The Multiface was a hardware peripheral released by Romantic Robot for several 1980s home computers . The primary function of the device was to dump the computer's memory to external storage . Pressing a red button on the Multiface activated it. As most games of the era did not have a save game feature, the Multiface allowed players to save their position by saving a loadable snapshot of the game. Home computer software of the early 1980s was typically loaded into RAM in one go, with copy protection measures concentrating the loading phase or just after it. The snapshot feature could be used after copy protection routines had been executed, to create a backup that was effectively unprotected against unauthorised distribution. Later models of the Multiface mitigated this by requiring the device to be present when re-loading the dumps into memory, making the dumps useless to people without a Multiface. Software producers also reacted to the threat by using routines that would prevent execution of the product if it detected that a Multiface was present and by loading the software in multiple parts, thus requiring the presence of the original, copy-protected media.
46-597: Pressing the red button on the Multiface raised the non-maskable interrupt line on the computer's processor, effectively taking control of the computer. The Multiface would then page in its own ROM, temporarily replacing the computer's operating system with that within the Multiface. Multifaces were released for 8-bit and 16-bit microcomputers, such as the ZX Spectrum , Amstrad CPC & Atari ST . Different models had slightly different features. The Multiface One
92-524: A Kempston joystick port, and later revisions contained a switch that effectively 'hid' the device from software. Early versions had a composite video out port but this feature was later removed. The Multiface Two was released for the Amstrad CPC range of computers and had similar features to the Multiface One, but added a button to reset the computer. Control of the visibility of the device
138-460: A non-maskable interrupt ( NMI ) is a hardware interrupt that standard interrupt-masking techniques in the system cannot ignore. It typically occurs to signal attention for non-recoverable hardware errors . Some NMIs may be masked, but only by using proprietary methods specific to the particular NMI. With regard to SPARC , the non-maskable interrupt (NMI), despite having the highest priority among interrupts, can be prevented from occurring through
184-422: A system or object . This definition is the basis of operation for many types of control systems , in which error is defined as the difference between a set point and the process value. An example of this would be the thermostat in a home heating system – the operation of the heating equipment is controlled by the difference (the error) between the thermostat setting and the sensed air temperature. Another approach
230-641: A trial court or some other court of first instance in applying the law in a particular legal case . This may involve such mistakes as improper admission of evidence , inappropriate instructions to the jury , or applying the wrong standard of proof . A stock market error is a stock market transaction that was done due to an error, due to human failure or computer errors . Within United States government intelligence agencies, such as Central Intelligence Agency agencies, error refers to intelligence error , as previous assumptions that used to exist at
276-448: A 'thru-port', for £49.95 (equivalent to £177 in 2023), and one without, which cost £44.95 (equivalent to £152 in 2023). Both were later reduced to £29.95 (equivalent to £78 in 2023). The main feature of the Multiface 3 was its ability to save to +3 disk, a useful feature for +3 owners who wanted to avoid the long loading times of tapes. The Multiface ST and Multiface ST II were released for Atari's ST computers. They connected to
322-587: A button to generate an NMI, such as Romantic Robot's Multiface , were a popular accessory for 1980s 8-bit and 16-bit home computers. These peripherals had a small amount of ROM and an NMI button. Pressing the button transferred control to the software in the peripheral's ROM, allowing the suspended program to be saved to disk (very useful for tape-based games with no disk support, but also for saving games in progress), screenshots to be saved or printed, or values in memory to be manipulated—a cheating technique to acquire extra lives, for example. Not all computers provide
368-408: A dropped ball ( baseball error ) by a player in a baseball game. In statistics , an error (or residual ) is not a "mistake" but rather a difference between a computed, estimated, or measured value and the accepted true, specified, or theoretically correct value. In science and engineering in general, an error is defined as a difference between the desired and actual performance or behavior of
414-671: A mechanism for triggering NMIs; however, many machines (typically rackmount servers) provide a physical button specifically for this purpose. Other machines may expose this functionality via an expansion card. Miles Gordon Technology 's DISCiPLE and +D products for the ZX Spectrum featured an NMI-producing "magic button". On the Nintendo Entertainment System , an NMI is generated during each vertical blanking interval . Because these NMIs (often referred to as "vblank interrupts") occur at frequent, regular intervals, code that manipulates game graphics and audio
460-513: A number of forms, including the Apple Macintosh 's "programmers' button" , and certain key combinations on Sun workstations. With the introduction of Windows 2000 , Microsoft allowed the use of an NMI to cause a system to either break into a debugger , or dump the contents of memory to disk and reboot. Debugging NMIs have also been used by devices that allow leisure users and gamers to manipulate running programs. Devices which added
