Personal Iris: The 4D/30 and 4D/35

Using the latest microprocessor from MIPS Computer Systems and advanced VLSI gate arrays, Silicon Graphics has redesigned the Personal IRIS CPU architecture. Built to support release 3.3 of Silicon Graphics' system software, the 4D/30 and 4D/35 offer a broad range of performance enhancements while providing a completely compatible upgrade path for existing Personal IRIS systems.

Increased Overall System Performance

The 4D/30 and 4D/35 incorporate MIPS Computer Systems R3000A CPU and R3000 FPU into the Personal IRIS product family. The 4D/30 uses a 30MHz R3000A CPU and the 4D/35 uses a 35MHz R3000A CPU. The fast CPU clock rate is complemented by a fast system bus (increased from 10MHz to 30MHz), an innovative memory subsystem, and expanded peripheral I/O capabilities. These features combine to deliver the highest available R3000 uniprocessor performance.

New CPU Architecture

The 4D/30 and 4D/35 offer full support for the R3000A feature set, including block cache refills, instruction streaming and partial cache writes. Additionally, a multi-level CPU write buffer (resident on a Silicon Graphics proprietary VLSI gate array) significantly enhances CPU write throughput and maximizes MFLOP performance. Overall CPU cache size has been increased to 64K instruction and 64K data. The fastest members of the Personal IRIS family, the 4D/30 is rated at 27 MIPS (VAX Dhrystone) and 4.7 MFLOPS (double precision), and the 4D/35 is rated at 33 MIPS and 6 MFLOPS.

Enhanced High-Speed Memory

The 4D/30 and 4D/35 offer users access to 128MB of very high throughput main memory. An innovative memory architecture results in an order-of-magnitude increase in memory bandwidth over previous Personal IRIS systems. This enhancement, added to the R3000A implementation, faster system bus and expanded I/O capabilities, significantly improves application performance.

Memory is user installable and available from a minimum of 8MB, up to a maximum of 128MB.

Greater I/O Bandwidth

Peripheral management is handled through a highly integrated peripheral controller. A Motorola digital signal processor (DSP) controls the audio interface.

The peripheral controller has a FIFO buffer for each of four independent channels. The buffers accumulate data from slow peripherals and transfer it directly into main memory. A burst mode transfer scheme allows data to be moved with very low system bus overhead. As a result, raw peripheral performance is increased and the impact of peripherall interactions on the main processor is minimized. High rates of peripheral activity can be achieved with no impact on computational or graphics performance.

The DSP processes audio signals and handles data transfers through four serial channels. This design also relieves the interrupt demand on the main processor. All four serial channels can operate at speeds up to 38.4Kbaud.

Expanded I/O Capability

In addition to the Ethernet, parallel, VME, and two RS232 interfaces available on the 4D/25, the 4D/30 and 4D/35 offer two DIN-connector serial ports.

Digital audio I/O based on the AES3 serial digital interface is optional on the 4D/30 and available on the 4D/35. These new I/O capabilities provide the user access to a whole range of new peripherals and communications options.

Specifications

                   4D/25               4D/30               4D/35 and 4D/35S

Processor          RISC 20MHz          RISC 30MHz          RISC 35MHz       

MIPS               16                  27                  33

MFLOPS             1.6                 4.7                 6.0

SPECmark           14                  25.4                31.1

Cache              32KB/64KB d/i       64KB/64KB d/i       64KB/64KB d/i

Memory Size        8 - 32MB            8 - 128MB           8 - 128MB

VME                single-word data    block-transfer      block-transfer
                   transfer only       mode supported      mode supported

Parallel           output only         bi-directional      bi-directional
                                       data transfer       data transfer
                                       (optional)

Audio              basic analog        analog and serial   analog and serial
                   I/O, 8bit           digital, 16bit      digital, 16bit
                   precision mono      precision stereo    precision stereo

For more information please call:

U.S. 1(800) 800-7441
Europe (41) 22-798.75.25
North Pacific (81) 3-5420.71.10

South Pacific (61) 2-879.95.00
Latin America 1(415) 390.46.37
Canada 1(416) 625-4747

Silicon Surf - World Wide Web Server

URL: http://www.sgi.com/

Corporate Office

2011 N. Shoreline Boulevard
Mountain View, CA 94043
(415) 960-1980

Specifications subject to change without notice. Silicon Graphics, the Silicon Graphics logo and IRIS are registered trademarks, and Personal IRIS is a trademark of Silicon Graphics, Inc.; Motorola is a registered trademark of Motorola, Inc. Copyright 1991, Silicon Graphics, Inc. All rights reserved.