The
DEC 4000 AXP is a series of departmental
server computersA server is an application running on a computer that delivers a service. For example, a web server will deliver web pages when requested by a browser . The way a server and a client dialogs is called a protocol...
developed and manufactured by
Digital Equipment CorporationDigital Equipment Corporation was a pioneering American company in the computer industry. It is often referred to within the computing industry as DEC...
introduced on 10 November 1992. These systems formed part of the first generation of systems based on the
64-bit64-bit CPUs have existed in supercomputers since the 1960s and in RISC-based workstations and servers since the early 1990s. In 2003 they were introduced to the mainstream personal computer arena, in the form of the x86-64 and 64-bit PowerPC processor architectures.Without further qualification, a...
Alpha AXP architecture and at the time of introduction, ran Digital's
OpenVMS AXPOpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is the name of a high-end computer server operating system that runs on VAX, Alpha and Itanium-based families of computers...
or OSF/1 AXP
operating systemsAn operating system is an interface between hardware and user which is responsible for the management and coordination of activities and the sharing of the resources of the computer that acts as a host for computing applications run on the machine. As a host, one of the purposes of an operating...
.
The DEC 4000 AXP was succeeded by the end of 1994 by the
AlphaServerAlphaServer 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...
2000 and 2100 departmental servers.
There are two models of the DEC 4000 AXP:
- Model 6x0, code named Cobra: 160 MHz DECchip 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...
(EV4) processor(s) with 1 MB L2 cache each.
- Model 7x0, code named Fang: 190 MHz DECchip 21064 (EV4) processor(s) with 4 MB L2 cache each.
The
DEC 4000 AXP is a series of departmental
server computersA server is an application running on a computer that delivers a service. For example, a web server will deliver web pages when requested by a browser . The way a server and a client dialogs is called a protocol...
developed and manufactured by
Digital Equipment CorporationDigital Equipment Corporation was a pioneering American company in the computer industry. It is often referred to within the computing industry as DEC...
introduced on 10 November 1992. These systems formed part of the first generation of systems based on the
64-bit64-bit CPUs have existed in supercomputers since the 1960s and in RISC-based workstations and servers since the early 1990s. In 2003 they were introduced to the mainstream personal computer arena, in the form of the x86-64 and 64-bit PowerPC processor architectures.Without further qualification, a...
Alpha AXP architecture and at the time of introduction, ran Digital's
OpenVMS AXPOpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is the name of a high-end computer server operating system that runs on VAX, Alpha and Itanium-based families of computers...
or OSF/1 AXP
operating systemsAn operating system is an interface between hardware and user which is responsible for the management and coordination of activities and the sharing of the resources of the computer that acts as a host for computing applications run on the machine. As a host, one of the purposes of an operating...
.
The DEC 4000 AXP was succeeded by the end of 1994 by the
AlphaServerAlphaServer 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...
2000 and 2100 departmental servers.
Models
There are two models of the DEC 4000 AXP:
- Model 6x0, code named Cobra: 160 MHz DECchip 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...
(EV4) processor(s) with 1 MB L2 cache each.
- Model 7x0, code named Fang: 190 MHz DECchip 21064 (EV4) processor(s) with 4 MB L2 cache each. It was introduced in October 1993.
The possible values of 'x' is 1 or 2. These numbers specify the number of microprocessors in the system.
Description
The DEC 4000 AXP are two-way
symmetric multiprocessingIn computing, symmetric multiprocessing or SMP involves a multiprocessor computer architecture where two or more identical processors can connect to a single shared main memory. Most common multiprocessor systems today use an SMP architecture...
(SMP) capable systems that are housed in either a BA640 half-height cabinet or a BA641 19-inch rackmountable enclosure that contains two
backplaneA backplane is a circuit board that connects several connectors in parallel to each other, so that each pin of each connector is linked to the same relative pin of all the other connectors, forming a computer bus. It is used as a backbone to connect several printed circuit boards together to...
s, a system backplane and a storage backplane. Plugged in the system backplane were one or two CPU modules, one to four memory modules, an
I/OIn computing, input/output, or I/O, refers to the communication between an information processing system , and the outside world – possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it...
module, up to six
Futurebus+ Profile BFuturebus to a computer bus standard, intended to replace all local bus connections in a computer, including the CPU, memory, plug-in cards and even, to some extent, LAN links between machines. The effort started in 1979 and didn't complete until 1987, and then immediately went into a redesign...
modules, and in the storage backplane, were one to four fixed media mass storage compartments and one removable media mass storage compartment.
CPU module
Two models of CPU module were used in the DEC 4000 AXP, the KN430 (also known as the B2001-BA), used in the Model 600 Series, and the B2012-AA, used in the Model 700 Series. The KN430 contains a 160 MHz
DECchip 21064The 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...
microprocessorA microprocessor incorporates most or all of the functions of a central processing unit on a single integrated circuit . The first microprocessors emerged in the early 1970s and were used for electronic calculators, using binary-coded decimal arithmetic on 4-bit words...
with 1 MB of B-cache (
L2 cacheA 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...