506-454: A senior intelligence level within senior intelligence agencies, but has since been disproven, and is sometimes eventually listed as unclassified, and therefore more available to the public and citizenry of the United States. The Freedom of information act provides American citizenry with a means to read intelligence reports that were mired in error. Per United States Central Intelligence Agency's website (as of August, 2008) intelligence error
SECTION 10
#1732790629590552-425: A special monitor program. From this program, a developer can inspect the machine's memory and examine the internal state of the program at the instant of its interruption. This also allows the debugging or diagnosing of computers which appear hung . In older architectures, NMIs were used for interrupts which were typically never disabled because of the required response time. They were hidden signals. Examples include
598-411: A stop sign because I was in a hurry, and wasn't concentrating, and the police stop me, that is a mistake. If, however, I try to park in an area with conflicting signs, and I get a ticket because I was incorrect on my interpretation of what the signs meant, that would be an error. The first time it would be an error. The second time it would be a mistake since I should have known better. In human behavior
644-450: A system can be latent design errors that may go unnoticed for years, until the right set of circumstances arises that cause them to become active. Other errors in engineered systems can arise due to human error , which includes cognitive bias . Human factors engineering is often applied to designs in an attempt to minimize this type of error by making systems more forgiving or error-tolerant . (In computational mechanics , when solving
690-604: A system such as Ax = b there is a distinction between the "error" – the inaccuracy in x – and residual – the inaccuracy in Ax .) A notable result of Engineering and Scientific errors that occurred in history is the Chernobyl disaster of 1986, which caused a nuclear meltdown in the City of Chernobyl in present-day Ukraine , and is used as a case study in many Engineering/Science research Numerical analysis provides
736-416: A variety of techniques to represent (store) and compute approximations to mathematical numerical values. Errors arise from a trade-off between efficiency (space and computation time) and precision, which is limited anyway, since (using common floating-point arithmetic ) only a finite amount of values can be represented exactly. The discrepancy between the exact mathematical value and the stored/computed value
782-516: A vignette inverted in relation to its frame, produced without any perforations on one or more sides when the normal stamps are perforated, or printed on the wrong type of paper. Legitimate errors must always be produced and sold unintentionally. Such errors may or may not be scarce or rare. A design error may refer to a mistake in the design of the stamp, such as a mislabeled subject, even if there are no printing or production mistakes. In appellate review , error typically refers to mistakes made by
828-644: Is non-standard (as in vernacular dialects), are considered legitimate speech in scholarly linguistics, but might be considered errors in prescriptivist contexts. See also Error analysis (linguistics) . A gaffe is usually made in a social environment and may come from saying something that may be true but inappropriate. It may also be an erroneous attempt to reveal a truth. Gaffes can be malapropisms , grammatical errors or other verbal and gestural weaknesses or revelations through body language . Actually revealing factual or social truth through words or body language, however, can commonly result in embarrassment or, when
874-428: Is called the approximation error . In applying corrections to the trajectory or course being steered, cybernetics can be seen as the most general approach to error and its correction for the achievement of any goal. The term was suggested by Norbert Wiener to describe a new science of control and information in the animal and the machine. Wiener's early work was on noise . The cybernetician Gordon Pask held that
920-399: Is described as: "Intelligence errors are factual inaccuracies in analysis resulting from poor or missing data; intelligence failure is systemic organizational surprise resulting from incorrect, missing, discarded, or inadequate hypotheses." In numismatics , an error refers to a coin or medal that has a minting mistake, similar to errors found in philately. Because the U.S. Bureau of
966-563: Is often executed inside of the NMI handler routine. Clearing the 7th bit of the PPU's $ 2000 register disables vblank interrupts, and setting it enables them. Error This is an accepted version of this page An error (from the Latin errāre , meaning 'to wander' ) is an inaccurate or incorrect action, thought, or judgement. In statistics , "error" refers to the difference between
SECTION 20
#17327906295901012-439: Is related to considering a scientific hypothesis as true or false, giving birth to two types of errors: Type 1 and Type 2 . The first one is when a true hypothesis is considered false, while the second is the reverse (a false one is considered true). Engineers seek to design devices , machines and systems and in such a way as to mitigate or preferably avoid the effects of error, whether unintentional or not . Such errors in
1058-487: Is said to occur when perfect fidelity is lost in the copying of information . For example, in an asexually reproducing species, an error (or mutation) has occurred for each DNA nucleotide that differs between the child and the parent . Many of these mutations can be harmful, but unlike other types of errors, some are neutral or even beneficial. Mutations are an important force driving evolution . Mutations that make organisms more adapted to their environment increase in
