I tried to reproduce the problem to give exact details but now it doesn't happen anymore, even after several restarts. What happened before was that the emulator would run at 10-12 Hz when limiting speed and at 200 Hz when not limiting the speed. Something triggered this and I don't know what. I turned speed limit on and off several times then with consistent results. Now when I try it works as expected, 50 Hz when limiting and 200 Hz when not limiting. We'll see if it turns up again later.
Ah, I just found a bug in my internal function ROM prior to burning it, thanks to the emulator. VICE didn't emulate capslock but Z64K did!
Glad to hear the internal function ROM functionality I just implemented was of some use! There is still are lot of work to be done with the C128 emulator, especially with VDC, Z80, and clock stretching, but it is improving. I have a huge list of features I still want to implement, a lot contributed by Miro, but at the moment I am focusing on core functionality. I have managed to get my hands on a real C128D which should arrive early next week so I'm hoping that will greatly help with benchmarking the emulator against the real thing. I'm currently rewriting the VDC emulation to be able to show all Tokra's images correctly in all modes including multicolour interlace. I hope to have most of it complete by the end of this long weekend.
The images you have created have been invaluable with me being able to emulate the quirks of the VDC and VIC chips. VIC NTSC interlace was relatively easy to implement compared to the C128 VDC and VIC-IIe. BTW your message prompted me to go back and check the interlaced images on the VIC 20 emulator and I found an error with the reset code which was locking access to the drive after a hard reset that stopped me from being able to view the images. I have fixed that issue now and uploaded a new version of VIC 20 so the interlaced color retina images can be viewed again with no issues if the user used a hard reset instead of a reset when changing screen modes.
If any of you have any images you know display on a real c128 but doesn't show in the emulator please send me a copy and I will prioritize trying to support them. I'm still waiting for my 64KB VDC upgrade but I plan to do a lot more thorough testing of the VDC to make the VDC emulation even more accurate than it is now.
I haven't used IPaint before but I had a quick look for a copy to test with but I couldn't find an image to download.
BTW I've finally improved (actually simplified) the clock stretching in my emulator! The VIC version of Risen From Oblivion displays the all the images and the scrolling message that were previously corrupt at the start of the demo correctly now.
You could also test Hydro's Basic 7.80 on your emulatior.
Thanks for the copy of IPaint. I have greatly improved the interlace mode of my emulator so IPaint displays correctly now and Tokra's VDC-IHFLI and VDC-ITFLI modes display much better! See example of screenshots from emulator. Interlaced text and images seem to work correctly in all programs I have available including VDC Demo. I haven't test Basic 7.8 yet. I probably should open a new thread for testing interlace mode because I've already fixed the clock stretching issue this thread was trying to resolve...