DEC 2000 AXP
Encyclopedia
The DECpc AXP 150, code-named Jensen, is an entry-level workstation
developed and manufactured by Digital Equipment Corporation
. Introduced on 25 May 1993, the DECpc AXP 150 was the first Alpha
-based system to support the Windows NT
operating system
and the basis for the DEC 2000 AXP entry-level servers. It was discontinued on 28 February 1994, succeeded by the entry-level Multia
and the entry-level and mid-range models of the AlphaStation
family. The charter for the development and production of the DEC 2000 AXP was held by Digital's Entry Level Solutions Business, based in Ayr
, Scotland
.
and OSF/1 AXP (later renamed to Digital UNIX) operating systems and support for a VT-series terminal
or equivalent. The DEC 2000 AXP family succeeded by the AlphaServer 1000
. There are two models in the DEC 2000 AXP family: the Model 300 and Model 500.
microprocessor with an external 512 KB B-cache (L2 cache
), which is implemented with 17 nanosecond SRAMs
located on the motherboard.
The 128-bit memory subsystem supports 16 to 128 MB of memory. Standard 36-bit, 70 nanosecond SIMMs with longword parity
protection are used to populate eight SIMM
slots, which are organised in two banks of four slots each. The DEC 2000 AXP supports two memory options, a 16 MB (4 × 4 MB SIMMs) and a 64 MB (4 × 16 MB SIMMs) memory kit.
The DECpc AXP 150 has six EISA slots for expansion. Pre-installed EISA cards typically comprised a Compaq
QVision VGA adapter, Adaptec
AHA-1742 SCSI
host adapter, and a DEC DE422 Ethernet
adapter. The DECpc AXP 150 running Windows NT was intended to be used as a workstation and therefore can only use a VGA
monitor.
Unlike other similar Alpha systems from Digital at the time, such as the DEC 3000 AXP
, the DECpc AXP 150 used the EISA
bus for expansion instead of the TURBOchannel
interconnect. The decision to use the EISA bus was due to cost requirements. The EISA bus was an industry standard bus, and there were more vendors offering EISA options, in addition to EISA chipsets. In contrast, the TURBOchannel bus, while offering higher performance, would have required more expensive ASICs to implement like the DEC 3000 AXP, and would have reduced the number of third-party options available.
Because the DECchip 21064's signalling is incompatible with the EISA chipset and the system peripherals, the DECchip signals are interfaced to two buses, an address and command bus and a 32-bit data bus that masquerades as the 80486 interfaces. These two buses are referred to as "pseudo-486". The EISA bus itself was implemented by a subset of the Intel 82350DT chipset. The 82358 EBC (EISA Bus Controller) chip and 82357 ISP (Integrated System Peripheral) chip implements the EISA bus and provides it with an interface to the system. Two 82352 EBB (EISA Bus Buffer) chips are also present, with one used to interface the EISA bus to a 32-bit pseudo-486 data bus, and the other used to interface the EISA bus to a pseudo-486 address and command bus.
This arrangement of buffering and converting buses and control signals resulted in an inefficient I/O subsystem and as a result, the EISA bus only achieved a peak bandwidth of 25 MB/s (compared to 33 MB/s in standard PCs).
A VLSI Technologies
VL82C106 combination chip, connected to the pseudo-486 buses, contains the real time clock and 66 bytes of battery-backed RAM, in addition to two serial
line interfaces, a LPT
interface and two PS/2
port interfaces. The real time clock and the battery-backed RAM draws power from an external 4.5 volt battery pack. The battery-backed RAM was primarily used to store system configuration information.
Workstation
A workstation is a high-end microcomputer designed for technical or scientific applications. Intended primarily to be used by one person at a time, they are commonly connected to a local area network and run multi-user operating systems...
developed and manufactured by Digital Equipment Corporation
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
. Introduced on 25 May 1993, the DECpc AXP 150 was the first Alpha
DEC Alpha
Alpha, originally known as Alpha AXP, is a 64-bit reduced instruction set computer instruction set architecture developed by Digital Equipment Corporation , designed to replace the 32-bit VAX complex instruction set computer ISA and its implementations. Alpha was implemented in microprocessors...
