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Booting

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169: 708:(released first in 1975) and an even earlier, similar machine (based on the Intel 8008 CPU) had no bootstrapping hardware as such. When powered-up, the CPU would see memory that would contain random data. The front panels of these machines carried toggle switches for entering addresses and data, one switch per bit of the computer memory word and address bus. Simple additions to the hardware permitted one memory location at a time to be loaded from those switches to store bootstrap code. Meanwhile, the CPU was kept from attempting to execute memory content. Once correctly loaded, the CPU was enabled to execute the bootstrapping code. This process, similar to that used for several earlier minicomputers, was tedious and had to be error-free. 2055:
problems, relating to project organization, project control and product quality. Many processes will become distributed as well. The defect detection process, so important for measuring and eventually achieving product quality, is typically one of the first to experience problems caused by the distributed nature of the project. The distribution of defect detection activities over several parties introduces risks like the inadequate review of work products, occurrence of "blind spots" with respect to test coverage or over-testing of components. Lifecycle-wide coordination of defect detection is therefore needed to ensure effectiveness and efficiency of defect detection activities. —J.J.M. Trienekens; R.J. Kusters. (2004)
1890:. Such an interface may be used to write the boot loader program into bootable non-volatile memory (e.g. flash) by instructing the processor core to perform the necessary actions to program non-volatile memory. Alternatively, the debug interface may be used to upload some diagnostic or boot code into RAM, and then to start the processor core and instruct it to execute the uploaded code. This allows, for example, the recovery of embedded systems where no software remains on any supported boot device, and where the processor does not have any integrated boot ROM. JTAG is a standard and popular interface; many CPUs, microcontrollers and other devices are manufactured with JTAG interfaces (as of 2009). 888:. Retrieval of the OS from secondary or tertiary store was thus eliminated as one of the characteristic operations for bootstrapping. To allow system customizations, accessories, and other support software to be loaded automatically, the Atari's floppy drive was read for additional components during the boot process. There was a timeout delay that provided time to manually insert a floppy as the system searched for the extra components. This could be avoided by inserting a blank disk. The Atari ST hardware was also designed so the cartridge slot could provide native program execution for gaming purposes as a holdover from Atari's legacy making electronic games; by inserting the 5545: 782:, included an (external) ROM. Gruppi Speciali was, starting from 1975, a fully single-button machine booting into the operating system from a ROM memory composed from semiconductors, not from ferrite cores. Although the ROM device was not natively embedded in the computer of Gruppi Speciali, due to the design of the machine, it also allowed the single-button ROM booting in machines not designed for that (therefore, this "bootstrap device" was architecture-independent), e.g. the PDP-11. Storing the state of the machine after the switch-off was also in place, which was another critical feature in the telephone switching contest. 54: 1062:
instructions typically start an input operation from some peripheral device (which may be switch-selectable by the operator). Other systems may send hardware commands directly to peripheral devices or I/O controllers that cause an extremely simple input operation (such as "read sector zero of the system device into memory starting at location 1000") to be carried out, effectively loading a small number of boot loader instructions into memory; a completion signal from the I/O device may then be used to start execution of the instructions by the CPU.
866:, are so closely interwoven with their hardware that it is impossible to natively boot an operating system other than the standard one. This is the opposite extreme of the scenario using switches mentioned above; it is highly inflexible but relatively error-proof and foolproof as long as all hardware is working normally. A common solution in such situations is to design a boot loader that works as a program belonging to the standard OS that hijacks the system and loads the alternative OS. This technique was used by Apple for its 2000: 1824: 1305: 771:(1971) had a program load switch that, in combination with options that provided two ROM chips, loaded a program into main memory from those ROM chips and jumped to it. Digital Equipment Corporation introduced the integrated-circuit-ROM-based BM873 (1974), M9301 (1977), M9312 (1978), REV11-A and REV11-C, MRV11-C, and MRV11-D ROM memories, all usable as bootstrap ROMs. The PDP-11/34 (1976), PDP-11/60 (1977), PDP-11/24 (1979), and most later models include boot ROM modules. 1471: 1850:(DSPs) may have boot ROM integrated directly into their silicon, so such a processor can perform a simple boot sequence on its own and load boot programs (firmware or software) from boot sources such as NAND flash or eMMC. It is difficult to hardwire all the required logic for handling such devices, so an integrated boot ROM is used instead in such scenarios. Also, a boot ROM may be able to load a boot loader or diagnostic program via serial interfaces like 1487: 311: 717: 261: 1918:, since it usually boots first from its own memories and then controls overall system behavior, including booting of the DSP, and then further controlling the DSP's behavior. The DSP often lacks its own boot memories and relies on the host processor to supply the required code instead. The most notable systems with such a design are cell phones, modems, audio and video players and so on, where a DSP and a CPU/microcontroller are co-existing. 330:(1953), a decimal machine, which had a group of ten 10-position switches on its operator panel which were addressable as a memory word (address 8000) and could be executed as an instruction. Thus setting the switches to 7004000400 and pressing the appropriate button would read the first card in the card reader into memory (op code 70), starting at address 400 and then jump to 400 to begin executing the program on that card. The 513: 323:
the information in these first 80 memory locations to an assembly area where the information in punched cards 2, 3, 4, and so on, could be combined to form the stored program. Once this information was moved to the assembly area, the machine would branch to an instruction in location 080 (read a card) and the next card would be read and its information processed.
295:, or a magnetic drum unit, depending on the position of the Load Selector switch. The left 18-bit half-word was then executed as an instruction, which usually read additional words into memory. The loaded boot program was then executed, which, in turn, loaded a larger program from that medium into memory without further help from the human operator. The 1219:). Some boot loaders can also load other boot loaders; for example, GRUB loads BOOTMGR instead of loading Windows directly. Usually a default choice is preselected with a time delay during which a user can press a key to change the choice; after this delay, the default choice is automatically run so normal booting can occur without interaction. 156:. The usage calls attention to the requirement that, if most software is loaded onto a computer by other software already running on the computer, some mechanism must exist to load the initial software onto the computer. Early computers used a variety of ad-hoc methods to get a small program into memory to solve this problem. The invention of 1283:(PXE) image. No drivers are required, but the system functionality is limited until the operating system kernel and drivers are transferred and started. As a result, once the ROM-based booting has completed it is entirely possible to network boot into an operating system that itself does not have the ability to use the network interface. 696:
tape reader. The difference between the boot loader and second stage loader is the addition of checking code to trap paper tape read errors, a frequent occurrence with relatively low-cost, "part-time-duty" hardware, such as the Teletype Model 33 ASR. (Friden Flexowriters were far more reliable, but also comparatively costly.)
424:, revived it for the design of the System/360, and continues to use it in those environments today. In the System/360 processors, an IPL is initiated by the computer operator by selecting the three hexadecimal digit device address (CUU; C=I/O Channel address, UU=Control unit and Device address) followed by pressing the 4812:), and as soon as the boot sector is a DR-DOS sector, it will find and load them. Of course, it is difficult to put all this into just 512 bytes, the size of a single sector, but this is a major convenience improvement if you have to set up a DR-DOS system, and it is also the key for the DR-DOS multi-OS 835:
introduced in 1976, featured PROM chips that eliminated the need for a front panel for the boot process (as was the case with the Altair 8800) in a commercial computer. According to Apple's ad announcing it "No More Switches, No More Lights ... the firmware in PROMS enables you to enter, display and
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where there is neither a bootstrap ROM nor a hardwired IPL operation. Instead, after the system is reset it reads and executes microinstructions sequentially from a cassette tape drive mounted on the front panel; this sets up a boot loader in RAM which is then executed. However, since this makes few
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file, which is loaded by IBMBIO.COM. The DR-DOS boot sector will find the kernel files as long as they are logically stored in the root directory. Their physical location on the disk, and if they are fragmented or not, is don't care for the DR-DOS boot sector. Hence, you can just copy the kernel
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An erroneous state can trigger bootloops; this state can be caused by misconfiguration from previously known-good operations. Recovery attempts from that erroneous state then enter a reboot, in an attempt to return to a known-good state. In Windows OS operations, for example, the recovery procedure
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As the complexity of today's products increases, single projects, single departments or even single companies can no longer develop total products, causing concurrent and distributed development. Today and worldwide, industries are facing complex product development and its vast array of associated
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EBPB introduced with DOS 7.1 requires even 87 bytes, leaving only 423 bytes for the boot loader when assuming a sector size of 512 bytes. Microsoft boot sectors therefore traditionally imposed certain restrictions on the boot process, for example, the boot file had to be located at a fixed position
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Typically, a microprocessor will, after a reset or power-on condition, perform a start-up process that usually takes the form of "begin execution of the code that is found starting at a specific address" or "look for a multibyte code at a specific address and jump to the indicated location to begin
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The length of the second stage loader is such that the final byte overwrites location 7. After the instruction in location 6 executes, location 7 starts the second stage loader executing. The second stage loader then waits for the much longer tape containing the operating system to be placed in the
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and held a 32 by 16 array of semiconductor diodes. With all 512 diodes in place, the memory contained all "one" bits; the card was programmed by cutting off each diode whose bit was to be "zero". DEC also sold versions of the card, the BM792-Yx series, pre-programmed for many standard input devices
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had a "READ IN" button that, when pressed, reset the processor and started an I/O operation on a device specified by switches on the control panel, reading in a 36-bit word giving a target address and count for subsequent word reads; when the read completed, the processor started executing the code
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VBR would only load the first 29 KB of the file into memory, relying on another loader embedded into the first part of IBMBIO.COM to check for this condition and load the remainder of the file into memory by itself if necessary. This does not cause compatibility problems, as IBMBIO.COM's size
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have a similar mechanism, in which the Load button causes the instruction set up in the entry keys on the front panel is executed, and the channel that instruction sets up is given a command to transfer data to memory starting at address 00100; when that transfer finishes, the CPU jumps to address
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system (c. 1958) used a card reader to load a program from a punched card. The 80 characters stored in the punched card were read into memory locations 001 to 080, then the computer would branch to memory location 001 to read its first stored instruction. This instruction was always the same: move
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Some microcontrollers provide special hardware interfaces which cannot be used to take arbitrary control of a system or directly run code, but instead they allow the insertion of boot code into bootable non-volatile memory (like flash memory) via simple protocols. Then at the manufacturing phase,
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If there is no active partition, or the active partition's boot sector is invalid, the MBR may load a secondary boot loader which will select a partition (often via user input) and load its boot sector, which usually loads the corresponding operating system kernel. In some cases, the MBR may also
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physical sectors and using 386 instructions for size reasons. At the same time other vendors managed to squeeze much more functionality into a single boot sector without relaxing the original constraints on only minimal available memory (32 KB) and processor support (8088/8086). For example,
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Large and complex systems may have boot procedures that proceed in multiple phases until finally the operating system and other programs are loaded and ready to execute. Because operating systems are designed as if they never start or stop, a boot loader might load the operating system, configure
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On systems with those constraints, the first program loaded into RAM may not be sufficiently large to load the operating system and, instead, must load another, larger program. The first program loaded into RAM is called a first-stage boot loader, and the program it loads is called a second-stage
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Smaller computers often use less flexible but more automatic boot loader mechanisms to ensure that the computer starts quickly and with a predetermined software configuration. In many desktop computers, for example, the bootstrapping process begins with the CPU executing software contained in ROM
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Some earlier computer systems, upon receiving a boot signal from a human operator or a peripheral device, may load a very small number of fixed instructions into memory at a specific location, initialize at least one CPU, and then point the CPU to the instructions and start their execution. These
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In case of DSPs there is often a second microprocessor or microcontroller present in the system design, and this is responsible for overall system behavior, interrupt handling, dealing with external events, user interface, etc. while the DSP is dedicated to signal processing tasks only. In such
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such interfaces are used to inject boot code (and possibly other code) into non-volatile memory. After system reset, the microcontroller begins to execute code programmed into its non-volatile memory, just like usual processors are using ROMs for booting. Most notably this technique is used by
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The disk, tape or card deck must contain a special program to load the actual operating system or standalone utility into main storage, and for this specific purpose "IPL Text" is placed on the disk by the stand-alone DASDI (Direct Access Storage Device Initialization) program or an equivalent
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read-type command, but exactly the same procedure is also used to IPL from other input-type devices, such as tape drives, or even card readers, in a device-independent manner, allowing, for example, the installation of an operating system on a brand-new computer from an OS initial distribution
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kernel files must reside on specific locations, but the DR-DOS files can be anywhere, so you don't have to physically swap them around each time you boot the other OS. Also, it allows to upgrade a DR-DOS system simply by copying the kernel files over the old ones, no need for
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The first instruction that is fetched and executed following a hardware reset is located at physical address FFFFFFF0h. This address is 16 bytes below the processor's uppermost physical address. The EPROM containing the software-initialization code must be located at this
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command and slightly relaxed in later versions of DOS. The boot loader was then able to load the first three sectors of the file into memory, which happened to contain another embedded boot loader able to load the remainder of the file into memory. When Microsoft added
1027:(especially on x86 systems), to access the nonvolatile device (usually block-addressed device, e.g. NAND flash, SSD) or devices from which the operating system programs and data can be loaded into RAM; in addition, this program may initialize display devices (such as 1862:
and so on. This feature is often used for system recovery purposes, or it could also be used for initial non-volatile memory programming when there is no software available in the non-volatile memory yet. Many modern microcontrollers (e.g. flash memory controller on
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initialization using CPU cache as RAM) and load the larger, fully featured version of U-Boot. Some CPUs and SoCs may not use CPU cache as RAM on boot process, they use an integrated boot processor to do some hardware configuration, to reduce cost.
