The SRM firmware (also called the SRM console) is the boot

firmware In computing, firmware is a specific class of computer software that provides the low-level control for a device's specific hardware. Firmware, such as the BIOS of a personal computer, may contain basic functions of a device, and may provide h ...

written by

Digital Equipment Corporation Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president unt ...

(DEC) for computer systems based on the

DEC Alpha Alpha (original name Alpha AXP) is a 64-bit reduced instruction set computer (RISC) instruction set architecture (ISA) developed by Digital Equipment Corporation (DEC). Alpha was designed to replace 32-bit VAX complex instruction set computers ...

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...

. SRM are the initials of (Alpha) System Reference Manual, the publication detailing the Alpha AXP architecture and which specified various features of the SRM firmware. The SRM console was initially designed to boot DEC's OSF/1 AXP (later called Digital UNIX and finally Tru64 UNIX) and

OpenVMS OpenVMS, often referred to as just VMS, is a multi-user, multiprocessing and virtual memory-based operating system. It is designed to support time-sharing, batch processing, transaction processing and workstation applications. Customers using Ope ...

operating systems, although various other operating systems (such as

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

NetBSD NetBSD is a free and open-source Unix operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is a ...

OpenBSD OpenBSD is a security-focused, free and open-source, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by forking NetBSD 1.0. According to the website, the OpenBSD project em ...

, and

FreeBSD FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD), which was based on Research Unix. The first version of FreeBSD was released in 1993. In 2005, FreeBSD was the most popular ...

, for example) were also written to boot from the SRM console. The third proprietary

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

published for the Alpha AXP architecture –

Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...

Windows NT Windows NT is a proprietary graphical operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems sc ...

– did not boot from SRM; instead, Windows booted from the ARC (multi platform "Advanced RISC Computing") boot firmware. (ARC is also known as AlphaBIOS.) On many Alpha computer systems – for example, the

Digital Personal Workstation The Digital Personal Workstation, code named "sports car", is a family of entry-level to mid-range workstation computers developed and manufactured by Digital Equipment Corporation (DEC). These workstations are based on the DEC Alpha and Intel Pe ...

– both SRM and ARC could be loaded onto the

EEPROM EEPROM (also called E2PROM) stands for electrically erasable programmable read-only memory and is a type of non-volatile memory used in computers, usually integrated in microcontrollers such as smart cards and remote keyless systems, or as a ...

which held the boot firmware. However, on some smaller systems (or large systems which were never intended to boot Windows), only one of the two boot firmware variants could fit onto the EEPROM at one time. For example, the flash EEPROM of certain models of the

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 proces ...

, which was a small, personal Alpha AXP workstation designed to run Windows NT, was only large enough to hold a single firmware. The SRM console is capable of display on either a graphical adapter (such as a

PCI PCI may refer to: Business and economics * Payment card industry, businesses associated with debit, credit, and other payment cards ** Payment Card Industry Data Security Standard, a set of security requirements for credit card processors * Pro ...

VGA Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the PC industry within three years. The term can no ...

card) or, if no graphical console and/or local keyboard is detected, on a serial connection to a

VT100 The VT100 is a video terminal, introduced in August 1978 by Digital Equipment Corporation (DEC). It was one of the first terminals to support ANSI escape codes for cursor control and other tasks, and added a number of extended codes for special f ...

-compatible terminal. In this way the SRM console is similar to the

Open Firmware Open Firmware is a standard defining the interfaces of a computer firmware system, formerly endorsed by the Institute of Electrical and Electronics Engineers (IEEE). It originated at Sun Microsystems, where it was known as OpenBoot, and has bee ...

used in

SPARC SPARC (Scalable Processor Architecture) is a reduced instruction set computer (RISC) instruction set architecture originally developed by Sun Microsystems. Its design was strongly influenced by the experimental Berkeley RISC system developed ...

and

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computers, for example. Upon system initialization, an Alpha AXP computer set to boot from the SRM console displays a short report of the software version of the firmware, and presents the "three chevron prompt" consisting of three greater-than signs: Digital Personal WorkStation 433au Console V7.2-1 Mar 6 2000 14:47:02 >>> Several commands are available by typing them at the prompt, and a list of possible commands is available by entering the command help or man at the prompt. Various system variables for establishing automatic boot settings, parameter strings to be passed to an operating system and the like may also be set from the SRM prompt. The SRM firmware contains drivers for booting from boot media including SCSI hard disks and CD-ROM drives attached to a supported SCSI adapter, various IDE ATA and ATAPI devices, and network booting via

BOOTP The Bootstrap Protocol (BOOTP) is a computer networking protocol used in Internet Protocol networks to automatically assign an IP address to network devices from a configuration server. The BOOTP was originally defined in RFC 951. While some part ...

DHCP The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on Internet Protocol (IP) networks for automatically assigning IP addresses and other communication parameters to devices connected to the network using a cli ...

is possible with supported network adapters. When an appropriate disk boot device is available, the SRM console locates and loads the target primary bootstrap image using information written in the target disk boot block; in logical block zero. The boot block contains the disk location and block size of the target primary bootstrap image file, and SRM will load that into memory and will then transfer control to it.

External links

Red Hat Documentation: The SRM Firmware Console

SRM Console Reference

Alpha SRM Console for Alpha Microprocessor Motherboards User’s Guide

{{Firmware and booting SRM Firmware OpenVMS