Mead & Conway’s ‘Introduction to VLSI Systems’ – The Ornamental Heraldry of Logic Gates & Shift Registers
Thursday, 27 July 2017
The gridded geometry of VSLI diagramming celebrates the cargo cult of optimum electron flow as ornamental tribal heraldry. Part modernist weaving pattern (Gunter Stolz, Annie Albers), part tribal ornamentation – its geometric constraint aesthetic is squeezed into place by the forces of functional logic and space-filling optimisation. Introduction to VLSI Systems [1978] (PDF) contains finely coloured logic gate designs, NAND & NOR op-art and hieroglyphic transistor abstractions; and offers an early description of the circuit/microchip layout problem.
The creation of a geometric script to encode a symbolic layout language might be a modern day equivalent of Islamic Girih tilings or Kilim weave patterns. But rather than floral embellishments and pointed stars of the Girih tradition, VLSI constrains the symbols for input registers, logic blocks and phase clocks to best-fit space constrained by function that is devoid of any explicit aesthetic consideration. The microchip layout problems is part of a large group of much studied topological problems – and so the design of these circuits will hold clues to the solution of their more famous sibling – The Traveling Salesman Problem – and its lesser known one – The Seven Bridges of Königsberg.
‘The task of the integrated system designer is to devise geometric shapes and their location in each of the various layers. By arranging predetermined geometric shapes on each of these layers, a system of the required function may be constructed..[ ]..A simple and common method of producing system layouts is to draw them by hand. This is typically done on a one lambda grid using the familiar colour codes to identify various system layers. One the layout has been hand drawn it can be translated into machine readable form, by encoding it into a symbolic layout language.’
Related Posts:
Microchic: Cara McCarthy’s Diagramming Microchips & Theo Kamacke’s PCB Hieroglyphics
Ulla Wiggen – Conductive Abstractions
