If you read this analysis, http://www.seanriddle.com/blitter.html , you’ll learn that the Williams Special “Blitter” chips are the key to why a game like Robotron could exist in 1982. Greg Wepner is the guy who actually designed the special chip circuit.
Although, the discussion gets very deep and technical quickly, it is relevant to remember what is being discussed is a physical chip.
See below for a glimpse into the micro world of computers!
High-Res image of this available at http://www.seanriddle.com/sc1die.html
Insights from Sean, Feb 2013-
- Decapped a Special Chip 1 blitter chip and took pictures of the die inside.
- Low-Res thumbnail made from 80 pictures: www.seanriddle.com/sc1_metal_826x720.jpg
- The die is about 1/10th of an inch on the long side, so I have to be careful not to sneeze!
- How the pins on the chip connected to the pads on the die (the 38 squares around the perimeter – the dark circles on them are where tiny wires connected them to the pins on the chip)
- Left center is the name of the company that made the chip, VTI (VLSI Technology Inc).
- Right center looks like someone’s initials: HLL?
- Center is the part # E2001.
- There are some registration marks scattered around; squares and lines that show that all the layers are lined up correctly.
- The gold-looking areas in the picture is a layer of metal that was deposited as the top layer.
- After I get a good picture, I’ll use acid to dissolve that so I can get a picture of the connections below. You can see some of them now, but some are obscured.
Further study of IC reverse engineering:
- old VLSI and MOS design textbooks from Abe’s Books
- John McMaster has done some analysis of the SC1 die shot: http://uvicrec.blogspot.com/2013/03/…hip-1-sc1.html
Pacman and Berzerk influences in this Mark Spaeth designed chip as part of his PhD work at MIT:
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