Ralf Brown's Interrupt List (aka RBIL, x86 Interrupt List, MS-DOS Interrupt List or INTER) is a comprehensive list of interrupts, calls, hooks, interfaces, data structures, CMOS settings, memory and port addresses, as well as processor opcodes and special function registers for x86 machines from the 1981 IBM PC up to 2000 (including many clones), [1] [2] [nb 1] most of it still applying to IBM PC compatibles today.
The list covers operating systems, device drivers, and application software; both documented and undocumented information including bugs, incompatibilities, shortcomings, and workarounds, with version, locale, and date information, often at a detail level far beyond that found in the contemporary literature. [3] [4] [5] A large part of it covers system BIOSes and internals of operating systems such as DOS, OS/2, and Windows, as well as their interactions. [3] [6]
It has been a widely used resource by IBM PC system developers, [7] [4] [5] analysts, [8] as well as application programmers in the pre-Windows era. [3] [6] Parts of the compiled information have been used for and in the creation of several books on systems programming, [3] [6] [9] [10] [11] [12] some of which have also been translated into Chinese, [13] [14] [15] [6] Japanese [3] and Russian. [16] [17] As such the compilation has proven to be an important resource in developing various closed and open source operating systems, including Linux and FreeDOS. [18] Today it is still used as a reference to BIOS calls and to develop programs for DOS as well as other system-level software.
The project is the result of the research and collaborative effort of more than 650 listed contributors worldwide over a period of 15 years, of which about 290 provided significant information (and some 55 of them even more than once). [1] The original list was created in January 1985 by Janet Jack and others, [19] and, named "Interrupt List for MS-DOS", it was subsequently maintained and mailed to requestors on Usenet by Ross M. Greenberg until 1986. [20] [21] [22] Since October 1987 it is maintained by Ralf D. Brown, [23] a researcher at Carnegie Mellon University's Language Technologies Institute. [3] [6] [24] Information from several other interrupt listings was merged into the list in order to establish one comprehensive reference compilation. Over the years, Michael A. Shiels, Timothy Patrick Farley, Matthias R. Paul, Robin Douglas Howard Walker, Wolfgang Lierz and Tamura Jones became major contributors to the project, providing information all over the list. [1] The project was also expanded to include other PC development-related information and therefore absorbed a number of independently maintained lists on PC I/O ports (by Wim Osterholt and Matthias R. Paul), BIOS CMOS memory contents (by Atley Padgett Peterson), processor opcodes (by Alex V. Potemkin) and bugs (by Harald Feldmann). [1] [nb 1] Brown and Paul also conducted several systematic surveys on specific hard- and software details among a number of dedicated user groups in order to validate some info and to help fill some gaps in the list. [25] [26] [27]
Originally, the list was distributed in an archive named INTERRUP in various compression formats as well as in the form of diffs. The distribution file name was changed to include a version in the form INTERnyy (with n = issue number, and yy = 2-digit release year) in 1988. In mid 1989 the distribution settled to only use ZIP compression. [28] When the archive reached the size of a 360 KB floppy in June 1991, the distribution split into several files following an INTERrrp.ZIP naming scheme (with rr = revision starting with 26 for version 91.3, and p = part indicator of the package starting with letter A). Officially named "MS-DOS Interrupt List" and "x86 Interrupt List" (abbreviated as "INTER") by its maintainer, the community coined the unofficial name "Ralf Brown's Interrupt List" (abbreviated as "RBIL") in the 1990s.
The publication is currently at revision 61 as of 17 July 2000 with almost 8 MB of ASCII text including close to 9600 entries plus about 5400 tables, [1] fully cross linked, which would result in more than 3700 pages (at 60 lines per page) of condensed information when printed. Of this, the interrupt list itself makes up some 5.5 MB for more than 2500 pages printed. [nb 1]
While the project is not officially abandoned and the website is still maintained (as of 2023 [update] ), new releases have not been forthcoming for a very long time, despite the fact that information was still pending for release even before the INTER61 release in 2000. [29] New releases were planned for at several times in 2001 [30] [31] and 2002, [32] [33] [34] [35] [26] [27] but when they did not materialize, portions of the new information on DOS and PC internals provided by Paul were circulated in preliminary form in the development community for peer-review and to assist in operating system development. [31] [36] [37] [33] [38] [39] [40] [41] [26] [42] [43] [44] [45]
INTERRUP.LST 5.700.679 bytes, 151.173 lines FARCALL.LST 81.446 bytes, 2.178 lines MEMORY.LST 144.149 bytes, 3.606 lines PORTS.LST 879.133 bytes, 23.893 lines CMOS.LST 77.175 bytes, 2.015 lines I2C.LST 141.061 bytes, 3.563 lines OPCODES.LST 624.174 bytes, 33.936 lines MSR.LST 81.345 bytes, 2.190 lines SMM.LST 7.939 bytes, 291 lines 86BUGS.LST 119.004 bytes, 3.004 lines 7.856.105 bytes, 225.849 lines
DR-DOS is a disk operating system for IBM PC compatibles. Upon its introduction in 1988, it was the first DOS attempting to be compatible with IBM PC DOS and MS-DOS.
The Hercules Graphics Card (HGC) is a computer graphics controller formerly made by Hercules Computer Technology, Inc. that combines IBM's text-only MDA display standard with a bitmapped graphics mode, also offering a parallel printer port. This allows the HGC to offer both high-quality text and graphics from a single card.