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are designed to execute this software after reset without outside help). This software contains rudimentary functionality to search for devices eligible to participate in booting, and load a small program from a special section (most commonly the
4570:; Rubin, Darryl; Ryan, Ralph; Schulmeisters, Karl; Shah, Rajen; Shaw, Barry; Short, Anthony; Slivka, Ben; Smirl, Jon; Stillmaker, Betty; Stoddard, John; Tillman, Dennis; Whitten, Greg; Yount, Natalie; Zeck, Steve (1988). "Technical advisors". 197:, had no program stored in memory, but was set up for each problem by a configuration of interconnecting cables. Bootstrapping did not apply to ENIAC, whose hardware configuration was ready for solving problems as soon as power was applied. 4715:
so you don't have to worry about leaving the first cluster free on a disk that you want to make bootable. The DR DOS system files can be located anywhere on the disk, so any disk with enough free space can be set to boot your system.
1953:, which might or might not be approved by the manufacturer. Modern boot loaders make use of concurrency, meaning they can run multiple processor cores, and threads at the same time, which add extra layers of complexity to secure booting. 547:, which did not lose its information when power was off, these bootstrap loaders would remain in place unless they were erased. Erasure sometimes happened accidentally when a program bug caused a loop that overwrote all of memory. 160:(ROM) of various types solved this paradox by allowing computers to be shipped with a start up program that could not be erased. Growth in the capacity of ROM has allowed ever more elaborate start up procedures to be implemented. 4030: 1201:
Many boot loaders (like GNU GRUB, rEFInd, Windows's BOOTMGR, Syslinux, and Windows NT/2000/XP's NTLDR) can be configured to give the user multiple booting choices. These choices can include different operating systems (for
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manual incorrectly states that the system files no longer need to be contiguous. However, for the boot process to work the system files still need to occupy the first two directory entries and the first three sectors of
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Since the CS register contains F000 (thus specifying a code segment starting at physical address F0000) and the instruction pointer contains FFF0, the processor will execute its first instruction at physical address
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UU was often of the form Uu, U=Control unit address, u=Device address, but some control units attached only 8 devices; some attached more than 16. Indeed, the 3830 DASD controller offered 32-drive-addressing as an
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representation. Since this has been mixed up numerous times in books and even in original Microsoft reference documents, this article uses the offset-based byte-wise on-disk representation to avoid any possible
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microcontrollers, and by others as well. In many cases such interfaces are implemented by hardwired logic. In other cases such interfaces could be created by software running in integrated on-chip boot ROM from
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from different partitions or drives), different versions of the same operating system (in case a new version has unexpected problems), different operating system loading options (e.g., booting into a rescue or
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After RESET, address lines A31–20 are automatically asserted for instruction fetches. This fact, together with the initial values of CS:IP, causes instruction execution to begin at physical address FFFFFFF0H.
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As the I/O operations needed to cause a read operation on a minicomputer I/O device were typically different for different device controllers, different bootstrap programs were needed for different devices.
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470V/6 and related CPUs supported four hexadecimal digits on those CPUs which had the optional second channel unit installed, for a total of 32 channels. Later, IBM would also support more than 16 channels.
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included features to make their operation simpler. They typically included instructions that performed a complete input or output operation. The same hardware logic could be used to load the contents of a
535:(1965) simplified design by using the CPU to assist input and output operations. This saved cost but made booting more complicated than pressing a single button. Minicomputers typically had some way to 444:-like device. For example, on the System/370 Model 158, the keyboard sequence 0-7-X (zero, seven and X, in that order) results in an IPL from the device address which was keyed into the input area. The 4873:
does not only partition a disk, but can also format the freshly created volumes and initialize their boot sectors in one go, so there's no risk to accidentally mess up the wrong volume and no need for
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may be split into two stages: the platform would load a small SPL (Secondary Program Loader), which is a stripped-down version of U-Boot, and the SPL would do some initial hardware configuration (e.g.
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execution". A system built using that microprocessor will have the permanent ROM occupying these special locations so that the system always begins operating without operator assistance. For example,
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Early computers in the 1940s and 1950s were one-of-a-kind engineering efforts that could take weeks to program and program loading was one of many problems that had to be solved. An early computer,
4546:; Borman, Reuben; Borman, Rob; Butler, John; Carroll, Chuck; Chamberlain, Mark; Chell, David; Colee, Mike; Courtney, Mike; Dryfoos, Mike; Duncan, Rachel; Eckhardt, Kurt; Evans, Eric; Farmer, Rick; 456:, and its compatibles such as Amdahl's, reads 24 bytes from an operator-specified device into main storage starting at real address zero. The second and third groups of eight bytes are treated as 180:
There are many different methods available to load a short initial program into a computer. These methods reach from simple, physical input to removable media that can hold more complex programs.
4135: 1415:(POST). In this example of dual booting, the user chooses by inserting or removing the DVD from the computer, but it is more common to choose which operating system to boot by selecting from a 464:, with command chaining and suppress incorrect length indication being enforced). When the I/O channel commands are complete, the first group of eight bytes is then loaded into the processor's 1190:, are not themselves operating systems, but are able to load an operating system properly and transfer execution to it; the operating system subsequently initializes itself and may load extra 504:
IBM introduced some evolutionary changes in the IPL process, changing some details for System/370 Extended Architecture (S/370-XA) and later, and adding a new type of IPL for z/Architecture.
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In a minicomputer with a paper tape reader, the first program to run in the boot process, the boot loader, would read into core memory either the second-stage boot loader (often called a
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The boot process can be considered complete when the computer is ready to interact with the user, or the operating system is capable of running system programs or application programs.
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used front panel switches to cause the computer to automatically load instructions into memory from a device specified by the front panel's data switches, and then jump to loaded code.
4021: 1194:. The second-stage boot loader does not need drivers for its own operation, but may instead use generic storage access methods provided by system firmware such as the BIOS, UEFI or 4829:. You can even have multiple DR-DOS kernel files under different file names stored on the same drive, and LOADER will switch between them according to the file names listed in the 4665: 4719:(NB. The source attributes this to the SYS utility while in fact this is a feature of the advanced bootstrap loader in the boot sector. SYS just plants this sector onto the disk.) 100:, which can be "hard", e.g. after electrical power to the CPU is switched from off to on, or "soft", where the power is not cut. On some systems, a soft boot may optionally clear 3290: 360:) 0 and initiated the load sequence by causing PP 0 to execute the code loaded into memory. PP 0 loaded the necessary code into its own memory and then initialized the other PPs. 3927: 1250:
itself as a mere process within that system, and then irrevocably transfer control to the operating system. The boot loader then terminates normally as any other process would.
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booted its disk operating systems using a series of very small incremental steps, each passing control onward to the next phase of the gradually more complex boot process. (See
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As with the second-stage boot loader, network booting begins by using generic network access methods provided by the network interface's boot ROM, which typically contains a
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so the device can begin functioning immediately; little or no loading is necessary, because the loading can be precomputed and stored on the ROM when the device is made.
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In addition to loading an operating system or stand-alone utility, the boot process can also load a storage dump program for diagnosing problems in an operating system.
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when the machine was powered up, and then to read software from a boot device and execute it. Firmware compatible with the BIOS on the IBM Personal Computer is used in
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do not require a noticeable boot sequence to begin functioning and when turned on may simply run operational programs that are stored in ROM. All computing systems are
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processor, initialization begins by reading a two-byte vector address at $ FFFD (MS byte) and $ FFFC (LS byte) and jumping to that location to run the bootstrap code.
805:-based console processor, and the VAX-11/730 had an 8085-based console processor. These console processors could boot the main processor from various storage devices. 468:(PSW) and the startup program begins execution at the location designated by that PSW. The IPL device is usually a disk drive, hence the special significance of the 3539: 1770:(followed by an INT 19h just in case INT 18h would return) in order to give back control to the BIOS, which would then attempt to boot off other devices, attempt a 892:
cartridge with the Macintosh system ROM in the game slot and turning the Atari on, it could "natively boot" the Macintosh operating system rather than Atari's own
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and some later systems, the functions of the switches and the LOAD button are simulated using selectable areas on the screen of a graphics console, often an
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program running under an operating system, e.g., ICKDSF, but IPL-able tapes and card decks are usually distributed with this "IPL Text" already present.
497:; seeks and searches are not simulated by tape and card controllers, as for these device classes a Read IPL command is simply a sequential read command. 104:
to zero. Both hard and soft booting can be initiated by hardware such as a button press or by a software command. Booting is complete when the operative
5057: 3156: 847:). Because so little of the disk operating system relied on ROM, the hardware was also extremely flexible and supported a wide range of customized disk 3333: 2584:
never exceeded this limit in previous versions without this loader. Combined with a dual entry structure this also allows the system to be loaded by a
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assumptions about the system it can equally well be used to load diagnostic (Maintenance Test Routine) tapes which display an intelligible code on the
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file into memory: If the IBMBIO.COM file is larger than some 29 KB, trying to load the whole file into memory would result in the boot loader to
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for the PDP-11 that stored a bootstrap program of up to 32 words (64 bytes). It consisted of a printed circuit card, the M792, that plugged into the
168: 4246: 1525:) entry point inside the ROM. This memory location typically contains a jump instruction that transfers execution to the location of the firmware ( 1150:(PBR) was coded to require at least 32 KB (later expanded to 64 KB) of system memory and only use instructions supported by the original 661:
A related example is based on a loader for a Nicolet Instrument Corporation minicomputer of the 1970s, using the paper tape reader-punch unit on a
367:(c. 1965) had a "SYSTEM BOOTLOAD" button that, when pressed, caused one of the I/O controllers to load a 64-word program into memory from a diode 307:
had similar mechanisms, but with different load buttons for different devices. The term "boot" has been used in this sense since at least 1958.
5203: 5473: 3752: 2677: 1054:. Often, multiple-stage boot loaders are used, during which several programs of increasing complexity load one after the other in a process of 3477: 2990: 5257: 3505: 4881:. Afterwards, you could just copy over the remaining DR-DOS files, including the system files. It is important to know that, in contrast to 4119: 808:
Some other superminicomputers, such as the VAX-11/750, implement console functions, including the first stage of booting, in CPU microcode.
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Boot loaders may face peculiar constraints, especially in size; for instance, on the IBM PC and compatibles, the boot code must fit in the
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identification, authorization, and authentication are separable concerns in an SSO session. When recovery of a site is indicated (viz. a
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DR-DOS boot sectors are able to locate the boot file in the FAT12, FAT16 and FAT32 file system, and load it into memory as a whole via
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When a computer is turned off, its software‍—‌including operating systems, application code, and data‍—‌remains stored on
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The VBR is often OS-specific; however, its main function is to load and execute the operating system boot loader file (such as
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A bootable MBR device is defined as one that can be read from, and where the last two bytes of the first sector contain the
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successors to the PDP-4 have an added Read-In button to read a program in from paper tape and jump to it. The Data General
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attempt to load secondary boot loaders before trying to boot the active partition. If all else fails, it should issue an
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panel with 144 toggle switches; the dead start switch entered 12 12-bit words from the toggle switches to the memory of
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Intel 64 and IA-32 Architectures Software Developer's Manual Volume 3 (3A, 3B, 3C & 3D): System Programming Guide
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IBM System/3 console from the 1970s. Program load selector switch is lower left; Program load switch is lower right.
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to transfer a fixed program into memory when its start button was pressed. The program stored on this device, which
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Chappell, Geoff (January 1994). "Chapter 2: The System Footprint". In Schulman, Andrew; Pedersen, Amorette (eds.).
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is displayed on an airport terminal screen) personal site visits might be required to remediate the situation.
1366:, USB hard disk drive, USB optical disc drive, USB solid-state drive, etc.), or a network interface card (using 2521: 1273: 4930: 4616: 3143: 6180: 5785: 5515: 5459: 5406: 5132: 3953: 3923: 3893: 3863: 3791: 3761: 3731: 3694: 3656: 3625: 3595: 3565: 3535: 3419: 3389: 3359: 3329: 3320: 3299: 3189: 2168: 1707: 1367: 1280: 1211:), and some standalone programs that can function without an operating system, such as memory testers (e.g., 740: 524: 131:, and a reboot may be the only method to return to a designated zero-state from an unintended, locked state. 5544: 3180: 2833: 1723:
in the root directory of the file system and stored as consecutive sectors, conditions taken care of by the
89:, so some process must load software into memory before it can be executed. This may be done by hardware or 5639: 3220: 946: 928: 280: 4264: 2609: 2050:
before a boot sequence is finished, a restart might prevent a user from accessing the regular interface.
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Most DSPs have a serial mode boot, and a parallel mode boot, such as the host port interface (HPI boot).
