Excuse my lateness; I've only just got around to going through my backlog of emails after my stay in Texas. On Mon, 19 Mar 2001, [ISO-8859-1] Marko Mäkelä wrote: > Last year, I promised to borrow my VIC-II collection to this guy for > measurements, but for some reasons I never came around to sending it. > Now it seems that he managed to come up with very good results anyway. I'll say! His page is *exactly* the sort of thing I've dreamed of for emulators for years. The results are entirely consistant with what I would have imagined about the VIC-II design process. Is Philip on the cbm-hackers mailing list? I'd like to congratulate him on this outstanding project. > Now we'll have to convince him to do the same research for the VIC-I and > the TED. Personally speaking, I think TED should be next. I'm biased, of course, but the TED chip is much closer in design philosophy to the VIC-II than the VIC-I, so I think it would be a logical "extension" of the project. I expect the luminance values of the TED to be slightly different than those of the VIC-II; at least that's the conclusion of my visual inspections. The chrominance values should present an interesting challenge as there are 14 of them; these must all be different as there is a seperate luminance control anyway, and they can clearly be seen on the monitor as distinct over all luminance values. One problem is that the three blues are *very* close together, but still 3 different colours on every TED I've examined. > I've noticed that some VIC-20s have very bright white colour, while the > white background on others looks more grey (C64 colour 15 or 11). I > wonder if there are other palette differences. My main VIC-20 has the > darker variant of white. I noticed some curious effects on my old 1802 monitor, with the white and red colours on a VIC-20 causing some curious waves in the horizontal raster display, as if the colours were in some way "too bright". This is less of a problem on the TV sets I use today, as I believe they can cope with higher input voltage ranges. Out of spec voltage ranges are also a problem on some of the Atari 8 bit computers. How many VIC-I variants are there? I've noted 6561Es in my very earliest VIC-20s (including the ones with PET keyboards), 6561-101s in the later VIC-20CRs, 6560-101s in NTSC VIC-20CRs and 6560R2s from the batch of chips Marko distributed. Is there such a thing as a 6560E, maybe inside the original NTSC VIC-20s? It's curious that the 2 pin American power plug design is incompatible with the 2 pin European one. Richard - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tml.hut.fi.
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