The A20, or address line 20, is one of the electrical lines that make up the system bus of an x86-based computer system. The A20 line in particular is used to transmit the 21st bit on the address bus.
In DOS memory management, the high memory area (HMA) is the RAM area consisting of the first 65520 bytes above the one megabyte in an IBM AT or compatible computer.
In compiler theory, dead-code elimination is a compiler optimization to remove dead code. Removing such code has several benefits: it shrinks program size, an important consideration in some contexts, and it allows the running program to avoid executing irrelevant operations, which reduces its running time. It can also enable further optimizations by simplifying program structure. Dead code includes code that can never be executed, and code that only affects dead variables, that is, irrelevant to the program.
Star Trek is the code name that was given to a secret prototype project, running a port of Macintosh System 7 and its applications on Intel-compatible x86 personal computers. The project, starting in February 1992, was conceived in collaboration between Apple Computer, who provided the majority of engineers, and Novell, who at the time was one of the leaders of cross-platform file-servers. The plan was that Novell would market the resulting OS as a challenge to Microsoft Windows, but the project was discontinued in 1993 and never released, although components were reused in other projects. The project was named after the Star Trek science fiction franchise with the slogan "To boldly go where no Mac has gone before".
.exe is a common filename extension denoting an executable file for Microsoft Windows, OS/2, and DOS.
A fat binary is a computer executable program or library which has been expanded with code native to multiple instruction sets which can consequently be run on multiple processor types. This results in a file larger than a normal one-architecture binary file, thus the name.
In x86 computing, unreal mode, also big real mode, flat real mode, or voodoo mode is a variant of real mode, in which one or more segment descriptors has been loaded with non-standard values, like 32-bit limits allowing access to the entire memory. Contrary to its name, it is not a separate addressing mode that the x86 processors can operate in. It is used in the 80286 and later x86 processors.
The Program Segment Prefix (PSP) is a data structure used in DOS systems to store the state of a program. It resembles the Zero Page in the CP/M operating system. The PSP has the following structure:
In computing, the BIOS parameter block, often shortened to BPB, is a data structure in the volume boot record (VBR) describing the physical layout of a data storage volume. On partitioned devices, such as hard disks, the BPB describes the volume partition, whereas, on unpartitioned devices, such as floppy disks, it describes the entire medium. A basic BPB can appear and be used on any partition, including floppy disks where its presence is often necessary; however, certain filesystems also make use of it in describing basic filesystem structures. Filesystems making use of a BIOS parameter block include FAT12, FAT16, FAT32, HPFS, and NTFS. Due to different types of fields and the amount of data they contain, the length of the BPB is different for FAT16, FAT32, and NTFS boot sectors. Combined with the 11-byte data structure at the very start of volume boot records immediately preceding the BPB or EBPB, this is also called FDC descriptor or extended FDC descriptor in ECMA-107 or ISO/IEC 9293.
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Long filename (LFN) support is Microsoft's backward-compatible extension of the 8.3 filename naming scheme used in DOS. Long filenames can be more descriptive, including longer filename extensions such as .jpeg
, .tiff
, .html
, and .xhtml
that are common on other operating systems, rather than specialized shortened names such as .jpg
, .tif
, .htm
, or .xht
. The standard has been common with File Allocation Table (FAT) filesystems since its first implementation in Windows NT 3.5 of 1994.
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.sys is a filename extension used in MS-DOS applications and Microsoft Windows operating systems. They are system files that contain device drivers or hardware configurations for the system.
Computer hardware or software is said to be bug compatible if it exactly replicates even an undesirable feature of a previous version. The phrase is found in the Jargon File.
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DOS Protected Mode Services (DPMS) is a set of extended DOS memory management services to allow DPMS-enabled DOS drivers to load and execute in extended memory and protected mode.
Control-Alt-Delete is a computer keyboard command on IBM PC compatible computers, invoked by pressing the Delete key while holding the Control and Alt keys: Ctrl+Alt+Delete. The function of the key combination differs depending on the context but it generally interrupts or facilitates interrupting a function. For instance, in pre-boot environment or in MS-DOS, Windows 3.0 and earlier versions of Windows or OS/2, the key combination reboots the computer. Starting with Windows 95, the key combination invokes a task manager or security related component that facilitates ending a Windows session or killing a frozen application.
In computing, a hardware code page (HWCP) refers to a code page supported natively by a hardware device such as a display adapter or printer. The glyphs to present the characters are stored in the alphanumeric character generator's resident read-only memory and are thus not user-changeable. They are available for use by the system without having to load any font definitions into the device first. Startup messages issued by a PC's System BIOS or displayed by an operating system before initializing its own code page switching logic and font management and before switching to graphics mode are displayed in a computer's default hardware code page.
An enormous listing of DOS and BIOS interrupt calls, many undocumented and program-specific. Quite simply, some of Snooper's reports wouldn't be there without it. Very useful in that it reports bugs and incompatibilities books rarely mention. And it's free!
Ralf Brown maintains an astounding file which is chock-full of detailed, absolutely-indispensable information for DOS programmers on Hardware, BIOS, DOS, and other interrupts. […] You should not be without this file, which is widely-known as "Ralf Brown's Interrupt List". Ask about it. You will find it."
A cornucopia of descriptions of interrupt and function calls on the IBM PC. A great thing to have on your hard disk if you don't have a Ray Duncan or Peter Norton book handy.(NB. About the 1988-01-30 version (73728 bytes) of the interrupt list.)
In the past, the Ralf Brown interrupt list was the Bible of DOS virus analysis.