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installed on the hard drive, the user could set the boot order to the one given above, and then insert a
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into what is usually a variant of Linux for various simple tasks such as Internet access; examples are
990: 351: 17: 5848: 5674: 5646: 2181: 2098: 1847: 1688: 1585: 4180: 2977: 2669: 5524: 3473: 3122: 2493: 2369: 2352: 2348: 1754:), which is the second-stage boot loader, from an active partition. Then the boot loader loads the 1731: 1603:) and transfers execution to the boot code. In the case of a hard disk, this is referred to as the 1003:. When the computer is powered on, it typically does not have an operating system or its loader in 5087:(conference 19-21 September 2003) Workshop: defect detection in distributed software development 1941:
of the booting process. Some of them are made mandatory, others can be disabled or enabled by the
1652:), or where it is otherwise established that the code inside the sector is executable on x86 PCs. 768: 764: 4846: 4496: 4402: 3854: 3840: 3057: 3007: 2947: 2525: 2344: 2263: 1581: 1411:, in which the user chooses which operating system to start after the computer has performed its 1216: 966: 120: 82: 5013: 3350: 5131:
Eye Security update: the Breaking Change, 4:09 AM UTC on July 19th 2024, reverted 05:27 AM UTC
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The boot device is the storage device from which the operating system is loaded. A modern PC's
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include a separate console processor that bootstraps the main processor. The PDP-11/44 had an
609: 5382: 4686: 4574:. By Duncan, Ray; Bostwick, Steve; Burgoyne, Keith; Byers, Robert A.; Hogan, Thom; Kyle, Jim; 2895: 592:
has a hardware loader, such that an operator need only push the "load" switch to instruct the
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computers of the 1950s and early 1960s, but IBM used the term "Initial Program Load" with the
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techniques to squeeze everything into a single physical sector, as it was a requirement for
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It is also possible to take control of a system by using a hardware debug interface such as
1272:, and certain parts of it are transferred to the client using a simple protocol such as the 1242:
to start is generally unacceptable. Therefore, such devices have software systems in ROM or
6055: 6021: 5971: 5841: 5736: 5653: 5577: 5570: 4980: 4874: 2102: 2065: 1950: 1810: 1740: 1352: 1336: 1114:, sometimes called the zero-stage boot loader, can find and load first-stage boot loaders. 1004: 544: 457: 3380: 949:
interpreter, with much of the firmware being written in Forth. It was standardized by the
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processors always start by running the instructions beginning at F000:FFF0, while for the
53: 8: 6062: 6035: 5866: 5706: 5660: 4870: 2643: 2509: 1828: 1767: 1607:(MBR). The conventional MBR code checks the MBR's partition table for a partition set as 1565: 1407:
without having to install an operating system onto the hard drive. This is an example of
1000: 465: 288: 5121:(20 Jul 2024) CrowdStrike IT outage affected 8.5 million Windows devices, Microsoft says 4182: 3253: 1910:
systems the DSP could be booted by another processor which is sometimes referred as the
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Compaq Computer Corporation; Phoenix Technologies Ltd; Intel Corporation (1996-01-11).
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or LBA, even if the file is not stored in a fixed location and in consecutive sectors.
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An Italian telephone switching computer, called "Gruppi Speciali", patented in 1975 by
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Eleventh Annual International Workshop on Software Technology and Engineering Practice
3837:
Alberto Ciaramella discusses the patent for bootstrapping computers conceived at CSELT
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that occurs on computing devices; when those devices repeatedly fail to complete the
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Once the BIOS has found a bootable device it loads the boot sector to linear address
1393: 1328: 1032: 970: 912: 786: 662: 555: 74: 5334:"Google Nest Hub gets a new UI that's so fresh it could bootloop your smart display" 3832:
Alberto Ciaramella racconta il brevetto del boostrap dei computer concepito in CSELT
2288:
CrowdStrike reverted the content update at 05:27 UTC, This left machines stuck in a
37:
This article is about bootstrapping operating systems. For the general concept, see
30:"Quick boot" redirects here. For the feature of the Quarterdeck memory manager, see 6352: 6295: 6242: 6235: 5821: 5743: 5208: 5062: 4762:) file and then loads the *whole* file into memory before it passes control to it. 3152: 2768: 2517: 2365: 2156: 1634: 1616: 1265: 1020: 1008: 938: 934: 885: 732: 577: 421: 368: 250: 157: 124: 109: 31: 669:. The bytes of its second-stage loader are read from paper tape in reverse order. 6171: 5729: 5584: 5120: 4583: 4579: 4563: 4365: 2829: 2798: 2727: 2529: 2248: 2148: 1999: 1956: 1914:(giving name to a Host Port). Such a processor is also sometimes referred as the 1871: 1864: 1771: 1672: 1660: 1385:
Typically, the system firmware (UEFI or BIOS) will allow the user to configure a
1359: 1332: 1259: 1231: 1198:, though typically with restricted hardware functionality and lower performance. 848: 844: 284: 205: 5189: 3896:. February 1979. 2.3 BOOTSTRAPPING and 3.6.1 Boot Command (B). EK-11780-UG-001. 2334:
Excluding the 370/145 and 370/155, which used a 3210 or 3215 console typewriter.
5699: 5235: 5109:(23 Jul 2024) Inside the 78 minutes that took down millions of Windows machines 5086: 4535: 4315:"How to Enter the BIOS on Any PC: Access Keys by Manufacturer | Tom's Hardware" 2804: 2786: 2124: 2114: 2094: 1490: 1235: 1099: 1036: 969:
specification defined another firmware standard, which was implemented on some
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as IEEE standard 1275-1994; firmware that implements that standard was used in
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Other minicomputers with such simple form of booting include Hewlett-Packard's
408: 404: 254: 105: 4398: 4285: 3830: 3816: 3499: 2068:, before recovery is indicated. Detection of an erroneous state may require a 1959:
argued that booting security serves a legitimate goal but in doing so chooses
1823: 1627:(VBR), and executes it. The MBR boot code is often operating-system specific. 6346: 5894: 5887: 5625: 5554: 5309:"Google thinks it has solved the mystery of the cursed bootlooping wallpaper" 5173: 4901: 4575: 4555: 4551: 4543: 2698: 2638: 2406: 2293: 2208: 2189: 2081:
was to reboot three times, the reboots needed to return to a usable menu.
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The system might exhibit its erroneous state, say in an explicit bootloop or
1981:
Measured boot with the Trusted Platform Module, also known as "trusted boot".
1631: 1553:, further complicated by the fact that at this point memory is very limited. 1419:
menu on the selected device, by using the computer keyboard to select from a
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Examples of first-stage (hardware initialization stage) boot loaders include
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computer (1952–1956) had a "Load" button that initiated reading of the first
242: 238: 141: 128: 119:(suspension) does not involve booting; however, restoring it from a state of 38: 5431:"Botched security update breaks Windows worldwide, causing BSOD and crashes" 5144: 4609: 3817:
Device for automatically loading the central memory of electronic processors
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processors (note the swapped order), whereas it would have to be written as
632:
for the boot loader might be as simple as the following eight instructions:
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VBR, which would load only the first three sectors of the file into memory.
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via CSM) does not rely on boot sectors, UEFI system loads the boot loader (
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PDP-8/E front panel showing the switches used to load the bootstrap program
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file into memory before it executes it. It does not care at all about the
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designs may also include an intermediary boot sequence step. For example,
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Unix implementation and copied by various freeware operating systems and
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on 32-bit and 64-bit x86 processors), usually pointing to the firmware (
1007:(RAM). The computer first executes a relatively small program stored in 6316: 6302: 6142: 5814: 5616: 5451: 5093: 5058:"Microsoft blocks UEFI bootloaders enabling Windows Secure Boot bypass" 4804: 4800: 4759: 4755: 4712: 4648:. The Andrew Schulman Programming Series (1st printing, 1st ed.). 4547: 4539: 2569: 2561: 2541: 2537: 2445: 2440: 2426: 2243: 2140: 2129: 1875: 1692: 1656: 1546: 1436: 1139: 1075: 994: 863: 794: 790: 716: 629: 593: 433: 429: 318:
Other IBM computers of that era had similar features. For example, the
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The boot sector code is the first-stage boot loader. It is located on
923:-based machines, and later also used as an alternative to the BIOS in 260: 6288: 5936: 5771: 5764: 5720: 5262: 4847:"The continuing saga of Windows 3.1 in enhanced mode on OmniBook 300" 3764:. February 1979. pp. 1–10, 2-29–2-34, 3-1–3-6. EK-11060-OP-003. 2418: 2213: 2144: 2019: 1895: 1783: 1755: 1734:
and FAT32 support, they even switched to a boot loader reaching over
1502: 1375: 1208: 1203: 1135: 1016: 974: 958: 893: 859: 818: 62: 5284:"'It was unintentional,' says creator of 'cursed' Android wallpaper" 5145:
Ruley, John D.; David Methvin; Tom Henderson; Martin Heller (1997).
1268:. In this scenario, the operating system is stored on the disk of a 6309: 6274: 6108: 5964: 5901: 5757: 5750: 5482: 5231:"Windows 10 update sending PCs into endless boot cycle: What to do" 4926: 4830: 4373: 3558:
M9301 bootstrap/terminator module maintenance and operator's manual
2289: 2135: 1942: 1806: 1475: 1427:
Boot Menu, or both; the Boot Menu is typically entered by pressing
1312: 1179: 1167: 1166:
Second-stage (OS initialization stage) boot loaders, such as shim,
1131: 1111: 942: 878: 840: 822: 752: 736: 625: 441: 437: 343: 331: 319: 304: 300: 265: 225: 90: 78: 70: 3956:. December 1982. pp. 1-2–1-4, B-1–B-8, C-1–C-2. AA-K410C-TE. 1327:
firmware supports booting from various devices, typically a local
512: 224:
The first programmable computers for commercial sale, such as the
6203: 5943: 5922: 5873: 5713: 5692: 4214: 2253: 2218: 2011: 2007: 1479: 1400: 1175: 954: 920: 832: 551: 327: 296: 273: 229: 4601: 3438: 3436: 884:, were "instant-on", with the operating system executing from a 371:
and deliver an interrupt to cause that program to start running.
6256: 5985: 5950: 5204:"New Windows Server updates cause DC boot loops, break Hyper-V" 4886: 4882: 4867: 4826: 4817: 4813: 4796: 4751: 4528: 4506:. May 2012. Section 9.1.4 First Instruction Executed, p. 2611. 4260: 2585: 2554: 2513: 2501: 2477: 2473: 2410: 2047: 1926: 1696: 1545:), the PCI bus and the PCI devices (including running embedded 1379: 1171: 1071: 1012: 802: 605: 581: 563: 452:
The IPL function in the System/360 and its successors prior to
375: 277: 253:
and later used it for their mainframe lines, starting with the
93:
in the CPU, or by a separate processor in the computer system.
5383:"CrowdStrike Update Pushing Windows Machines Into a BSOD Loop" 4951: 4639: 4637: 4635: 4497:"Intel 64 and IA-32 Architectures Software Developer's Manual" 2800:
The Preparation of Programs for an Electronic Digital Computer
1695:
loaders have to be supported as well in some environments. In
1568:("boot device sequence") until it finds one that is bootable. 1083:) of the most promising device, typically starting at a fixed 6249: 6101: 5957: 5929: 5908: 4558:; Olsson, Mike; Osterman, Larry; Ostling, Ridge; Pai, Sunil; 4430: 3433: 3059:
650 magnetic drum data-processing machine manual of operation
2497: 1719: 1715: 1711: 1664: 1404: 1397: 1187: 1183: 962: 779: 744: 721: 601: 597: 589: 559: 532: 528: 453: 387: 204:
system, the second stored-program computer to be built, used
201: 194: 173: 4695:. Vol. 10, no. 3. p. 241–246, 257, 264, 266. 2480:
counterparts could still be achieved utilizing conventional
2355:
used a keyboard/display device compatible with nothing else.
1867:) have firmware ROM integrated directly into their silicon. 1813:) directly, and the OS kernel is loaded by the boot loader. 1098:(PBR), which in turn are limited to a single sector; on the 961:
and some other PowerPC-based machines, as well as Sun's own
477:
command also causes the selected device to seek to cylinder
6194: 6187: 6156: 5978: 5632: 5609: 5602: 4632: 4534: 4468:. Intel. 1986. Section 10.2.3 First Instructions, p. 10-3. 2152: 2003: 1922: 1900: 1887: 1879: 1851: 1843: 1791: 1561: 1542: 1530: 1522: 1424: 1420: 1324: 1320: 1234:
must boot immediately. For example, waiting a minute for a
1155: 1151: 1127: 1123: 1067: 1024: 950: 916: 904: 871: 867: 539:
short programs by manipulating an array of switches on the
338:
IBM's competitors also offered single button program load.
5174:"Disabling automatic reboot prevents possible reboot loop" 3820:
U.S. Patent No. 4,117,974. 1978-10-03. (submitted in 1975)
2949:
704 Electronic Data-Processing Machine Manual of Operation
2536:- and cross-compatibility with other operating systems in 2464:
As an example, while the extended functionality of DR-DOS
2433: 2147:
value exceeded the maximum of 255 which happened due to a
1839:
Many modern CPUs, SoCs and microcontrollers (for example,
1549:). One of the most involved steps is setting up DRAM over 1074:) at a predefined address (some CPUs, including the Intel 1042:
The small program that starts this sequence is known as a
751:, reduced the physical size and cost of ROM. This allowed 711: 615: 5258:"Google has tried everything but building the best phone" 3262: 3092: 3016: 2986: 2956: 2897:
Principles of Operation Type 701 And Associated Equipment
2159:. This then crashed the SystemUI component on every boot. 1937:
Various measures have been implemented which enhance the
1859: 1498: 1286: 1028: 924: 907:; one of the functions of that firmware was to perform a 798: 246: 212:
completed in late 1948, loaded further instructions from
101: 3916:
VAX-11/730 Central Processing Unit Technical Description
2413:
compatible machines, this can be written as 16-bit word
2296:. and devices booted after the revert were not affected. 1537:(POST) to check and initialize required devices such as 1225: 839:
Due to the expense of read-only memory at the time, the
628:
or the operating system from an outside storage medium.
