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System Overview
DECmpp 12000/Sx Series systems are powerful single-instruction, multiple data
(SIMD) computers, consisting of a data parallel unit (DPU), which performs
the parallel calculations, and a front-end server. The server runs the ULTRIX
operating system and functions as a scalar processor. A high-speed VMEbus
interface carries data between the DPU and the front-end server.
The DPU contains the array control unit (ACU) PCB and from 1 to 16 processor
element (PE) array PCBs. The ACU controls the PE arrays, which perform the
parallel calculations. Each PE array PCB provides 1024 processor elements. The
total collection of PE array PCBs in a system comprise the PE array.
DECmpp 12000 systems support 1, 2, 4, 8, or 16 PE array PCBs and have 15
I/O slots for optional I/O PCBs. The DPU is housed within an H9A00 series
enclosure. DECmpp 12000 systems may be ordered with either a DECsystem
5900 server or a DECstation 5000/240 server. The DECsystem 5900 is contained
within a separate H9A00 series enclosure. This configuration is illustrated in
Figure 1–1. The DECstation 5000/240 and its storage devices are contained
within two desktop boxes. This configuration is illustrated in Figure 1–2.
DECmpp 12000–LC systems support 1, 2, or 4 PE array PCBs and have 5 I/O
slots for optional I/O PCBs. The DPU is contained within a low profile cabinet
and connects to a table-top DECstation 5000 server (Figure 1–3).
Any of the DECmpp 12000/Sx/Sx system configurations may also contain an
optional Parallel Disk Array (PDA). The PDA subsystem is housed in a separate
H9A00 series enclosure.
System Overview 1–1
