I-Machine (Ivory) Lecture at MIT, 1987
A historical lecture from MIT on the Symbolics I-Machine (Ivory) processor, detailing its VLSI implementation and architectural advancements in Lisp machine design.
"I-Machine [Ivory] Lecture at MIT, Efland & BEE 1987-09-29"
Wiki: "The Ivory family of single-chip Lisp Machine processors superseded the G-Machine 3650, 3620, and 3630 systems. The Ivory 390k transistor VLSI implementation designed in Symbolics Common Lisp using NS, a custom Symbolics Hardware Design Language (HDL), addressed a 40-bit word (8 bits tag, 32 bits data/address). Since it only addressed full words and not bytes or half-words, this allowed addressing of 4 Gigawords (GW) or 16 gigabytes (GB) of memory; the increase in address space reflected the growth of programs and data as semiconductor memory and disk space became cheaper.