596:
reader to load a program directly into core memory. The
237:(the most typical ones) or other input media, such as a 5350: 5034:"mjg59 | Boot Guard and PSB have user-hostile defaults" 4825:, no difficult setup procedures as required for MS-DOS/ 4239:"Chapter 6 - Troubleshooting Startup and Disk Problems" 1925:
chips load their configuration from an external serial
755:
boot programs to be included as part of the computer.
5358:"Statement on Falcon Content Update for Windows Hosts" 5081: 5079: 3734:. July 1977. pp. 1–5, 2-1–2-12. EK-11034-UG-001. 3684:"11 MRVll·D Universal Programmable Read.Only Memory". 2284: 2282: 2280: 2070:
distributed event store and stream-processing platform
1450:
Several devices are available that enable the user to
1215:), a basic shell (as in GNU GRUB), or even games (see 183: 5133:(19 Jul 2024) BSOD error in latest CrowdStrike update 4399:"Voodoo Envy's Instant-On IOS (powered by Splashtop)" 4286:"List of PC brands with their corresponding hot-keys" 1497:
Upon starting, an IBM-compatible personal computer's
1110:
boot loader. On many embedded CPUs, the CPU built-in
945:, later known as Open Firmware, which incorporated a 811: 3866:. February 1979. p. 6-57. EK-KD11Z-TM-001. 2979:
Operator's Guide for IBM 7090 Data Processing System
2039: 1945:. Traditionally, booting did not involve the use of 1556:
After initializing required hardware, the firmware (
1370:). Older, less common BIOS-bootable devices include 115:
The process of returning a computer from a state of
5076: 4433:. 1983. Section 5.3 SYSTEM INITIALIZATION, p. 5-7. 4345:"MontaVista Linux drives Dell's quick-boot feature" 4212: 3292:
BM792 read-only-memory and MR11~DB bootstrap loader
2547: 2277: 2075: 1023:, to initialize CPU and motherboard, to initialize 937:originally had vendor-specific ROM-based firmware. 699: 4113: 4111: 4109: 4107: 4105: 3588:M9312 bootstrap/terminator module technical manual 3115:CONTROL DATA 6600 Computer System Reference Manual 2877:. IBM. August 1961. pp. 125–127. A22-6530-2. 2143:: when setting a specific image as wallpaper, the 2059: 1264:Most computers are also capable of booting over a 5399: 5148:Networking Windows NT 4.0: Workstation and Server 5125: 4572:The MS-DOS Encyclopedia: versions 1.0 through 3.2 2785: 2409:representation must be assumed in the context of 2072:for real-time operation of a distributed system. 682:Read a byte from paper tape reader to accumulator 645:Read a byte from paper tape reader to accumulator 6344: 2834:"The System Design of the IBM Type 701 Computer" 2460: 2458: 2425:in programs for other CPU architectures using a 1816: 836:debug programs (all in hex) from the keyboard." 398: 4102: 3794:. June 1981. p. 1-6. EK-11024-TM-001. 1671:in order to leave room for the default 64-byte 1102:, the size is limited by the IPL medium, e.g., 485:, simulating a Seek cylinder and head command, 383:A noteworthy variation of this is found on the 81:command. After it is switched on, a computer's 5858: 5407:"CrowdStrike Falcon blue screen issue updates" 5228: 5103: 5101: 4678: 3926:. May 1982. p. 1-9. EK-KA730-TD-001. 2863: 2861: 2755: 858:Some operating systems, most notably pre-1995 5467: 5113: 4902:"Intel Platform Innovation Framework for EFI" 4139: 2614:Computer Dictionary of Information Technology 2455: 2452:continues to take care of these requirements. 2375: 2372:, e.g., OS/2 Boot Manager, rather than an OS. 1675:with four partition entries and the two-byte 219: 5014:"The boot process rxos 1.0rc1 documentation" 2871:Reference Manual 7030 Data Processing System 1835:device, showing additional available options 1161: 379:read in by jumping to the last word read in. 5098: 4687:"DR DOS 5.0 - The better operating system?" 4052:Osborne 4&8-Bit Microprocessor Handbook 4046: 3973: 3754:PDP-11/60 installation and operation manual 2858: 1117: 6069: 5474: 5460: 4176: 4174: 4172: 3501:Altair 8800 loads 4K BASIC from paper tape 3352:Programmed Data Processor-7 Users Handbook 3085:Operator's Guide for IBM 7040-7044 Systems 801:line of 32-bit superminicomputers, had an 685:Store accumulator to address in P register 648:Store accumulator to address in P register 588:Following the older approach, the earlier 407:and its successors, including the current 264:Initial program load punched card for the 5255: 5085:J.J.M. Trienekens; R.J. Kusters. (2004) 4838: 4767: 4722: 3222:Burroughs B 1700 Systems Reference Manual 2520:, controlled utilization of (documented) 1035:) and pointer input devices (such as the 735:(ROM), with its many variants, including 704:The earliest microcomputers, such as the 585:by simply omitting the unneeded diodes. 473:magnetic tape. For disk controllers, the 77:such as a button on the computer or by a 5481: 4643: 4424:"iAPX 286 Programmer's Reference Manual" 4370:"SplashTop Linux On HP, Dell Notebooks?" 4145: 3248: 3246: 2828: 2553:There is one exception to the rule that 2188:systems worldwide stuck in bootloops or 1998: 1822: 1564:) goes through a pre-configured list of 1533:) start-up program. This program runs a 1485: 1469: 1303: 1142:. On the IBM PC, the boot loader in the 715: 511: 493:, simulating a Search ID Equal command, 309: 259: 167: 52: 5331: 4981:"Overview – The four bootloader stages" 4364: 4169: 4148:"Why BIOS loads MBR into 7C00h in x86?" 4054:. Osborne/McGraw-Hill. pp. 10–20. 3265:. September 2005. pp. Chapter 17. 2761:IEEE Annals of the History of Computing 919:was developed by Intel, originally for 903:included ROM-based firmware called the 731:The introduction of integrated circuit 712:Integrated circuit read-only memory era 616:Early minicomputer boot loader examples 411:machines, the boot process is known as 14: 6345: 5171: 4808:files to the disk (even with a simply 3986:. OSBORNE/McGraw-Hill. pp. 5–27. 3980:Osborne 16-Bit Microprocessor Handbook 3946:VAX-11/750 Software Installation Guide 3646:"10 MRV11-C Read-Only Memory Module". 3255:z/Architecture Principles of Operation 3215: 3213: 3182:PDP-10 System Reference Manual, Part 1 2448:still need to be stored contiguously. 1706:, up to 59 bytes are occupied for the 1287:IBM-compatible personal computers (PC) 984: 573:DEC later added, in 1971, an optional 153:to pull oneself up by one's bootstraps 5455: 5380: 5306: 4684: 4463:"80386 Programmer's Reference Manual" 4342: 4087:"An Introduction to RISC-V Boot flow" 4075:Apple Ad, Interface Age, October 1976 3243: 2728:"Pull yourself up by your bootstraps" 1226:Embedded and multi-stage boot loaders 543:. Since the early minicomputers used 96:Restarting a computer also is called 4851:MoHPC - the Museum of HP Calculators 4844: 4773: 4728: 4117: 2930:, Jeremy M. Norman, 2005, page 436, 2097:(SSO) for some applications; in the 395:even in cases of gross CPU failure. 172:Switches and cables used to program 112:and some applications, is attained. 57:A flow diagram of a computer booting 3232:. November 1973. p. 1-14. 3210: 2565: 1929:("configuration ROM") on power-up. 1718:volumes since DOS 4.0, whereas the 1623:code from that partition, known as 1300:System partition and boot partition 1031:), text input devices (such as the 184:Pre integrated-circuit-ROM examples 24: 3497: 3392:. January 1968. p. 10-3. 3302:. January 1974. DEC-II-HBMAA-E-D. 2343:Only the S/360 used the 2250; the 2091:Security Assertion Markup Language 2084: 2038:) is a diagnostic condition of an 1949:. The security can be bypassed by 1663:, and must fit into the first 446 1595:, but some BIOSes erroneously use 1343:(MBR) on such a drive or disk, an 1253: 812:Microprocessors and microcomputers 758: 624:) that could read paper tape with 188: 25: 6364: 5172:Shultz, Gregory (February 2001). 4845:Paul, Matthias R. (2017-08-14) . 4650:Addison Wesley Publishing Company 4146:Sakamoto, Masahiko (2010-05-13). 4118:Paul, Matthias R. (1997-10-02) . 3856:PDP-11/44 System Technical Manual 3784:PDP-11/24 System Technical Manual 3618:Microcomputer Interfaces Handbook 3422:. August 1969. p. 10-3. 3065:. IBM. 1955. pp. 49, 53–54. 2759:(1980). "Programming the EDSAC". 2093:(SAML), which can also implement 1619:is found, the MBR code loads the 1439:is typically entered by pressing 1087:such as the start of the sector. 929:Apple Macs using Intel processors 554:series (mid-1960s), the original 5543: 5423: 5374: 4774:Paul, Matthias R. (2002-02-20). 4729:Paul, Matthias R. (2001-01-17). 4664:(xxvi+738+iv pages, 3.5"-floppy 4627:from the original on 2018-10-14. 4617:"The MS-DOS Encyclopedia (1988)" 4036:from the original on 2022-10-09. 3963:from the original on 2022-10-09. 3933:from the original on 2022-10-09. 3903:from the original on 2022-10-09. 3886:VAX-11/780 Hardware User's Guide 3873:from the original on 2022-10-09. 3843:from the original on 2021-11-13. 3801:from the original on 2022-10-09. 3771:from the original on 2022-10-09. 3741:from the original on 2022-10-09. 3635:from the original on 2022-10-09. 3605:from the original on 2022-10-09. 3575:from the original on 2022-10-09. 3545:from the original on 2022-10-09. 3538:. April 1974. DEC-11-H873A-B-D. 3462:from the original on 2022-10-09. 3455:. April 1971. p. 2-30. 3429:from the original on 2022-10-09. 3399:from the original on 2022-10-09. 3369:from the original on 2022-10-09. 3339:from the original on 2022-10-09. 3309:from the original on 2022-10-09. 3239:from the original on 2022-10-09. 3132:from the original on 2022-10-09. 3102:from the original on 2022-10-09. 3072:from the original on 2022-10-09. 3026:from the original on 2022-10-09. 3009:IBM 7094 Principles of Operation 2996:from the original on 2022-10-09. 2966:from the original on 2022-10-09. 2884:from the original on 2022-10-09. 2854:from the original on 2022-10-09. 