-based system to support the Windows NT
Windows NT
Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
and the basis for the DEC 2000 AXP entry-level servers. It was discontinued on 28 February 1994, succeeded by the entry-level Multia
DEC Multia
The Multia, later re-branded the Universal Desktop Box, was a line of desktop computers introduced by Digital Equipment Corporation on 7 November 1994. The line is notable in that units were offered with either an Alpha AXP or Intel Pentium processor as the CPU, and most hardware other than the...
and the entry-level and mid-range models of the AlphaStation
AlphaStation
AlphaStation was the name given to a series of computer workstations, produced from 1994 onwards by Digital Equipment Corporation, and latterly by Compaq and HP. As the name suggests, the AlphaStations were based on the DEC Alpha 64-bit microprocessor...
family. The charter for the development and production of the DEC 2000 AXP was held by Digital's Entry Level Solutions Business, based in Ayr
Ayr
Ayr is a town and port situated on the Firth of Clyde in south-west Scotland. With a population of around 46,000, Ayr is the largest settlement in Ayrshire, of which it is the county town, and has held royal burgh status since 1205...
, Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
.
DEC 2000 AXP
The DEC 2000 AXP family are entry-level servers based on the DECpc AXP 150. Differences were support for Digital's OpenVMS AXPOpenVMS
OpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...
and OSF/1 AXP (later renamed to Digital UNIX) operating systems and support for a VT-series terminal
Computer terminal
A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system...
or equivalent. The DEC 2000 AXP family succeeded by the AlphaServer 1000
AlphaServer
AlphaServer was the name given to a series of server computers, produced from 1994 onwards by Digital Equipment Corporation, and latterly by Compaq and HP. As the name suggests, the AlphaServers were based on the DEC Alpha 64-bit microprocessor...
. There are two models in the DEC 2000 AXP family: the Model 300 and Model 500.
Model 300
The DEC 2000 Model 300 AXP, code-named Jensen, is identical to the DECpc AXP 150 but was intended to be used as a server. Some options available for the DECpc AXP 150 are not available for the Model 300. It was introduced on 12 October 1993, and was discontinued on 28 February 1994.Model 500
The DEC 2000 Model 500 AXP, code-named Culzean, was marketed as a server running either Windows NT Advanced Server, DEC OSF/1 AXP or OpenVMS. Introduced on 15 November 1993, the Model 500 was similar to the Model 300, but housed in a larger pedestal-type enclosure capable with space for up to 12 3.5 in hard disks and incorporating an Intelligent Front Panel (IFP) for system monitoring and control. The Model 500 also supported either two 415 W power supplies or one power supply plus a battery Standby Power Supply (SPS). It was discontinued on 30 December 1994.Description
The DECpc AXP 150 systems used a 150 MHz DECchip 21064Alpha 21064
The Alpha 21064 is a microprocessor developed and fabricated by Digital Equipment Corporation that implemented the Alpha instruction set architecture . It was introduced as the DECchip 21064 before it was renamed in 1994. The 21064 is also known by its code name, EV4...
microprocessor with an external 512 KB B-cache (L2 cache
CPU cache
A CPU cache is a cache used by the central processing unit of a computer to reduce the average time to access memory. The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations...
), which is implemented with 17 nanosecond SRAMs
Static random access memory
Static random-access memory is a type of semiconductor memory where the word static indicates that, unlike dynamic RAM , it does not need to be periodically refreshed, as SRAM uses bistable latching circuitry to store each bit...
located on the motherboard.
The 128-bit memory subsystem supports 16 to 128 MB of memory. Standard 36-bit, 70 nanosecond SIMMs with longword parity
Parity bit
A parity bit is a bit that is added to ensure that the number of bits with the value one in a set of bits is even or odd. Parity bits are used as the simplest form of error detecting code....
protection are used to populate eight SIMM
SIMM
A SIMM, or single in-line memory module, is a type of memory module containing random access memory used in computers from the early 1980s to the late 1990s. It differs from a dual in-line memory module , the most predominant form of memory module today, in that the contacts on a SIMM are redundant...
slots, which are organised in two banks of four slots each. The DEC 2000 AXP supports two memory options, a 16 MB (4 × 4 MB SIMMs) and a 64 MB (4 × 16 MB SIMMs) memory kit.
