S. Waldschmidt

GCA: Global Cellular Automata. A Flexible Parallel Model

A model called global cellular automata (GCA) will be introduced. The new model preserves the good features of the cellular automata but overcomes its restrictions. In the GCA the cell state consists of a data field and additional pointers. Via these pointers, each cell has read access to any other cell in the cell field, and the pointers may be changed from generation to generation. Compared to the cellular automata the neighbourhood is dynamic and differs from cell to cell. For many applications parallel algorithms can be found straight forward and can directly be mapped on this model. As the model is also massive parallel in a simple way, it can efficiently be supported by hardware.

A Stream Processor Architecture Based on the Configurable CEPRA-S

Stream processing is a very efficient method to process large amounts of data. In contrast to vector architectures, stream processing involves instruction stream which are associated with data streams instead of a single instruction operating on data streams (vectors) thus facilitating individual processing of stream elements. Furthermore, operators in the arithmetic/logic unit can be configured to meet special processing requirements of an application. In the following article an architecture which can be configured as a stream processor is described.

CDL++ for the Description of Moving Objects in Cellular Automata

We introduce a new model for objects which can move around on a cellular grid. The model consists of two phases, the movement phase and the conflict resolution phase. In the movement part of the description objects specify their desired direction. The conflict, which occurs when alternative objects want to move to the same free cell, is resolved in the conflict resolution part. The cellular description language CDL was extended to CDL++ in order to describe moving objects. This extension is automatically converted into a two-phased CDL program.

The Cellular Processor Architecture CEPRA-1X and Its Configuration by CDL

The configurable coprocessor CEPRA-1X was developed as a PC plug-in card in order to speed up cellular processing significantly. Cellular Processing is an attractive and simple massive parallel processing model. To increase its general acceptance and usability it must be supported by a software environment, an efficient simulator and a special language. For this purpose the cellular description language CDL was defined and implemented. With CDL complex cellular algorithms can be described in a concise and readable form. A CDL program can automatically be transformed into a logical design for the CEPRA-1X. The design is loaded into field programmable gate arrays for the computation of the state transition of the cells. For time dependent or complex rules the design may be reconfigured between consecutive generations. An example is presented to show the generation of logic code.

The Cells Start Walking: Moving Objects in CDL++

We introduce a new model and a description for objects which can move around on a cellular grid. In the movement part of the model the objects specify the direction in which they want to move. The conflict, which occurs when objects collide or when alternative objects want to move to the same free cell, is resolved through the conflict resolution part of the model. We present an extension to the cellular description language CDL which implements the moving objects and we give example programs. This extension CDL++ is automatically converted into a two-phased CDL program.