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How experienced were the designers of the Pet or Vic 20?

How experienced were the designers of the Pet or Vic 20?
I head Vic chip has delicate timing so I am wondering how experienced they were.

The VIC timing came from the

The VIC timing came from the chip itself which was mostly a compromise given the maximum performance of the day.  Mostly the signals could change between min and max at hi and low voltage and at high and low temperature.  Then the drams of the day also had variables.  Then the fact that they did not have an accurate transition to switch the DRAM addresses from Row to Column topped it off.

So the Vic based C64 was truly a consumer commodity, if a system reset every 30 minutes we still had your money.
At the heart of the PET was Chuck Peddle and the 6502 designers who really knew their stuff coming from system design at Motorola. The VIC I & II had pretty good timings though I heard that a non-hardware person may have done the internal power supply  for the VIC 1 which got too hot necessitating a VICii

Too Hot

Bil, that sounds fascinating!  I mean thermal tolerances and all.  I've never seen anything like this on-line, so if you could find some info about this, I think the Commodore community (definately me personally) would such info truly mind-expanding!
Also, if you or ANYBODY knows why the originl VIC-I fails to generate interlace video on PAL systems... that would be cool.  Obiously an interlace image needs more than 256 rasters...but NTSC (works) needs 525 rasters while PAL (625 rasters) fails... they both need 512+ rasters... the only differnce I know is that PAL uses 312.5 rasters/field while NTSC uses 262.5 rasters/field... in either case, the count exceeds the nominal 8-bit limit (9-bit if you count 0.5)

I'm kupo for Kupo nuts!

The picture I'm getting is

The picture I'm getting is that the design team were from G.E. or Motorola and because Commodore lost Chuck Peddle, they really lost the ability to make and design a lot of products which I think would have solved a lot of problems.

Chuck was in the processor

Chuck was in the processor side, Al Sharpentier and Bob Yannis designed things like the VIC chip and the SID chip, both of which went into the C64 which sold 27 million.

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