2089:Recovery might be specified via 2076:Recovery from an erroneous state 1465: 797:, the first member of Digital's 700:Booting the first microcomputers 507: 5325: 5300: 5276: 5249: 5222: 5196: 5165: 5138: 5050: 5026: 5006: 4995:from the original on 2014-12-23 4973: 4962:from the original on 2020-11-12 4944: 4933:from the original on 2013-03-18 4919: 4908:from the original on 2011-08-21 4894: 4857:from the original on 2017-10-06 4786:from the original on 2017-10-06 4741:from the original on 2017-10-06 4699:from the original on 2019-07-25 4513:from the original on 2022-10-09 4489: 4475:from the original on 2022-10-09 4455: 4440:from the original on 2022-10-09 4416: 4405:from the original on 2021-11-13 4391: 4380:from the original on 2016-10-05 4358: 4336: 4325:from the original on 2023-02-20 4307: 4296:from the original on 2020-11-11 4278: 4267:from the original on 2010-12-28 4253: 4231: 4206: 4195:from the original on 2022-10-09 4158:from the original on 2017-08-24 4079: 4068: 4040: 4014: 4003:from the original on 2022-10-09 3967: 3937: 3907: 3877: 3847: 3823: 3805: 3775: 3745: 3715: 3704:from the original on 2022-10-24 3687:Microcomputer Products Handbook 3677: 3666:from the original on 2022-10-24 3649:Microcomputer Products Handbook 3639: 3609: 3598:. March 1981. EK-M9312-TM-OO3. 3579: 3549: 3519: 3508:from the original on 2019-07-30 3491: 3480:from the original on 2020-01-03 3466: 3412:PDP-15 Systems Reference Manual 3403: 3373: 3343: 3313: 3283: 3272:from the original on 2022-10-09 3199:from the original on 2022-10-09 3173: 3162:from the original on 2022-10-09 3136: 3106: 3076: 3050: 3030: 3000: 2970: 2940: 2921: 2910:from the original on 2022-10-09 2888: 2811:from the original on 2023-02-20 2738:from the original on 2012-04-17 2709:from the original on 2020-05-10 2680:from the original on 2018-10-05 2670:"Pull oneself up by bootstraps" 2651:from the original on 2006-08-27 2620:from the original on 2019-08-05 2358: 2337: 2328: 2318: 2060:Detection of an erroneous state 1291: 5256:Hollister, Sean (2021-10-19). 4754:boot sector searches for the 4562:; Perez, Gary; Peters, Chris; 4243:Windows NT Server Resource Kit 4183:"BIOS Boot Specification 1.01" 3724:PDP-11/34 system user's manual 3568:. June 1977. EK-M9301-TM-OO1. 2928:From Gutenberg to the Internet 2822: 2779: 2749: 2720: 2691: 2662: 2631: 2602: 2305: 2204:Bootstrapping § Computing 2173:On 19 July 2024, an update of 1274:Trivial File Transfer Protocol 27:Process of starting a computer 13: 1: 6181:Preboot Execution Environment 5786:Run-Time Abstraction Services 5332:Peckham, James (2022-03-29). 5229:Paul Wagenseil (2021-01-21). 5135:Reddit update, 20 000 replies 5094:IEEE Xplore: 27 December 2004 4685:Rosch, Winn L. (1991-02-12). 3954:Digital Equipment Corporation 3924:Digital Equipment Corporation 3894:Digital Equipment Corporation 3864:Digital Equipment Corporation 3792:Digital Equipment Corporation 3762:Digital Equipment Corporation 3732:Digital Equipment Corporation 3695:Digital Equipment Corporation 3657:Digital Equipment Corporation 3626:Digital Equipment Corporation 3596:Digital Equipment Corporation 3566:Digital Equipment Corporation 3536:Digital Equipment Corporation 3445:How To Use The Nova Computers 3420:Digital Equipment Corporation 3390:Digital Equipment Corporation 3360:Digital Equipment Corporation 3330:Digital Equipment Corporation 3300:Digital Equipment Corporation 3190:Digital Equipment Corporation 2674:Idioms by The Free Dictionary 2595: 2180:s Falcon software caused the 2169:LG smartphone bootloop issues 2022:a concurrent and distributed 1817:Other kinds of boot sequences 1708:Extended BIOS Parameter Block 1513:on 16-bit x86 processors and 1509:(the physical memory address 1505:, the instruction located at 1493:BIOS from 2000 during booting 1281:Preboot Execution Environment 676:Check paper tape reader ready 639:Check paper tape reader ready 525:Digital Equipment Corporation 420:IBM coined this term for the 399:IBM System/360 and successors 85:(CPU) has no software in its 69:is the process of starting a 5640:MultiProcessor Specification 5184:(2). Element K Journals: 9. 4799:boot sector loads the whole 3474:"Oldcomputers: Altair 8800b" 1566:non-volatile storage devices 793:as a console processor; the 150:and derives from the phrase 7: 6211:Remote Initial Program Load 5808:Common Firmware Environment 4245:. Microsoft. Archived from 3322:PDP-11 Peripherals Handbook 3125:. August 1963. p. 53. 2196: 2108: 2014:that is stuck in a bootloop 1994: 1966: 1963:that are hostile to users. 1932: 1648:on disk (also known as the 927:-based machines, including 489:, and to search for record 10: 6369: 5800:Hybrid firmware bootloader 5541: 5381:Baran, Guru (2024-07-19). 5307:Hager, Ryne (2020-06-01). 4343:Brown, Eric (2008-10-02). 3332:. 1976. p. 4-25. 3095:. p. 10. A22-6741-1. 2224:Comparison of boot loaders 1435:keys during the POST; the 1392:For example, on a PC with 1297: 1257: 991:Comparison of boot loaders 988: 853:Software Cracking: History 745:erasable programmable ROMs 220:First commercial computers 163: 43: 36: 29: 6266: 6227: 6170: 6134: 6086: 6079: 6045: 6013: 5849:Comparison of bootloaders 5831: 5799: 5684: 5594: 5562: 5552: 5493: 5161:– via Google Books. 4213:Red Hat Bootloader Team. 3039:Oxford English Dictionary 2903:. IBM. 1953. p. 26. 2579:(DPT/FDPB). Therefore, a 2508:sectors had to resort to 2182:2024 CrowdStrike incident 2099:zero trust security model 1951:unlocking the boot loader 1848:digital signal processors 1758:from the storage device. 1689:Advanced Active Partition 1640:, found as byte sequence 1162:Second-stage boot loaders 673:Set the P register to 106 651:If end of tape, jump to 9 287:from a punched card in a 4711:has been improved under 3123:Control Data Corporation 2841:Proceedings of the I.R.E 2524:, multi-level data/code 2381:The signature at offset 2370:Second-stage boot loader 2270: 1311:bootable flash drive, a 1118:First-stage boot loaders 981:x86-based workstations. 977:-based machines and the 877:Some machines, like the 688:Decrement the P register 654:Increment the P register 428:button. On the high end 326:Another example was the 216:and then executed them. 5737:Phoenix SecureCore UEFI 4401:. YouTube. 2008-07-16. 3192:. 1969. pp. 2–72. 2773:10.1109/mahc.1980.10009 2264:Windows startup process 2151:during conversion from 1797:Unlike BIOS, UEFI (not 1777: 1571: 1217:List of PC Booter games 967:Advanced RISC Computing 872:BeOS Personal Edition 5 831:'s first computer, the 785:Some minicomputers and 679:If not ready, jump to 2 642:If not ready, jump to 2 636:Set the P register to 9 374:The first model of the 291:, a magnetic tape in a 83:central processing unit 5151:. Wiley. p. 257. 5107:Tim Warren, The Verge 4050:; Kane, Gerry (1981). 3977:; Kane, Gerry (1981). 2757:Campbell-Kelly, Martin 2699:"Bootstrap Definition" 2516:-level programming in 2492:, for the addition of 2057: 2015: 1836: 1691:(18 bytes) or special 1494: 1483: 1447:keys during the POST. 1316: 979:SGI Visual Workstation 965:-based computers. The 845:Apple DOS: Boot loader 728: 517: 315: 269: 177: 123:does. Minimally, some 58: 5192:– via ProQuest. 4927:"OpenBIOS - coreboot" 4816:utility to work. The 3362:. 1965. p. 143. 3230:Burroughs Corporation 2868:"IBM 7619 Exchange". 2229:Linux startup process 2052: 2002: 1975:Android Verified boot 1826: 1782:Many modern systems ( 1489: 1473: 1307: 1240:GPS navigation device 1204:dual or multi-booting 1148:Partition Boot Record 1096:Partition Boot Record 901:IBM Personal Computer 719: 515: 458:Channel Command Words 313: 263: 171: 56: 46:Boot (disambiguation) 6056:EFI system partition 6022:GUID Partition Table 5972:Windows Boot Manager 5842:Bootloader unlocking 5654:Legacy Plug and Play 5578:Open-source firmware 5571:Proprietary firmware 5178:Windows Professional 5038:mjg59.dreamwidth.org 4319:www.tomshardware.com 3839:] (in Italian). 3628:. 1981. p. 17. 3528:BM873 restart/loader 3145:GE-645 System Manual 2577:Disk Parameter Table 2560:will load the whole 2441:PC DOS 5.0 2103:blue screen of death 2066:Blue screen of death 1846:) or sometimes even 1811:EFI System Partition 1403:in order to try out 1005:random-access memory 737:mask-programmed ROMs 545:magnetic-core memory 523:, starting with the 414:Initial Program Load 353:peripheral processor 44:For other uses, see 6063:BIOS boot partition 6036:Apple Partition Map 5867:Acronis OS Selector 5707:American Megatrends 5387:Cyber Security News 5119:Joe Tidy, BBC News 4952:"UEFI - OSDev Wiki" 4152:Glamenv-Septzen.net 3812:Ciaramella, Alberto 3382:PDP-9 User Handbook 3121:(Second ed.). 2644:The Free Dictionary 2510:self-modifying code 2385:in boot sectors is 1829:unlocked bootloader 1768:BIOS interrupt call 1704:Volume Boot Records 1001:non-volatile memory 985:Modern boot loaders 466:Program Status Word 440:-like device or an 6324:Power-on self-test 6029:Master boot record 4347:. linuxdevices.com 4290:www.disk-image.com 4215:"UEFI shim loader" 2959:. pp. 14–15. 2787:Wilkes, Maurice V. 2472:compared to their 2430:misinterpretation. 