DECstation
Known as the PMAX project, its focus was to produce a computer systems family with the economics and performance to compete against the likes of Sun Microsystems and other RISC-based UNIX platforms of the day.
Several architectures were considered from Intel, Motorola and others but the group quickly selected the MIPS line of microprocessors.
The (early) MIPS microprocessors supported both big- and little-endian modes (configured during hardware reset).
Little-endian mode was chosen both to match the byte ordering of VAX-based systems and the growing number of Intel-based PCs and computers.
One of the issues being debated at the project's inception was whether or not DEC could sustain, grow, and compete with an architecture it did not invent or own (manage).
The first generation of commercially marketed DEC Alpha systems, the DEC 3000 AXP series, were similar in some respects to contemporaneous MIPS-based DECstations, which were sold alongside the Alpha systems as the DECstation line was gradually phased out.
Later DECstations planned to be based on the ECL-based R6000 were canceled on 14 August 1990 after Bipolar Integrated Technology failed to deliver sufficient volumes of the microprocessor, which was difficult to fabricate.
[5] However, during a period of strategic uncertainty only weeks later in 1992, DEC appeared to abandon plans to officially provide OSF/1 on MIPS-based DECstations, instead re-emphasising ULTRIX for these models whilst intending to offer OSF/1 for the company's impending Alpha-based product lines.
The strategic confusion was blamed on power struggles within DEC, with the decision made to abandon further OSF/1 work on DECstations being attributed to an executive having gained control over the Unix workstation group, thus reportedly causing "as much of an internal uproar as it did an external one".
[9] At the end of 1992, company representatives were once again less certain about the prospects of delivering OSF/1 on the DECstation range, with the projected release in the first half of 1993 "up in the air" and under threat of being cancelled if sufficient interest were not forthcoming from software vendors.
Internally, the marketing group for the DECstation had been able to convince DEC's product strategy group that the loss in sales in failing to offer OSF/1 on the hardware would exceed the research and development costs involved in making it available, but company-wide spending cuts threatened such projects.
As the previously announced strategy had "fizzled", DEC representatives had reportedly "informed ULTRIX customers that they should start planning to move to Alpha workstations running OSF/1 in 1993", having the effect of undermining customer confidence in both the DECstation line and in ULTRIX, but also raising more serious concerns about the company's broader Unix strategy.
[12] Although introduced before DEC started to pursue a strategy based on the Advanced Computing Environment platform, the company's stated intention was that DECstation users could potentially migrate to an OSF/1-based product, potentially delivered in the form of SCO Open Desktop for the platform, offering binary compatibility with the existing ULTRIX system.
[14] However, throughout the lifespan of the Alpha design activity, it had long been envisaged that VAX and MIPS binaries would be made to run on Alpha systems, leading to the development of the mx binary translator to run ULTRIX MIPS program images on Alpha-based DEC OSF/1 systems.
Server configurations of DECstation models, distributed without a framebuffer or a graphics accelerator, both Turbochannel and Q-bus based, were called "DECsystem" but should not be confused with some PDP-10 machines of the same name.
The DECstation 5000 systems, introduced later, improved on the lack of expansion capabilities by providing the TURBOchannel Interconnect.
Initial pricing for these 5000 series models started at $3,995 for a diskless 5000/20 with 8 MB of RAM and 17-inch greyscale display.
The Personal DECstation features an integrated 8-bit color frame buffer capable of a resolution of 1024 × 768 at a refresh rate of 72 Hz.
Analog audio and ISDN support is provided by an AMD 79C30A DSC (Digital Subscriber Controller).
[28] The Model 200 Series has 15 SIMM slots located on the system module that can hold 8 to 480 MB of memory.
The memory subsystem operates at 25 MHz and is 32 bits wide to match the native word length of the R3000.
A Dallas Semiconductor DS1287 real time clock with 50 bytes of NVRAM is also featured, as is a 256 KB system boot-strap and diagnostic ROM in a socket.
In contrast, the Model 240's and 260's I/O subsystem is based around an I/O Controller ASIC that serves as a bridge between TURBOchannel and the two I/O buses it implements.
I/O devices such as the two Zilog Z85C30 SCCs (Serial Communications Controller), a NCR 53C94 ASC, an AMD 7990 LANCE, Dallas Semiconductor DS1287 real time clock and system ROM are connected to the I/O buses.
The STIC fetches the results in the FIFO and passes them on to the STAMP ASIC(s), which performs scan conversion and other graphical functions.
Audio capabilities were provided by the DECaudio TURBOchannel option module, which contained two AMD 79C30A DSC (Digital Subscriber Controller) devices and a Motorola 56001 DSP.
[citation needed] The DECspin software, introduced for the DECstation 5000 and Personal DECstation 5000 models, utilised DECmedia, DECvideo and DECaudio cards to provide videoconferencing capabilities to up to six users over a local area network and, via a DECnet router, over a dedicated long distance communications link.
[33] Confusingly, simultaneous with the launch of the DECstation workstation line, Digital also announced a range of DECstation-branded PC compatibles with Intel x86 processors that ran MS-DOS.
These were identified by three-digit model numbers; the DECstation 2xx, 3xx and 4xx series using the Intel 80286, 80386 and 80486 processors respectively.
At the time of introduction, Digital offered a trade-in program for owners of its earlier x86, but PC incompatible, computer, the Rainbow 100.