The DECpc AXP 150 has six EISA slots for expansion. Pre-installed EISA cards typically comprised a Compaq
Compaq
Compaq Computer Corporation is a personal computer company founded in 1982. Once the largest supplier of personal computing systems in the world, Compaq existed as an independent corporation until 2002, when it was acquired for US$25 billion by Hewlett-Packard....
QVision VGA adapter, Adaptec
Adaptec
Adaptec is a computer hardware brand owned by PMC-Sierra that is used on some of its host adapters for connecting storage devices to computers. The production line of Adaptec is in Indonesia. Products are made to interface with SCSI, Serial ATA, and Serial attached SCSI. Some of its host adapters...
AHA-1742 SCSI
SCSI
Small Computer System Interface is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, and electrical and optical interfaces. SCSI is most commonly used for hard disks and tape drives, but it...
host adapter, and a DEC DE422 Ethernet
Ethernet
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
adapter. The DECpc AXP 150 running Windows NT was intended to be used as a workstation and therefore can only use a VGA
Video Graphics Array
Video Graphics Array refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, but through its widespread adoption has also come to mean either an analog computer display standard, the 15-pin D-subminiature VGA connector or the 640×480 resolution...
monitor.
Unlike other similar Alpha systems from Digital at the time, such as the DEC 3000 AXP
DEC 3000 AXP
DEC 3000 AXP was the name given to a series of computer workstations and servers, produced from 1992 to around 1995 by Digital Equipment Corporation. The DEC 3000 AXP series formed part of the first generation of computer systems based on the 64-bit Alpha AXP architecture...
, the DECpc AXP 150 used the EISA
Extended Industry Standard Architecture
The Extended Industry Standard Architecture is a bus standard for IBM PC compatible computers...
bus for expansion instead of the TURBOchannel
TURBOchannel
TURBOchannel is an open computer bus developed by DEC by during the late 1980s and early 1990s. Although it was open for any vendor to implement in their own systems, it was mostly used in Digital's own systems such as the MIPS-based DECstation and DECsystem systems, in the VAXstation 4000, and in...
interconnect. The decision to use the EISA bus was due to cost requirements. The EISA bus was an industry standard bus, and there were more vendors offering EISA options, in addition to EISA chipsets. In contrast, the TURBOchannel bus, while offering higher performance, would have required more expensive ASICs to implement like the DEC 3000 AXP, and would have reduced the number of third-party options available.
Because the DECchip 21064's signalling is incompatible with the EISA chipset and the system peripherals, the DECchip signals are interfaced to two buses, an address and command bus and a 32-bit data bus that masquerades as the 80486 interfaces. These two buses are referred to as "pseudo-486". The EISA bus itself was implemented by a subset of the Intel 82350DT chipset. The 82358 EBC (EISA Bus Controller) chip and 82357 ISP (Integrated System Peripheral) chip implements the EISA bus and provides it with an interface to the system. Two 82352 EBB (EISA Bus Buffer) chips are also present, with one used to interface the EISA bus to a 32-bit pseudo-486 data bus, and the other used to interface the EISA bus to a pseudo-486 address and command bus.
This arrangement of buffering and converting buses and control signals resulted in an inefficient I/O subsystem and as a result, the EISA bus only achieved a peak bandwidth of 25 MB/s (compared to 33 MB/s in standard PCs).
A VLSI Technologies
VLSI Technology
VLSI Technology, Inc was a company which designed and manufactured custom and semi-custom ICs. The company was based in Silicon Valley, with headquarters at 1109 McKay Drive in San Jose, California...
VL82C106 combination chip, connected to the pseudo-486 buses, contains the real time clock and 66 bytes of battery-backed RAM, in addition to two serial
Serial port
In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time...
line interfaces, a LPT
LPT
LPT is the original, and still common, name of the parallel port interface on IBM PC-compatible computers. It was designed to operate a text printer that used IBM's 8-bit extended ASCII character set. The name derives from the fact that "line printer" was a common generic term at the time for any...
interface and two PS/2
PS/2 connector
The PS/2 connector is a 6-pin Mini-DIN connector used for connecting some keyboards and mice to a PC compatible computer system. Its name comes from the IBM Personal System/2 series of personal computers, with which it was introduced in 1987...
port interfaces. The real time clock and the battery-backed RAM draws power from an external 4.5 volt battery pack. The battery-backed RAM was primarily used to store system configuration information.