2016: 1990:Firmware passwords 1837: 1669:Master Boot Record 1650:MBR boot signature 1625:Volume Boot Record 1605:Master Boot Record 1535:power-on self-test 1495: 1484: 1413:Power-on self-test 1372:floppy disk drives 1364:memory card reader 1345:optical disc drive 1341:Master Boot Record 1317: 1236:digital television 1144:Master Boot Record 1106:size, track size. 1092:Master Boot Record 1066:(for example, the 909:power-on self test 787:superminicomputers 778:, a researcher at 776:Alberto Ciaramella 729: 558:(1969), and DEC's 518: 316: 270: 178: 59: 6340: 6339: 6166: 6165: 6014:Partition layouts 6009: 6008: 5993:Plop Boot Manager 5795: 5794: 4989:Texas Instruments 4731:"FAT32 in DR-DOS" 4659:978-0-201-60835-9 4566:; Pollock, John; 4504:Intel Corporation 3044:Oxford University 2791:Wheeler, David J. 2732:The Phrase Finder 2486:assembly language 2482:code optimization 2259:Self-booting disk 2234:Macintosh startup 2186:Microsoft Windows 2040:§ erroneous state 2024:system of systems 1615:flag set). If an 1501:CPU, executes in 1329:solid-state drive 935:Unix workstations 913:IBM PC compatible 851:mechanisms. (See 763:The Data General 741:programmable ROMs 663:Teletype Model 33 556:Data General Nova 332:IBM 7040 and 7044 206:stepping switches 73:as initiated via 16:(Redirected from 6360: 6333: 6326: 6319: 6312: 6305: 6298: 6296:Execute in place 6291: 6284: 6277: 6259: 6252: 6245: 6238: 6220: 6213: 6206: 6197: 6190: 6183: 6159: 6152: 6145: 6125: 6118: 6111: 6104: 6097: 6084: 6083: 6072: 6065: 6058: 6038: 6031: 6024: 6002: 5995: 5988: 5981: 5974: 5967: 5960: 5953: 5946: 5939: 5932: 5925: 5918: 5911: 5904: 5897: 5890: 5883: 5876: 5869: 5856: 5855: 5851: 5844: 5824: 5817: 5810: 5788: 5781: 5774: 5767: 5760: 5753: 5746: 5744:TianoCore EDK II 5739: 5732: 5723: 5716: 5709: 5702: 5695: 5677: 5670: 5663: 5656: 5649: 5642: 5635: 5628: 5619: 5612: 5605: 5587: 5580: 5573: 5560: 5559: 5547: 5534: 5527: 5518: 5511: 5504: 5476: 5469: 5462: 5453: 5452: 5446: 5445: 5443: 5442: 5427: 5421: 5420: 5418: 5417: 5411:www.eye.security 5403: 5397: 5396: 5394: 5393: 5378: 5372: 5371: 5369: 5368: 5354: 5348: 5347: 5345: 5344: 5329: 5323: 5322: 5320: 5319: 5304: 5298: 5297: 5295: 5294: 5280: 5274: 5273: 5271: 5270: 5253: 5247: 5246: 5244: 5243: 5226: 5220: 5219: 5217: 5216: 5209:BleepingComputer 5200: 5194: 5193: 5169: 5163: 5162: 5142: 5136: 5129: 5123: 5117: 5111: 5105: 5096: 5083: 5074: 5073: 5071: 5070: 5063:BleepingComputer 5054: 5048: 5047: 5045: 5044: 5030: 5024: 5023: 5021: 5020: 5010: 5004: 5003: 5001: 5000: 4977: 4971: 4970: 4968: 4967: 4948: 4942: 4941: 4939: 4938: 4929:. coreboot.org. 4923: 4917: 4916: 4914: 4913: 4898: 4892: 4891: 4863: 4862: 4842: 4836: 4835: 4792: 4791: 4771: 4765: 4764: 4747: 4746: 4726: 4720: 4718: 4705: 4704: 4682: 4676: 4663: 4641: 4630: 4628: 4613: 4580:Petzold, Charles 4564:Petzold, Charles 4532: 4526: 4525: 4519: 4518: 4512: 4501: 4493: 4487: 4486: 4481: 4480: 4474: 4467: 4459: 4453: 4452: 4446: 4445: 4439: 4428: 4420: 4414: 4413: 4411: 4410: 4395: 4389: 4388: 4386: 4385: 4366:Larabel, Michael 4362: 4356: 4355: 4353: 4352: 4340: 4334: 4333: 4331: 4330: 4311: 4305: 4304: 4302: 4301: 4282: 4276: 4275: 4273: 4272: 4257: 4251: 4250: 4235: 4229: 4228: 4226: 4225: 4210: 4204: 4203: 4201: 4200: 4194: 4187: 4178: 4167: 4166: 4164: 4163: 4143: 4137: 4134: 4132: 4131: 4122:. Archived from 4115: 4100: 4099: 4097: 4096: 4091: 4083: 4077: 4072: 4066: 4065: 4044: 4038: 4037: 4035: 4028: 4018: 4012: 4011: 4009: 4008: 4002: 3985: 3971: 3965: 3964: 3962: 3951: 3941: 3935: 3934: 3932: 3921: 3911: 3905: 3904: 3902: 3891: 3881: 3875: 3874: 3872: 3861: 3851: 3845: 3844: 3827: 3821: 3819: 3809: 3803: 3802: 3800: 3789: 3779: 3773: 3772: 3770: 3759: 3749: 3743: 3742: 3740: 3729: 3719: 3713: 3712: 3710: 3709: 3703: 3692: 3681: 3675: 3674: 3672: 3671: 3665: 3654: 3643: 3637: 3636: 3634: 3623: 3613: 3607: 3606: 3604: 3593: 3583: 3577: 3576: 3574: 3563: 3553: 3547: 3546: 3544: 3533: 3523: 3517: 3516: 3514: 3513: 3495: 3489: 3488: 3486: 3485: 3470: 3464: 3463: 3461: 3450: 3440: 3431: 3430: 3428: 3417: 3407: 3401: 3400: 3398: 3387: 3377: 3371: 3370: 3368: 3357: 3347: 3341: 3340: 3338: 3327: 3317: 3311: 3310: 3308: 3297: 3287: 3281: 3280: 3278: 3277: 3271: 3260: 3250: 3241: 3240: 3238: 3227: 3217: 3208: 3207: 3205: 3204: 3198: 3187: 3177: 3171: 3170: 3168: 3167: 3161: 3155:. January 1968. 3153:General Electric 3150: 3140: 3134: 3133: 3131: 3120: 3110: 3104: 3103: 3101: 3090: 3080: 3074: 3073: 3071: 3064: 3054: 3048: 3047: 3034: 3028: 3027: 3025: 3014: 3004: 2998: 2997: 2995: 2984: 2974: 2968: 2967: 2965: 2954: 2944: 2938: 2925: 2919: 2918: 2916: 2915: 2909: 2902: 2892: 2886: 2885: 2883: 2876: 2865: 2856: 2855: 2853: 2838: 2830:Buchholz, Werner 2826: 2820: 2819: 2817: 2816: 2783: 2777: 2776: 2753: 2747: 2746: 2744: 2743: 2724: 2718: 2717: 2715: 2714: 2695: 2689: 2688: 2686: 2685: 2666: 2660: 2659: 2657: 2656: 2635: 2629: 2628: 2626: 2625: 2606: 2589: 2581:DR-DOS 7.07 2551: 2545: 2528:and algorithmic 2518:machine language 2462: 2453: 2437: 2431: 2424: 2417:in programs for 2416: 2404: 2400: 2396: 2392: 2388: 2384: 2379: 2373: 2366:active partition 2362: 2356: 2341: 2335: 2332: 2326: 2322: 2316: 2309: 2297: 2286: 2179: 1972:UEFI secure boot 1865:USB flash drives 1753: 1749: 1728: 1661:removable drives 1647: 1643: 1639: 1617:active partition 1602: 1598: 1594: 1590: 1579: 1516: 1512: 1266:computer network 1232:embedded systems 1044:bootstrap loader 1021:execute in place 1019:) which support 1011:(ROM, and later 1009:read-only memory 941:later developed 939:Sun Microsystems 733:read-only memory 578:read-only memory 496: 492: 488: 484: 480: 476: 471: 463: 369:read-only memory 346:(c. 1964) had a 251:IBM 7030 Stretch 158:read-only memory 125:embedded systems 110:operating system 108:, typically the 32:Quickboot (QEMM) 21: 6368: 6367: 6363: 6362: 6361: 6359: 6358: 6357: 6343: 6342: 6341: 6336: 6329: 6322: 6315: 6308: 6301: 6294: 6287: 6280: 6273: 6262: 6255: 6248: 6241: 6234: 6223: 6216: 6209: 6202: 6193: 6186: 6179: 6162: 6155: 6148: 6141: 6130: 6121: 6114: 6107: 6100: 6093: 6075: 6068: 6061: 6054: 6041: 6034: 6027: 6020: 6005: 5998: 5991: 5984: 5977: 5970: 5963: 5956: 5949: 5942: 5935: 5928: 5921: 5914: 5907: 5900: 5893: 5886: 5879: 5872: 5865: 5859:Implementations 5854: 5847: 5840: 5827: 5820: 5813: 5806: 5791: 5784: 5777: 5770: 5763: 5756: 5749: 5742: 5735: 5728: 5719: 5712: 5705: 5698: 5691: 5685:Implementations 5680: 5673: 5666: 5659: 5652: 5645: 5638: 5631: 5624: 5615: 5608: 5601: 5590: 5585:Custom firmware 5583: 5576: 5569: 5548: 5539: 5530: 5523: 5514: 5507: 5500: 5489: 5480: 5450: 5449: 5440: 5438: 5429: 5428: 5424: 5415: 5413: 5405: 5404: 5400: 5391: 5389: 5379: 5375: 5366: 5364: 5362:crowdstrike.com 5356: 5355: 5351: 5342: 5340: 5330: 5326: 5317: 5315: 5305: 5301: 5292: 5290: 5282: 5281: 5277: 5268: 5266: 5254: 5250: 5241: 5239: 5227: 5223: 5214: 5212: 5202: 5201: 5197: 5170: 5166: 5159: 5143: 5139: 5130: 5126: 5118: 5114: 5106: 5099: 5084: 5077: 5068: 5066: 5056: 5055: 5051: 5042: 5040: 5032: 5031: 5027: 5018: 5016: 5012: 5011: 5007: 4998: 4996: 4979: 4978: 4974: 4965: 4963: 4950: 4949: 4945: 4936: 4934: 4925: 4924: 4920: 4911: 4909: 4900: 4899: 4895: 4860: 4858: 4843: 4839: 4789: 4787: 4780:opendos@delorie 4772: 4768: 4744: 4742: 4735:opendos@delorie 4727: 4723: 4713:DR DOS 5.0 4702: 4700: 4683: 4679: 4660: 4642: 4633: 4615: 4594: 4584:Microsoft Press 4568:Reynolds, Aaron 4536:Zbikowski, Mark 4533: 4529: 4516: 4514: 4510: 4499: 4495: 4494: 4490: 4478: 4476: 4472: 4465: 4461: 4460: 4456: 4443: 4441: 4437: 4426: 4422: 4421: 4417: 4408: 4406: 4397: 4396: 4392: 4383: 4381: 4363: 4359: 4350: 4348: 4341: 4337: 4328: 4326: 4313: 4312: 4308: 4299: 4297: 4284: 4283: 4279: 4270: 4268: 4259: 4258: 4254: 4237: 4236: 4232: 4223: 4221: 4211: 4207: 4198: 4196: 4192: 4185: 4179: 4170: 4161: 4159: 4144: 4140: 4129: 4127: 4116: 4103: 4094: 4092: 4089: 4085: 4084: 4080: 4073: 4069: 4062: 4045: 4041: 4033: 4026: 4020: 4019: 4015: 4006: 4004: 4000: 3994: 3983: 3972: 3968: 3960: 3949: 3943: 3942: 3938: 3930: 3919: 3913: 3912: 3908: 3900: 3889: 3883: 3882: 3878: 3870: 3859: 3853: 3852: 3848: 3829: 3828: 3824: 3815: 3810: 3806: 3798: 3787: 3781: 3780: 3776: 3768: 3757: 3751: 3750: 3746: 3738: 3727: 3721: 3720: 3716: 3707: 3705: 3701: 3690: 3683: 3682: 3678: 3669: 3667: 3663: 3652: 3645: 3644: 3640: 3632: 3621: 3615: 3614: 3610: 3602: 3591: 3585: 3584: 3580: 3572: 3561: 3555: 3554: 3550: 3542: 3531: 3525: 3524: 3520: 3511: 3509: 3498:Holmer, Glenn. 3496: 3492: 3483: 3481: 3472: 3471: 3467: 3459: 3448: 3442: 3441: 3434: 3426: 3415: 3409: 3408: 3404: 3396: 3385: 3379: 3378: 3374: 3366: 3355: 3349: 3348: 3344: 3336: 3325: 3319: 3318: 3314: 3306: 3295: 3289: 3288: 3284: 3275: 3273: 3269: 3258: 3252: 3251: 3244: 3236: 3225: 3219: 3218: 3211: 3202: 3200: 3196: 3185: 3179: 3178: 3174: 3165: 3163: 3159: 3148: 3142: 3141: 3137: 3129: 3118: 3112: 3111: 3107: 3099: 3088: 3082: 3081: 3077: 3069: 3062: 3056: 3055: 3051: 3036: 3035: 3031: 3023: 3019:. p. 146. 3012: 3006: 3005: 3001: 2993: 2982: 2976: 2975: 2971: 2963: 2952: 2946: 2945: 2941: 2926: 2922: 2913: 2911: 2907: 2900: 2894: 2893: 2889: 2881: 2874: 2867: 2866: 2859: 2851: 2836: 2827: 2823: 2814: 2812: 2784: 2780: 2754: 2750: 2741: 2739: 2726: 2725: 2721: 2712: 2710: 2697: 2696: 2692: 2683: 2681: 2668: 2667: 2663: 2654: 2652: 2637: 2636: 2632: 2623: 2621: 2608: 2607: 2603: 2598: 2593: 2592: 2552: 2548: 2463: 2456: 2438: 2434: 2422: 2414: 2402: 2398: 2394: 2390: 2386: 2382: 2380: 2376: 2363: 2359: 2342: 2338: 2333: 2329: 2323: 2319: 2310: 2306: 2301: 2300: 2287: 2278: 2273: 2268: 2249:Network booting 2199: 2177: 2111: 2087: 2085:Recovery policy 2078: 2062: 1997: 1987:Disk encryption 1984:Intel BootGuard 1969: 1957:Matthew Garrett 1935: 1872:embedded system 1819: 1803:EFI application 1780: 1751: 1747: 1724: 1673:partition table 1645: 1641: 1637: 1600: 1596: 1592: 1588: 1577: 1574: 1514: 1510: 1468: 1446: 1442: 1434: 1430: 1360:USB flash drive 1333:hard disk drive 1302: 1294: 1289: 1262: 1260:Network booting 1256: 1254:Network booting 1228: 1164: 1120: 997: 987: 915:computers. The 849:copy protection 814: 761: 714: 702: 618: 510: 494: 490: 486: 482: 478: 474: 469: 461: 401: 222: 191: 189:Early computers 186: 166: 49: 42: 35: 28: 23: 22: 15: 12: 11: 5: 6366: 6356: 6355: 6338: 6337: 6335: 6334: 6327: 6320: 6313: 6306: 6299: 6292: 6285: 6278: 6270: 6268: 6264: 6263: 6261: 6260: 6253: 6246: 6239: 6231: 6229: 6225: 6224: 6222: 6221: 6214: 6207: 6200: 6199: 6198: 6191: 6176: 6174: 6168: 6167: 6164: 6163: 6161: 6160: 6153: 6146: 6138: 6136: 6132: 6131: 6129: 6128: 6127: 6126: 6112: 6105: 6098: 6090: 6088: 6081: 6077: 6076: 6074: 6073: 6066: 6059: 6051: 6049: 6043: 6042: 6040: 6039: 6032: 6025: 6017: 6015: 6011: 6010: 6007: 6006: 6004: 6003: 5996: 5989: 5982: 5975: 5968: 5961: 5954: 5947: 5940: 5933: 5926: 5919: 5912: 5905: 5898: 5891: 5884: 5877: 5870: 5862: 5860: 5853: 5852: 5845: 5837: 5835: 5829: 5828: 5826: 5825: 5818: 5811: 5803: 5801: 5797: 5796: 5793: 5792: 5790: 5789: 5782: 5775: 5768: 5761: 5754: 5747: 5740: 5733: 5726: 5725: 5724: 5717: 5703: 5696: 5688: 5686: 5682: 5681: 5679: 5678: 5671: 5664: 5657: 5650: 5643: 5636: 5629: 5622: 5621: 5620: 5606: 5598: 5596: 5592: 5591: 5589: 5588: 5581: 5574: 5566: 5564: 5557: 5550: 5549: 5542: 5540: 5538: 5537: 5536: 5535: 5521: 5520: 5519: 5512: 5497: 5495: 5491: 5490: 5479: 5478: 5471: 5464: 5456: 5448: 5447: 5422: 5398: 5373: 5349: 5338:Android Police 5324: 5313:Android Police 5299: 5275: 5248: 5221: 5195: 5164: 5157: 5137: 5124: 5112: 5097: 5075: 5049: 5025: 5005: 4991:. 