8/27/2023 0 Comments Alpha bits logo![]() ![]() The group then considered hybrid systems that combined one of their existing VAX one-chip solution and a RISC chip as a coprocessor used for high-performance needs. Unfortunately, all of these approaches introduced overhead and would not be competitive with a pure-RISC machine running native RISC code. Finally, there was still the possibility of a much faster CISC processor running the complete VAX ISA. Another concept was a pure RISC system that would translate existing VAX code into its own ISA on-the-fly and store it in a CPU cache. One was a cut-down version of the VAX instruction set architecture (ISA) that would run on a RISC-like system and leave more complex VAX instructions to system subroutines. They initially considered three concepts. This led to the formation of the "RISCy VAX" team. He asked Supnik to consider what might be done with VAX to keep it competitive with future RISC systems. RISCy VAX Īs the meeting broke up, Bob Supnik was approached by Ken Olsen, who stated that the RISC chips appeared to be a future threat to their VAX line. ![]() The decision to make a VMS PRISM had already ended by this point, so there was no remaining role. When this proposal was accepted, one of the two original roles for PRISM disappeared. PRISM appeared to be faster than the R2000, but the R2000 machines could be in the market by January 1989, a year earlier than PRISM. This sparked off an acrimonious debate within the company, which came to a head in a July 1988 management meeting. After due diligence, they selected the MIPS R2000 and built a working workstation running Ultrix in a period of 90 days. Having watched the PRISM delivery date continue to slip, and facing the possibility of more delays, a team in the Palo Alto office decided to design their own workstation using another RISC processor. ![]() The plans changed again PRISM was realigned once again as a 32-bit part and aimed directly at the Unix market. The Sun-4 runs about three to four times as fast as their latest Sun-3 designs using the Motorola 68020, and any Unix offering from DEC. In October 1987, Sun Microsystems introduced the Sun-4, their first workstation using their new SPARC processor. It was not until the summer of 1987 that it was decided that it would be a 64-bit design, among the earliest such designs in a microprocessor format. Started in 1985, the PRISM design was continually changed during its development in response to changes in the computer market, leading to lengthy delays in its introduction. A new operating system named MICA would support both ULTRIX and VAX/VMS interfaces on a common kernel, allowing software for both platforms to be easily ported to the PRISM architecture. PRISM was intended to be a flexible design, supporting Unix-like applications, and Digital's existing VAX/VMS software, after minor conversion. History PRISM Īlpha emerged from an earlier RISC project named Parallel Reduced Instruction Set Machine ( PRISM), itself the product of several earlier projects. Hewlett-Packard purchased Compaq in 2002, continuing development of the existing product line until 2004, and selling Alpha-based systems, largely to the existing customer base, until April 2007. Compaq, already an Intel x86 customer, announced that they would phase out Alpha in favor of the forthcoming Hewlett-Packard/Intel Itanium architecture, and sold all Alpha intellectual property to Intel, in 2001, effectively killing the product. The Alpha architecture was sold, along with most parts of DEC, to Compaq in 1998. A port of Ultrix to Alpha was carried out during the initial development of the Alpha architecture, but was never released as a product. ![]() Operating systems that support Alpha included OpenVMS (formerly named OpenVMS AXP), Tru64 UNIX (formerly named DEC OSF/1 AXP and Digital UNIX), Windows NT (discontinued after NT 4.0 and prerelease Windows 2000 RC2), Linux ( Debian, SUSE, Gentoo and Red Hat), BSD UNIX ( NetBSD, OpenBSD and FreeBSD up to 6.x), Plan 9 from Bell Labs, and the L4Ka::Pistachio kernel. Several third-party vendors also produced Alpha systems, including PC form factor motherboards. These microprocessors are most prominently used in a variety of DEC workstations and servers, which eventually formed the basis for almost all of their mid-to-upper-scale lineup. Alpha was designed to replace 32-bit VAX complex instruction set computers (CISC) and to be a highly competitive RISC processor for Unix workstations and similar markets.Īlpha is implemented in a series of microprocessors originally developed and fabricated by DEC. Alpha (original name Alpha AXP) is a 64-bit reduced instruction set computer (RISC) instruction set architecture (ISA) developed by Digital Equipment Corporation (DEC). ![]()
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