI/DVI work properly). If it would not be done, the picture would be too small in X direction and the overall aspect ratio would be wrong. Unfortunately this scaling is an odd factor and not something like e.g. a factor 2 or so. There are ways to improve this (like it is done on a PC with an emu with pixel-based filters) later on...

Edit 2: I don't see the effect you show on youtube on my monitor, I'll try on a different one to check if I can see it there...
Do you use a digital (HDMI/DVI-D) or analogue (VGA/Scart/Composite) monitor input? Could be a sync issue of your monitor in this mode - the problem is (as mentioned) that it is not really VESA conform and there is no guarantee the video will work correctly on any monitor...

The only way to fix is properly (including aspec ration fixes) is to go away from a native output to a framebuffer setup, like it is done on a EMU (where the video runs on a totally different frequency/resolution and the core just "draws" the picture to an own video memory of the graphics card). This will introduce other issues like tearing, though (as you can see in fullscreen mode in this emus).

Wolfgang, just wondering if you missed this:

Oops, didn't see this... so, here we go.

1. Thanks for the explanation regarding the C64 ratio. Guess will be looking for some sort of fix later on!

2. The Youtube video didn't come out very well, I will try and take a better one hoping that the artefact is more visible. I tried with both DVI->VGA and DVI->HDMI and the artefact was present on both.

3. Ugh... tearing.

Well I tried Zynaps on a 3rd display, and I got the same issue. Hmmm....

I made another video comparing both sides. If you look closely, on the left side of the copper effect there are short flickering vertical lines, on the other side it is perfect.

https://www.youtube.com/watch?v=XK1F3rbyT3k

Woah.... I'm impressed. The funny bit is that I do have a real C64C and tested Zynaps, and it didn't have any of those glitches. Not sure what to say now! Nevertheless, Chris, thank you for the headsup!

Awesome will test the same games I had problems before, see if these are fixed with the latest core.

One question regarding the non exact screen ratio... how come is it so hard to fix? Isn't C64 resolution a fixed one? Sorry if it is a stupid question

Thanks Wolfgang, hopefully one day the display problem is fixed, if possible - means the C64 I have in my office won't be retired for the time being.

Regarding the C64 games, thanks for saving me some time, I guess these will be compatible some time in the future.

Found & fixed a nasty interrupt glitch in the VIC-II code. All games above work now (and many more). There are still some minor sound issues (have not checked yet Mikes SID implementation), but all games I found and tried were playable.  I checked as reference all games as they are distributed on the DTV - now they all work on the Replay core as well!   

Will do some more testing and prepare a release this weekend (maybe even today) - so please stay tuned...

Edit: just released in my "pre-release" thread here...

Edit 2: let me know if there is a game not running on this latest release to have a base for further debugging (be sure it works on e.g. a real PAL C64 with a sd2iec connected using the same D64 file) and it does not use some odd copy protection or requires a NTSC C64 causing the stall.

Great. I think the issues are related to the noise generator and some require the "bad" internal DAC offset of the SID to be there (e.g. impossible mission for the speech at the beginning - currently there is nothing to hear). I did small fixes I checked in already so that some games can detect the SID, although I think this fix is still not fully correct.

I'd leave the core this way for a while - as it is working pretty well now (only very few and IMHO more irrelevant CIA issues left with the Lorenz test) - and focus on some other things - besides using it to play, of course. Just to free up my mind a little...

I am pretty sure that Impossible Mission and other programs that do speech are bit banged (digitized) data.  I know the CIA is used for timing of these.  The Covox digitizer did this for playback and that was popular with everyone, including game developers.

Tested on C64 today: Bandits works perfectly on FPGA Arcade. Boulderdash (No-One's collection) works, but has sounds glitches. The sss, sss, sss of the movement of Boulderdash is not heard. Also the explosion when he dies is not heard. Something in the noise generator maybe ?