), whereas the B2012-AA contains a 190 MHz DECchip 21064 with 4 MB of B-cache. Two C
3 (Command, Control and Communication)
ASICAn application-specific integrated circuit is an integrated circuit customized for a particular use, rather than intended for general-purpose use. For example, a chip designed solely to run a cell phone is an ASIC...
s on the CPU module provide a number of functions, such as implementing the B-cache controller and the bus interface unit (BIU), which interfaces the microprocessor to the 128-bit
addressAn address bus is a computer bus that is used to specify a physical address. When a processor or DMA-enabled device needs to read or write to a memory location, it specifies that memory location on the address bus...
and data multiplexed system bus to enable communication between the CPU, memory and I/O modules. These ASICs were fabricated in a 0.8 micrometre process.
Memory module
The MS430 memory module has capacities of 32, 64, 128, 256 and 512 MB of memory. The memory is organised into four banks, each 280 bits wide, of which 256 bits are used to store data and 24 bits are used to store error detection and correction (EDC) information. The memory is protected by EDC logic, which is capable of detecting and correcting 1-bit errors and common 2-, 3- and 4-bit errors.
The memory is implemented using 280
surface mountedSurface-mount technology is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards . Electronic devices so made are called surface-mount devices or SMDs...
dual in-line packageIn microelectronics, a dual in-line package , sometimes called a DIL package, is an electronic device package with a rectangular housing and two parallel rows of electrical connecting pins. The pins are all parallel, point downward, and extend past the bottom plane of the package at least enough...
(DIP) 4-bit
dynamic random access memoryDynamic random access memory is a type of random access memory that stores each bit of data in a separate capacitor within an integrated circuit. Since real capacitors leak charge, the information eventually fades unless the capacitor charge is refreshed periodically...
(DRAM) chips with capacities of 1, 4 and 16 Mb that reside on both sides of the module.
Located on the module are two CMIC ASICs which control the memory and interface the module to the system bus. Each CMIC ASIC is responsible for managing half of the 280-bit memory bus and the 128-bit system bus. The CMIC ASICs are fabricated in a CMOS process and are packaged in a 299-position
pin grid arrayA pin grid array, often abbreviated PGA, refers to the arrangement of pins on the integrated circuit packaging. In a PGA, the pins are arranged in a square array that may or may not cover the bottom of the package. The pins are commonly spaced 2.54 mm apart. PGAs are often mounted on printed...
(PGA) package.
The memory module is the same size as the CPU module and connects to the backplane via two 129-pin and four 24-pin connectors.
I/O module
The DEC 4000 AXP uses the KFA40 I/O module, which contains the entire I/O subsystem. The I/O module is the largest module in the system, and two variants existed. The first variant offered four
SCSI-2Small Computer System Interface, or SCSI , 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...
buses and two
EthernetEthernet is a family of frame-based computer networking technologies for local area networks . The name comes from the physical concept of the ether...
ports and the second variant offered four
DSSIThe Digital Storage Systems Interconnect is a bus developed by Digital Equipment Corporation for connecting storage devices and clustering VAX systems. It was introduced in 1988. The bus has a bandwidth of 32 Mbit/s and was typically limited to a length of 25 meters....
/SCSI buses and one Ethernet port. The second variant however only has half the bandwidth of the SCSI-2 buses of the first variant, although the advanced features of DSSI justified its use in some cases. Aside from these differences, the rest of the I/O module was essentially the same.
I/O module features common to both variants are an additional SCSI-2 bus for removable media drives only, a
ZilogZilog, Inc., often seen as ZiLOG , is a manufacturer of 8-bit, 16-bit, 24-bit, and 32-bit microprocessors, and is most famous for its Intel 8080-compatible Z80 series.-History:Zilog was incorporated in California in 1974 by Federico Faggin, who...
85C30 Serial Communications Controller (UART) that provides two
serial linesIn computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time...
, a
Dallas SemiconductorDallas Semiconductor, now a subsidiary of Maxim Integrated Products, designs and manufactures analog, digital, and mixed-signal semiconductors...
DS1287 real time clock, and most of the firmware in the DEC 4000 AXP. For controlling the Futurebus+ and to interface the I/O module to the system bus, two IONIC ASICs are used. The Ethernet functionality in the I/O function is provided by the TGEC (Third Generation Ethernet Chip), also known as the DC253, while the SCSI/DSSI buses are provided by four
NCR 53C710NCR Corporation is a technology company specializing in products for the retail, financial, travel, healthcare, food service, entertainment, gaming and public sector industries. Its main products are self-service kiosks, point-of-sale terminals, automated teller machines, check processing...
SCSI/DSSI controllers and their associated DSSI drivers (second I/O module variant only).
Most of the I/O devices are connected to the local I/O bus, known as the "Lbus", a 32-bit address and data multiplexed bus.
Storage
The DEC 4000 AXP has four fixed media mass storage compartments, each capable of holding one 5¼ inch or four 3½ inch devices. A single removable media mass storage compartment held the CD-ROM drives and tape drives. In addition to internal storage, an external storage cabinet could be attached via an external SCSI port to provide more storage.
Expansion
The DEC 4000 AXP systems used the Futurebus+ Profile B for expansion, with six slots. These slots provided a peak transfer rate of 160 MB/s.
Enclosures
The BA640 cabinet has a width of 49.9 cm (20 in), a height of 88.3 cm (35 in) and a depth of 77.5 cm (31 in). It has a maximum weight of 124 kg (275 lb). The BA641 19-inch rackmountable enclosure has a width of 48.26 cm (19 in), a height of 44.4 cm (17.5 in) and a depth of 75.7 cm (29.8 in) with mounting brackets. It has a typical weight of 65.7 kg (146 lb).