Components Overview

Logjam basically comprises three tangible components:

The Game Board was initially designed for another project. It is a surface which can detect the position and identity of domino-like tokens: the ``blocks'' (see below). The wooden board offers 48 possible locations. The architecture of the game board is similar to the classical smart card system. Indeed, whereas RFID for instance, does not require contact or even line-of-sight to identify objects, the game board needs galvanic contact to locate the tokens⁶. For this purpose, a Motorola 6811 processor is in charge of polling, up to ten times per seconds, all 48 locations of the surface.

The Blocks are wooden tokens which are very similar to the media blocks mentioned in 2.1. Each block embedded a ``silicon serial number'' holding a 48-bits identifier. Furthermore, a copper strip on the bottom of the block is connected to the ground line of the identifier chip. When disposed on the game board, this strip initiates a galvanic contact with the board's main bus.

The Footpedals are connected to the a Sony Video Deck controlling the speed of the video play. Both pedals have two positions ``down'' and ``way down''.