2013-12-05. 4972: 4956:wiki.osdev.org 4943: 4918: 4893: 4837: 4766: 4721: 4677: 4658: 4631: 4592: 4576:Letwin, Gordon 4552:McDonald, Marc 4544:Ballmer, Steve 4527: 4488: 4454: 4415: 4390: 4368:(2008-06-14). 4357: 4335: 4306: 4277: 4252: 4249:on 2007-05-15. 4230: 4205: 4168: 4138: 4101: 4078: 4067: 4060: 4039: 4013: 3992: 3966: 3936: 3906: 3876: 3846: 3822: 3804: 3774: 3744: 3714: 3676: 3638: 3608: 3578: 3548: 3518: 3490: 3465: 3432: 3402: 3372: 3342: 3312: 3282: 3242: 3209: 3172: 3135: 3105: 3075: 3049: 3029: 2999: 2989:. p. 34. 2969: 2939: 2920: 2887: 2857: 2821: 2805:Addison-Wesley 2778: 2748: 2719: 2690: 2661: 2630: 2600: 2599: 2597: 2594: 2591: 2590: 2546: 2484:techniques in 2454: 2432: 2374: 2368:may contain a 2357: 2336: 2327: 2317: 2303: 2302: 2299: 2298: 2275: 2274: 2272: 2269: 2267: 2266: 2261: 2256: 2251: 2246: 2241: 2236: 2231: 2226: 2221: 2216: 2211: 2206: 2200: 2198: 2195: 2194: 2193: 2171: 2166: 2160: 2149:rounding error 2138: 2132: 2127: 2125:Windows Server 2122: 2117: 2115:Windows NT 4.0 2110: 2107: 2095:Single sign-on 2086: 2083: 2077: 2074: 2061: 2058: 1996: 1993: 1992: 1991: 1988: 1985: 1982: 1979: 1976: 1973: 1968: 1965: 1934: 1931: 1912:host processor 1818: 1815: 1779: 1776: 1687:(6 bytes), an 1685:disk timestamp 1681:disk signature 1677:boot signature 1611:(the one with 1573: 1570: 1491:Award Software 1467: 1464: 1444: 1440: 1432: 1428: 1293: 1290: 1288: 1285: 1258:Main article: 1255: 1252: 1227: 1224: 1192:device drivers 1163: 1160: 1146:(MBR) and the 1119: 1116: 1100:IBM System/360 1094:(MBR) and the 986: 983: 829:Apple Computer 813: 810: 760: 757: 720:An Intel 2708 713: 710: 701: 698: 693: 692: 689: 686: 683: 680: 677: 674: 659: 658: 655: 652: 649: 646: 643: 640: 637: 617: 614: 509: 506: 422:7030 (Stretch) 409:z/Architecture 405:IBM System/360 400: 397: 381: 380: 372: 361: 221: 218: 190: 187: 185: 182: 165: 162: 148:bootstrap load 129:state machines 106:runtime system 26: 9: 6: 4: 3: 2: 6365: 6354: 6351: 6350: 6348: 6332: 6328: 6325: 6321: 6318: 6314: 6311: 6307: 6304: 6300: 6297: 6293: 6290: 6286: 6283: 6279: 6276: 6272: 6271: 6269: 6265: 6258: 6254: 6251: 6247: 6244: 6240: 6237: 6233: 6232: 6230: 6226: 6219: 6215: 6212: 6208: 6205: 6201: 6196: 6192: 6189: 6185: 6184: 6182: 6178: 6177: 6175: 6173: 6169: 6158: 6154: 6151: 6147: 6144: 6140: 6139: 6137: 6133: 6124: 6120: 6119: 6117: 6113: 6110: 6106: 6103: 6099: 6096: 6092: 6091: 6089: 6085: 6082: 6078: 6071: 6067: 6064: 6060: 6057: 6053: 6052: 6050: 6048: 6044: 6037: 6033: 6030: 6026: 6023: 6019: 6018: 6016: 6012: 6001: 5997: 5994: 5990: 5987: 5983: 5980: 5976: 5973: 5969: 5966: 5962: 5959: 5955: 5952: 5948: 5945: 5941: 5938: 5934: 5931: 5927: 5924: 5920: 5917: 5913: 5910: 5906: 5903: 5899: 5896: 5895:BootX (Linux) 5892: 5889: 5888:BootX (Apple) 5885: 5882: 5878: 5875: 5871: 5868: 5864: 5863: 5861: 5857: 5850: 5846: 5843: 5839: 5838: 5836: 5834: 5830: 5823: 5819: 5816: 5812: 5809: 5805: 5804: 5802: 5798: 5787: 5783: 5780: 5776: 5773: 5769: 5766: 5762: 5759: 5755: 5752: 5748: 5745: 5741: 5738: 5734: 5731: 5727: 5722: 5718: 5715: 5711: 5710: 5708: 5704: 5701: 5697: 5694: 5690: 5689: 5687: 5683: 5676: 5672: 5669: 5665: 5662: 5658: 5655: 5651: 5648: 5644: 5641: 5637: 5634: 5630: 5627: 5626:Open Firmware 5623: 5618: 5614: 5613: 5611: 5607: 5604: 5600: 5599: 5597: 5593: 5586: 5582: 5579: 5575: 5572: 5568: 5567: 5565: 5561: 5558: 5556: 5551: 5546: 5533: 5529: 5528: 5526: 5522: 5517: 5513: 5510: 5506: 5505: 5503: 5499: 5498: 5496: 5492: 5488: 5484: 5477: 5472: 5470: 5465: 5463: 5458: 5457: 5454: 5436: 5432: 5426: 5412: 5408: 5402: 5388: 5384: 5377: 5363: 5359: 5353: 5339: 5335: 5328: 5314: 5310: 5303: 5289: 5285: 5279: 5265: 5264: 5259: 5252: 5238: 5237: 5232: 5225: 5211: 5210: 5205: 5199: 5191: 5187: 5183: 5179: 5175: 5168: 5160: 5158:9780471175025 5154: 5150: 5149: 5141: 5134: 5128: 5122: 5116: 5110: 5104: 5102: 5095: 5091: 5088: 5082: 5080: 5065: 5064: 5059: 5053: 5039: 5035: 5029: 5015: 5009: 4994: 4990: 4986: 4982: 4976: 4961: 4957: 4953: 4947: 4932: 4928: 4922: 4907: 4903: 4897: 4890: 4888: 4884: 4880: 4876: 4872: 4869: 4856: 4852: 4848: 4841: 4834: 4832: 4828: 4824: 4819: 4815: 4811: 4806: 4802: 4798: 4785: 4781: 4777: 4770: 4763: 4761: 4757: 4753: 4740: 4736: 4732: 4725: 4717: 4714: 4710: 4698: 4694: 4693: 4688: 4681: 4675: 4673: 4671: 4668: 4666: 4661: 4655: 4651: 4647: 4646:DOS Internals 4640: 4638: 4636: 4626: 4622: 4621:PCjs Machines 4618: 4611: 4607: 4603: 4599: 4595: 4593:1-55615-049-0 4589: 4585: 4581: 4577: 4573: 4569: 4565: 4561: 4560:Paterson, Tim 4557: 4553: 4549: 4545: 4541: 4537: 4531: 4524: 4509: 4505: 4498: 4492: 4485: 4471: 4464: 4458: 4451: 4436: 4432: 4425: 4419: 4404: 4400: 4394: 4379: 4375: 4371: 4367: 4361: 4346: 4339: 4324: 4320: 4316: 4310: 4295: 4291: 4287: 4281: 4266: 4262: 4256: 4248: 4244: 4240: 4234: 4220: 4216: 4209: 4191: 4184: 4177: 4175: 4173: 4157: 4153: 4149: 4142: 4136: 4126:on 2003-10-04 4125: 4121: 4114: 4112: 4110: 4108: 4106: 4088: 4082: 4076: 4071: 4063: 4061:0-931988-42-X 4057: 4053: 4049: 4048:Osborne, Adam 4043: 4032: 4025: 4024: 4017: 3999: 3995: 3993:0-931988-43-8 3989: 3982: 3981: 3976: 3975:Osborne, Adam 3970: 3959: 3955: 3948: 3947: 3940: 3929: 3925: 3918: 3917: 3910: 3899: 3895: 3888: 3887: 3880: 3869: 3865: 3858: 3857: 3850: 3842: 3838: 3834: 3833: 3826: 3818: 3813: 3808: 3797: 3793: 3786: 3785: 3778: 3767: 3763: 3756: 3755: 3748: 3737: 3733: 3726: 3725: 3718: 3700: 3696: 3689: 3688: 3680: 3662: 3658: 3651: 3650: 3642: 3631: 3627: 3620: 3619: 3612: 3601: 3597: 3590: 3589: 3582: 3571: 3567: 3560: 3559: 3552: 3541: 3537: 3530: 3529: 3522: 3507: 3503: 3502: 3494: 3479: 3475: 3469: 3458: 3454: 3447: 3446: 3439: 3437: 3425: 3421: 3414: 3413: 3406: 3395: 3391: 3384: 3383: 3376: 3365: 3361: 3354: 3353: 3346: 3335: 3331: 3324: 3323: 3316: 3305: 3301: 3294: 3293: 3286: 3268: 3264: 3257: 3256: 3249: 3247: 3235: 3231: 3224: 3223: 3216: 3214: 3195: 3191: 3184: 3183: 3176: 3158: 3154: 3147: 3146: 3139: 3128: 3124: 3117: 3116: 3109: 3098: 3094: 3087: 3086: 3079: 3068: 3061: 3060: 3053: 3045: 3041: 3040: 3033: 3022: 3018: 3011: 3010: 3003: 2992: 2988: 2981: 2980: 2973: 2962: 2958: 2951: 2950: 2943: 2937: 2936:0-930405-87-0 2933: 2929: 2924: 2906: 2899: 2898: 2891: 2880: 2873: 2872: 2864: 2862: 2850: 2846: 2842: 2835: 2831: 2825: 2810: 2806: 2802: 2801: 2796: 2795:Gill, Stanley 2792: 2788: 2782: 2774: 2770: 2766: 2762: 2758: 2752: 2737: 2733: 2729: 2723: 2708: 2704: 2700: 2694: 2679: 2675: 2671: 2665: 2650: 2646: 2645: 2640: 2634: 2619: 2615: 2611: 2605: 2601: 2587: 2582: 2578: 2575: 2571: 2567: 2563: 2559: 2556: 2550: 2543: 2539: 2535: 2531: 2527: 2523: 2519: 2515: 2511: 2507: 2503: 2499: 2495: 2491: 2487: 2483: 2479: 2475: 2471: 2467: 2461: 2459: 2451: 2447: 2442: 2436: 2428: 2420: 2412: 2408: 2407:little-endian 2378: 2371: 2367: 2361: 2354: 2350: 2346: 2340: 2331: 2321: 2314: 2308: 2304: 2295: 2294:recovery mode 2291: 2285: 2283: 2281: 2276: 2265: 2262: 2260: 2257: 2255: 2252: 2250: 2247: 2245: 2242: 2240: 2237: 2235: 2232: 2230: 2227: 2225: 2222: 2220: 2217: 2215: 2212: 2210: 2209:Multi-booting 2207: 2205: 2202: 2201: 2191: 2190:recovery mode 2187: 2184:resulting in 2183: 2176: 2172: 2170: 2167: 2164: 2161: 2158: 2154: 2150: 2146: 2142: 2139: 2137: 2133: 2131: 2128: 2126: 2123: 2121: 2118: 2116: 2113: 2112: 2106: 2104: 2100: 2096: 2092: 2082: 2073: 2071: 2067: 2056: 2051: 2049: 2045: 2041: 2037: 2033: 2030:(also called 2029: 2025: 2021: 2013: 2009: 2006:console of a 2005: 2001: 1989: 1986: 1983: 1980: 1977: 1974: 1971: 1970: 1964: 1962: 1958: 1954: 1952: 1948: 1944: 1940: 1930: 1928: 1924: 1919: 1917: 1913: 1907: 1904: 1902: 1897: 1891: 1889: 1884: 1881: 1877: 1873: 1868: 1866: 1861: 1857: 1853: 1849: 1845: 1842: 1834: 1830: 1825: 1821: 1814: 1812: 1808: 1804: 1800: 1795: 1793: 1789: 1785: 1775: 1774:via network. 1773: 1769: 1765: 1759: 1757: 1744: 1742: 1737: 1733: 1727: 1721: 1717: 1713: 1709: 1705: 1702: 1698: 1694: 1690: 1686: 1683:(6 bytes), a 1682: 1678: 1674: 1670: 1666: 1662: 1658: 1653: 1651: 1636: 1633: 1632:little-endian 1628: 1626: 1622: 1618: 1614: 1610: 1606: 1587: 1583: 1569: 1567: 1563: 1559: 1554: 1552: 1548: 1544: 1540: 1536: 1532: 1528: 1524: 1520: 1508: 1504: 1500: 1492: 1488: 1481: 1477: 1472: 1466:Boot sequence 1463: 1461: 1457: 1453: 1448: 1438: 1426: 1422: 1418: 1414: 1410: 1406: 1402: 1399: 1395: 1390: 1388: 1383: 1381: 1377: 1373: 1369: 1365: 1361: 1357: 1354: 1350: 1346: 1342: 1338: 1334: 1330: 1326: 1322: 1314: 1310: 1309:Windows To Go 1306: 1301: 1296: 1284: 1282: 1277: 1275: 1271: 1267: 1261: 1251: 1247: 1245: 1241: 1237: 1233: 1223: 1220: 1218: 1214: 1210: 1205: 1199: 1197: 1196:Open Firmware 1193: 1189: 1185: 1181: 1177: 1173: 1169: 1159: 1157: 1153: 1149: 1145: 1141: 1137: 1133: 1129: 1125: 1115: 1113: 1107: 1105: 1101: 1097: 1093: 1088: 1086: 1082: 1077: 1073: 1069: 1063: 1059: 1057: 1056:chain loading 1053: 1049: 1045: 1040: 1038: 1034: 1030: 1026: 1022: 1018: 1014: 1010: 1006: 1002: 996: 992: 982: 980: 976: 972: 968: 964: 960: 956: 952: 948: 944: 940: 936: 932: 930: 926: 922: 918: 914: 910: 906: 902: 897: 895: 891: 887: 883: 882:microcomputer 880: 875: 873: 869: 865: 862:systems from 861: 856: 854: 850: 846: 842: 837: 834: 830: 826: 824: 820: 809: 806: 804: 800: 796: 792: 788: 783: 781: 777: 772: 770: 766: 759:Minicomputers 756: 754: 750: 747:(EPROM), and 746: 742: 738: 734: 727: 726:circuit board 723: 718: 709: 707: 697: 690: 687: 684: 681: 678: 675: 672: 671: 670: 668: 664: 656: 653: 650: 647: 644: 641: 638: 635: 634: 633: 631: 627: 623: 622:Binary Loader 613: 611: 607: 603: 599: 595: 591: 586: 583: 579: 576: 571: 567: 565: 561: 557: 553: 548: 546: 542: 538: 534: 530: 526: 522: 521:Minicomputers 514: 508:Minicomputers 505: 502: 498: 467: 459: 455: 450: 447: 443: 439: 435: 432:models, most 431: 427: 423: 418: 416: 415: 410: 406: 396: 394: 389: 386: 377: 373: 370: 366: 362: 359: 355: 354: 349: 345: 341: 340: 339: 336: 333: 329: 324: 321: 312: 308: 306: 302: 298: 294: 290: 286: 282: 279: 275: 267: 262: 258: 256: 252: 248: 244: 243:magnetic tape 240: 239:magnetic drum 236: 231: 227: 217: 215: 211: 210:David Wheeler 207: 203: 198: 196: 181: 175: 170: 161: 159: 155: 154: 149: 145: 144: 140:is short for 139: 135: 132: 130: 126: 122: 118: 113: 111: 107: 103: 99: 94: 92: 88: 84: 80: 76: 72: 68: 64: 55: 51: 47: 40: 39:Bootstrapping 33: 19: 6228:ROM variants 6172:Network boot 6150:Raspberry Pi 5916:systemd-boot 5486: 5439:. Retrieved 5437:. 