SRM firmware
| Industry | Computer hardware, Software |
|---|---|
| Founded | 1957 |
| Founder | Ken Olsen, Harlan Anderson |
| Fate | Acquired by Compaq (1998) |
| Headquarters | Maynard, Massachusetts , United States |
| Products | Computers, firmware (including SRM firmware) |
The SRM firmware, also known as the SRM console, is the boot firmware created by Digital Equipment Corporation (DEC) specifically for machines utilizing the DEC Alpha microprocessor. The acronym SRM refers to the (Alpha) System Reference Manual, which outlines the architecture of Alpha AXP and the capabilities of SRM.
Originally, SRM was developed to initialize DEC's OSF/1 AXP operating system (which evolved into Digital UNIX and later Tru64 UNIX) as well as OpenVMS. Beyond these, it extends support to other operating systems such as Linux, NetBSD, OpenBSD, and FreeBSD. In contrast, Microsoft's Windows NT for Alpha platforms does not boot via SRM but employs the ARC firmware, frequently referred to as AlphaBIOS.
Certain Alpha hardware, including models like the Digital Personal Workstation, were equipped with EEPROM capable of housing both SRM and ARC firmware simultaneously. Conversely, more compact or Windows-centric devices, for example some DEC Multia models, had EEPROM storage limited to a single firmware type at any given time.
The SRM console facilitates output through graphical display adapters such as PCI-based VGA cards. If no local console is detected, it defaults to a serial interface compatible with VT100 terminals—functionality akin to the Open Firmware implemented in SPARC and Apple PowerMac systems.
Upon startup, an Alpha AXP system running SRM presents its firmware version along with a distinctive "three chevron prompt" (>>>), which allows users to input commands. These commands enable configuration of system variables that control automatic boot behavior and specify operating system parameters. SRM contains built-in drivers to support booting from SCSI hard drives, CD-ROMs on supported controllers, various IDE ATA/ATAPI devices, and also provides network boot capabilities using protocols like BOOTP or DHCP with compatible network interface cards.
When a suitable boot device is detected, SRM loads the primary bootstrap loader from the disk’s initial boot block (logical block zero) into memory and then hands over execution control to it.