System Reference Manual

The SRM firmware (also called the SRM console) is the boot firmware written by Digital Equipment Corporation (DEC) for computer systems based on the Alpha AXP microprocessor. The acronym SRM is derived from the phrase 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 operating systems, although various other operating systems (such as Linux, NetBSD, OpenBSD, and FreeBSD, for example) were also written to boot from the SRM console. The third proprietary operating system published for the Alpha AXP architecture – Microsoft Windows NT – 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 – both SRM and ARC could be loaded onto the EEPROM 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 the DEC Multia, 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 VGA card) or, if no graphical console and/or local keyboard is detected, on a serial connection to a VT100-compatible terminal. In this way the SRM console is similar to the Open Firmware used in SPARC and Apple PowerMac computers, for example.

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