\noindent {\bf Active Memory Technology DAP } \noindent {\bf Bit Parallel Architecture } \vspace {.1in} \noindent {\bf Architecture:} The AMT DAP is an SIMD lockstep machine which operates on multiple data one bit at a time. It can support, via software, variable-length arithmetic. Configuration is a grid of processing elements with nearest neighbour connections and row/column data highways. The row/column data highways allow efficient global fetches and broadcasts giving the system the properties of associative processors. \vspace {.1in} \noindent The major differences over the ILLIAC IV are: \begin{tabbing} aaa\= \kill \> bit processors \\ \> row/column highway \\ \> much larger memory per processor \\ \> high input/output capability \end{tabbing} \vspace {.1in} \noindent AMT offers two models of the DAP. The DAP 510 is a 32 x 32 array of processors, and the DAP 610 is a 64 x 64 array of processors. The DAP array is constructed using custom CMOS VLSI chips which contain 64 processor elements. Both models of the DAP currently operate with a 100 nsec cycle time. A real-time graphic display interface is available for the DAP systems. The following table summarizes the characteristics of the two DAP models. \vspace {.1in} \noindent The development environment (cross-compilers and run time debugging aids) are supplied running under UNIX. The DAP is linked as a peripheral via a 1.5 Mbyte/sec parallel interface. \begin{center} \begin{tabular}{l l l l l} Model & Memory & I/O Data & Processing & Memory \\ & Bandwidth & Rate & Elements & Configurations \\ \hline DAP 510 & 1.2 Gbytes/sec & 50 Mbytes/sec & 1024 & 4, 8, 16 Mbytes \\ DAP 610 & 4.8 Gbytes/sec & 100 Mbytes/sec & 4096 & 16, 32, 64 Mbytes \end{tabular} \end{center} \vspace {.1in} \noindent {\bf Configuration:} The DAP 510 is small enough to fit under a desk, while the DAP 610 is housed in a standard EIA rack cabinet. Both DAP models can be hosted by Sun or DEC VAX computers and workstations. The DAP can be connected to a Sun host via the SCSI interface. Connection to DEC VAX systems is via DR11W or DRB32 interfaces. Connection to the Aptec IOC is supported as well as direct connection to VME bus. \newpage \begin{center} \begin{tabular}{l l l l} & DAP 510 & DAP 610 \\ \hline Array size & 32 x 32 & 64 x 64 & \\ Array memory & 8 Mbytes & 16 Mbytes & (max. of 128 or 512 Mbytes) \\ Code store & 512 Kbytes & 512 Kbytes & (max. of 4 Mbytes) \\ Instruction rate & 10 MHz & 10 MHz & \\ host & Sun or VAX & Sun or VAX & \\ Size & 17 x 13 x 20 in. & 45 x 25 x 38 in. & \\ Price & \$155,000 & \$320,000 & \\ \end{tabular} \end{center} \vspace{.1in} \noindent {\bf Software and Languages Available:} The principal programming language used is Fortran plus, an augmented Fortan that includes most of the array features proposed for Fortran 8X. APAL, an assembler language, is also available. \vspace{.1in} \noindent {\bf Applications:} The variable length arithmetic capabilities of the DAP make it particularly well adapted to large scale signal and image processing applications. \vspace {.1in} \noindent AMT provides libraries of algorithms in subroutine form to support image and signal processing application development. A general-purpose algorithm library is also available. Major application areas include scientific and engineering computing, image processing, signal processing, defense applications, and database applications. \vspace {.1in} \noindent The present DAP systems are third-generation machines which started with a 64 x 64 array originally installed at QMC (Queen Mary College, University of London). The QMC machine, which had an effective cycle time of 250 nsec, proved highly adaptable to a wide range of numerical problems based on partial differential equations. The performance on large-scale Monte Carlo simulations in lattice gauge theory and molecular dynamics was found to be exceptional and, in some specialized applications such as the Ising model, the DAP outperformed a CRAY-1 by a factor of 10. \vspace {.1in} \noindent {\bf Status:} Initial shipments of the DAP 510 began in February 1988. Shipments of the DAP 610 began in November 1988. At year end of 1988, 60 DAP 510 and 5 DAP 610 machines were installed in the United States and Europe. \vspace {.1in} \noindent {\bf Contact:} \begin{flushleft} Dr Geoff Manning\\ Active Memory Technology Limited\\ 65 Suttons Park Avenue\\ Reading RG6 1AZ\\ 0734-661111\\ \vspace {.1in} Chief Technical Officer: Dennis Parkinson\\ \newpage Bill Terry\\ Active Memory Technology Inc.\\ 16802 Aston Street Suite 103\\ Irvine, CA 92714\\ 714-261-8901 \end{flushleft} .