Archaeology Magazine Archive

A publication of the Archaeological Institute of America

Special Introductory Offer!

In order to preserve the MOS Technology 6502 central processing unit, the team at Visual 6502 had to reverse engineer the chip. And, in order to do that, it had to survey it, peering beneath its packaging and dissecting and diagramming its three primary layers: its top layer of metal, its middle layer of polysilicon, and its bottom layer of silicon, which is called the "substrate."

Visual 6502 team member Greg James took on the task of "decapping" the chip (removing it from its plastic packaging) and then investigating it layer by layer, documenting what he saw as he delved deeper. To date, he's depackaged 80 different microprocessors. Here's how the process unfolds.

James Connolly, an illiterate Irish laborer and apprentice baker
Get Adobe Flash player

Nikhil Swaminathan is a senior editor at ARCHAEOLOGY.

FeatureFeature: Digging into Technology's Past