2024-07-19 5434: 5425: 5414:. Retrieved 5410: 5401: 5390:. Retrieved 5386: 5376: 5365:. Retrieved 5361: 5352: 5341:. Retrieved 5337: 5327: 5316:. Retrieved 5312: 5302: 5291:. Retrieved 5287: 5278: 5267:. Retrieved 5261: 5251: 5240:. Retrieved 5234: 5224: 5213:. Retrieved 5207: 5198: 5181: 5177: 5167: 5147: 5140: 5127: 5115: 5089: 5067:. Retrieved 5061: 5052: 5041:. Retrieved 5037: 5028: 5017:. Retrieved 5008: 4997:. Retrieved 4984: 4975: 4964:. Retrieved 4955: 4946: 4935:. Retrieved 4921: 4910:. Retrieved 4896: 4865: 4859:. Retrieved 4850: 4840: 4794: 4788:. Retrieved 4779: 4776:"Can't copy" 4769: 4749: 4743:. Retrieved 4734: 4724: 4707: 4701:. Retrieved 4690: 4680: 4645: 4620: 4571: 4530: 4521: 4515:. Retrieved 4491: 4483: 4477:. Retrieved 4457: 4448: 4442:. Retrieved 4418: 4407:. Retrieved 4393: 4382:. Retrieved 4360: 4349:. Retrieved 4338: 4327:. Retrieved 4318: 4309: 4298:. Retrieved 4289: 4280: 4269:. Retrieved 4263:. coreboot. 4255: 4247:the original 4242: 4233: 4222:. Retrieved 4218: 4208: 4197:. Retrieved 4160:. Retrieved 4151: 4141: 4128:. Retrieved 4124:the original 4093:. Retrieved 4081: 4070: 4051: 4042: 4022: 4016: 4005:. Retrieved 3979: 3969: 3945: 3939: 3915: 3909: 3885: 3879: 3855: 3849: 3836: 3831: 3825: 3807: 3783: 3777: 3753: 3747: 3723: 3717: 3706:. Retrieved 3686: 3679: 3668:. Retrieved 3648: 3641: 3617: 3611: 3587: 3581: 3557: 3551: 3527: 3521: 3510:. Retrieved 3500: 3493: 3482:. Retrieved 3468: 3453:Data General 3444: 3411: 3405: 3381: 3375: 3351: 3345: 3321: 3315: 3291: 3285: 3274:. Retrieved 3254: 3221: 3201:. Retrieved 3181: 3175: 3164:. Retrieved 3144: 3138: 3114: 3108: 3084: 3078: 3058: 3052: 3038: 3032: 3008: 3002: 2978: 2972: 2948: 2942: 2927: 2923: 2912:. Retrieved 2896: 2890: 2870: 2847:(10): 1273. 2844: 2840: 2824: 2813:. Retrieved 2799: 2781: 2764: 2760: 2751: 2740:. Retrieved 2731: 2722: 2711:. Retrieved 2702: 2693: 2682:. Retrieved 2673: 2664: 2653:. 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Retrieved 2613: 2604: 2549: 2522:side effects 2504:support the 2470:boot sectors 2435: 2377: 2360: 2339: 2330: 2320: 2307: 2120:Windows 2000 2088: 2079: 2063: 2053: 2046:process and 2043: 2035: 2031: 2027: 2017: 2010:router with 1978:Samsung Knox 1955: 1947:cryptography 1936: 1920: 1915: 1911: 1908: 1905: 1892: 1885: 1869: 1838: 1820: 1802: 1798: 1796: 1781: 1760: 1745: 1735: 1654: 1629: 1612: 1608: 1575: 1555: 1507:reset vector 1496: 1482:'s boot0 MBR 1451: 1449: 1417:boot manager 1409:dual booting 1391: 1386: 1384: 1356:mass storage 1318: 1295: 1292:Boot devices 1278: 1263: 1248: 1244:flash memory 1229: 1221: 1200: 1165: 1158:processors. 1121: 1108: 1089: 1064: 1060: 1051: 1047: 1043: 1041: 998: 933: 898: 876: 857: 838: 827: 815: 807: 784: 773: 762: 749:flash memory 730: 724:"chip" on a 703: 694: 660: 621: 619: 587: 575:diode matrix 572: 568: 549: 536: 519: 503: 499: 451: 425: 419: 413: 402: 382: 357: 352: 347: 337: 325: 317: 271: 223: 214:punched tape 199: 192: 179: 151: 147: 142: 137: 136: 133: 114: 95: 66: 60: 50: 6282:ROM hacking 6218:Wake-on-LAN 5881:BootManager 5833:Bootloaders 5236:Tom's Guide 4887:PC DOS 4827:PC DOS 4692:PC Magazine 4556:O'Rear, Bob 4548:Gates, Bill 4540:Allen, Paul 2767:(1): 7–36. 2639:"Bootstrap" 2610:"bootstrap" 2586:PC DOS 2526:overlapping 2478:PC DOS 2239:Microreboot 2175:CrowdStrike 2163:Google Nest 1799:Legacy boot 1772:remote boot 1701:superfloppy 1657:fixed disks 1621:boot sector 1547:Option ROMs 1539:main memory 1460:Latitude ON 1085:entry point 1081:boot sector 1052:boot loader 973:-based and 890:Spectre GCR 767:(1970) and 706:Altair 8800 667:teleprinter 562:(1962) and 541:front panel 393:front panel 289:card reader 285:main memory 121:hibernation 87:main memory 6317:Instant-on 6303:Devicetree 6143:Bus Pirate 6047:Partitions 5815:Das U-Boot 5700:Award BIOS 5617:Video BIOS 5595:Interfaces 5441:2024-07-19 5416:2024-07-19 5392:2024-07-19 5367:2024-07-19 5343:2022-05-19 5318:2022-05-19 5293:2022-05-19 5269:2022-05-17 5242:2022-05-20 5215:2022-05-17 5092:published 5069:2022-12-11 5043:2022-11-30 5019:2015-10-25 4999:2015-01-25 4966:2020-09-26 4937:2013-03-20 4912:2008-01-07 4861:2017-10-06 4805:IBMDOS.COM 4801:IBMBIO.COM 4790:2017-10-06 4760:DRBIOS.SYS 4756:IBMBIO.COM 4745:2017-10-06 4703:2019-07-26 4669:) Errata: 4517:2012-08-23 4479:2013-11-03 4444:2019-08-23 4409:2010-11-20 4384:2010-11-20 4351:2010-11-20 4329:2020-09-26 4300:2020-09-26 4271:2010-11-20 4224:2023-10-28 4199:2017-12-21 4162:2012-08-22 4130:2009-03-29 4095:2024-09-04 4007:2019-08-23 3708:2022-06-12 3670:2022-06-12 3512:2016-05-02 3484:2019-12-10 3276:2007-04-14 3203:2012-11-09 3166:2019-10-30 2914:2012-11-09 2815:2020-09-25 2742:2010-07-15 2713:2019-10-02 2703:Tech Terms 2684:2019-10-07 2655:2008-08-27 2624:2019-08-05 2596:References 2562:IBMBIO.COM 2544:scenarios. 2542:chain load 2538:multi-boot 2446:IBMBIO.COM 2427:big-endian 2401:at offset 2393:at offset 2389:, that is 2311:Including 2244:Multi boot 2141:Android 10 2130:Windows 10 1876:Das U-Boot 1809:or in the 1786:and newer 1784:Intel Macs 1693:multi-boot 1452:quick-boot 1437:BIOS Setup 1387:boot order 1376:Zip drives 1298:See also: 1213:memtest86+ 1140:Das U-Boot 1076:x86 series 995:Bootloader 989:See also: 795:VAX-11/780 791:Intel 8085 630:Pseudocode 594:paper tape 434:System/370 430:System/360 348:dead start 293:tape drive 255:System/360 235:punch card 18:Boot drive 6289:ROM image 6080:Utilities 5937:OpeniBoot 5779:Kickstart 5772:LinuxBoot 5765:Libreboot 5730:InsydeH2O 5721:AMI Aptio 5661:AlphaBIOS 5494:Processes 5263:The Verge 5190:191083238 4904:. Intel. 2574:relocated 2566:overwrite 2290:boot loop 2214:Boot disk 2145:luminance 2036:boot-loop 2032:boot loop 2020:debugging 1896:Atmel AVR 1756:OS kernel 1580:(usually 1515:FFFFFFF0h 1503:real mode 1456:Splashtop 1349:El Torito 1209:safe mode 1136:Libreboot 1048:bootstrap 1017:NOR flash 860:Macintosh 819:Intel x86 765:Nova 1200 691:Jump to 2 657:Jump to 2 610:Supernova 537:toggle in 385:Burroughs 257:in 1964. 143:bootstrap 98:rebooting 63:computing 6347:Category 6331:EDL mode 6310:Fastboot 6275:Boot ROM 6135:Hardware 6123:Heimdall 6109:UEFITool 6095:flashrom 6087:Software 5965:SYSLINUX 5902:GNU GRUB 5758:Coreboot 5751:OpenBIOS 5555:firmware 5553:Booting 5483:Firmware 5288:The Week 5186:ProQuest 4993:Archived 4960:Archived 4931:Archived 4906:Archived 4855:Archived 4831:BOOT.LST 4784:Archived 4739:Archived 4697:Archived 4625:Archived 4610:16581341 4602:87-21452 4523:address. 4508:Archived 4470:Archived 4435:Archived 4403:Archived 4378:Archived 4374:Phoronix 4323:Archived 4294:Archived 4265:Archived 4190:Archived 4156:Archived 4031:Archived 3998:Archived 3958:Archived 3928:Archived 3898:Archived 3868:Archived 3841:Archived 3796:Archived 3766:Archived 3736:Archived 3699:Archived 3697:. 1985. 3661:Archived 3659:. 1985. 3630:Archived 3600:Archived 3570:Archived 3540:Archived 3506:Archived 3478:Archived 3457:Archived 3424:Archived 3394:Archived 3364:Archived 3334:Archived 3304:Archived 3267:Archived 3234:Archived 3194:Archived 3157:Archived 3127:Archived 3097:Archived 3067:Archived 3021:Archived 2991:Archived 2961:Archived 2905:Archived 2879:Archived 2849:Archived 2832:(1953). 2809:Archived 2797:(1951). 2736:Archived 2707:Archived 2678:Archived 2649:Archived 2618:Archived 2534:backward 2405:. 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5563:Types 5525:Linux 4871:FDISK 4511:(PDF) 4500:(PDF) 4473:(PDF) 4466:(PDF) 4438:(PDF) 4431:Intel 4427:(PDF) 4193:(PDF) 4186:(PDF) 4090:(PDF) 4034:(PDF) 4027:(PDF) 4001:(PDF) 3984:(PDF) 3961:(PDF) 3950:(PDF) 3931:(PDF) 3920:(PDF) 3901:(PDF) 3890:(PDF) 3871:(PDF) 3860:(PDF) 3835:[ 3799:(PDF) 3788:(PDF) 3769:(PDF) 3758:(PDF) 3739:(PDF) 3728:(PDF) 3702:(PDF) 3691:(PDF) 3664:(PDF) 3653:(PDF) 3633:(PDF) 3622:(PDF) 3603:(PDF) 3592:(PDF) 3573:(PDF) 3562:(PDF) 3543:(PDF) 3532:(PDF) 3460:(PDF) 3449:(PDF) 3427:(PDF) 3416:(PDF) 3397:(PDF) 3386:(PDF) 3367:(PDF) 3356:(PDF) 3337:(PDF) 3326:(PDF) 3307:(PDF) 3296:(PDF) 3270:(PDF) 3259:(PDF) 3237:(PDF) 3226:(PDF) 3197:(PDF) 3186:(PDF) 3160:(PDF) 3149:(PDF) 3130:(PDF) 3119:(PDF) 3100:(PDF) 3089:(PDF) 3070:(PDF) 3063:(PDF) 3024:(PDF) 3013:(PDF) 2994:(PDF) 2983:(PDF) 2964:(PDF) 2953:(PDF) 2908:(PDF) 2901:(PDF) 2882:(PDF) 2875:(PDF) 2852:(PDF) 2837:(PDF) 2570:stack 2498:FAT32 2423:55AAh 2415:AA55h 2403:+1FFh 2395:+1FEh 2383:+1FEh 2271:Notes 2178:' 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Index

Boot drive
Quickboot (QEMM)
Bootstrapping
Boot (disambiguation)

computing
computer
hardware
software
central processing unit
main memory
firmware
rebooting
RAM
runtime system
operating system
sleep
hibernation
embedded systems
state machines
bootstrap
to pull oneself up by one's bootstraps
read-only memory

ENIAC
ENIAC
EDSAC
stepping switches
David Wheeler
punched tape

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