1104-426: Is used as a label for nearly all of the clinical incidents that harm patients. Medical errors are often described as human errors in healthcare. Whether the label is a medical error or human error, one definition used in medicine says that it occurs when a healthcare provider chooses an inappropriate method of care, improperly executes an appropriate method of care, or reads the wrong CT scan . It has been said that
1150-762: The floppy disk controller on the Amstrad PCW , the 8087 coprocessor on the x86 when used in the IBM PC or its compatibles (even though Intel recommended connecting it to a normal interrupt ), and the Low Battery signal on the HP 95LX . In the original IBM PC , an NMI was triggered if a parity error was detected in system memory, or reported by an external device. In either case, the PC would display an error message and halt. Some later IBM-compatibles used an NMI to conceal
1196-480: The Mint keeps a careful eye on all potential errors, errors on U.S. coins are very few and usually very scarce. Examples of numismatic errors: extra metal attached to a coin, a clipped coin caused by the coin stamp machine stamping a second coin too early, double stamping of a coin. A coin that has been overdated, e.g. 1942/41, is also considered an error. In applied linguistics , an error is an unintended deviation from
1242-530: The cartridge port with a wired connector attaching to the monitor port (to generate the interrupt signal when the button was pressed). Far less effective than the earlier Spectrum models and the same as the CPC model, they required the cartridge to be present in order to load saved games. Red, green and blue cartridges have been noted. Anti-Multiface was a public domain program for the Amstrad CPC which allowed
1288-502: The definition should be the subject of more debate. For instance, studies of hand hygiene compliance of physicians in an ICU show that compliance varied from 19% to 85%. The deaths that result from infections caught as a result of treatment providers improperly executing an appropriate method of care by not complying with known safety standards for hand hygiene are difficult to regard as innocent accidents or mistakes. There are many types of medical error, from minor to major, and causality
1334-471: The error that drives a servomechanism can be seen as a difference between a pair of analogous concepts in a servomechanism: the current state and the goal state. Later he suggested error can also be seen as an innovation or a contradiction depending on the context and perspective of interacting (observer) participants. The founder of management cybernetics , Stafford Beer , applied these ideas most notably in his viable system model . In biology , an error
1380-414: The gaffe has negative connotations, friction between people involved. Philosophers and psychologists interested in the nature of the gaffe include Sigmund Freud ( Freudian slip ) and Gilles Deleuze . Deleuze, in his The Logic of Sense , places the gaffe in a developmental process that can culminate in stuttering. Sportswriters and journalists commonly use "gaffe" to refer to any kind of mistake, e.g.
1426-411: The hardware differences from that of the original IBM PC. On such computers, an NMI would be generated when a program attempted to access incompatible hardware. A BIOS interrupt handler would then translate the program's request to match the hardware that was actually present. The SMM in the 386SL is a better way to do this. Some 8-bit home computers used the NMI line to permit a "warm start" if
Multiface - Misplaced Pages Continue
1472-418: The immanent rules of a language variety made by a second language learner. Such errors result from the learner's lack of knowledge of the correct rules of the target language variety. A significant distinction is generally made between errors (systematic deviations) and mistakes ( speech performance errors ) which are not treated the same from a linguistic viewpoint. The study of learners' errors has been
1518-408: The main area of investigation by linguists in the history of second-language acquisition research. A medical error is a preventable adverse effect of care ("iatrogenesis"), whether or not it is evident or harmful to the patient. This might include an inaccurate or incomplete diagnosis or treatment of a disease, injury, syndrome, behavior, infection, or other ailment. The word error in medicine
1564-522: The normal operation of the system. These errors include non-recoverable internal system chipset errors, corruption in system memory such as parity and ECC errors, and data corruption detected on system and peripheral buses. On some systems, a computer user can trigger an NMI through hardware and software debugging interfaces and system reset buttons. Programmers typically use debugging NMIs to diagnose and fix faulty code. In such cases, an NMI can execute an interrupt handler that transfers control to
1610-704: The norms or expectations for behavior or its consequences can be derived from the intention of the actor or from the expectations of other individuals or from a social grouping or from social norms . (See deviance .) Gaffes and faux pas can be labels for certain instances of this kind of error. More serious departures from social norms carry labels such as misbehavior and labels from the legal system, such as misdemeanor and crime . Departures from norms connected to religion can have other labels, such as sin . An individual language user's deviations from standard language norms in grammar , pronunciation and orthography are sometimes referred to as errors . However, in light of
1656-468: The opportunities for cheating that Multiface did. Action Replays for cheating have since been released on newer systems. Other competing systems were a wide array of software-based transfer programs. For game consoles of the 1990s there was the Game Genie , which served a similar purpose in allowing memory values to be edited in order to cheat at games. Non-maskable interrupt In computing ,
1702-405: The population through natural selection as organisms with favorable mutations have more offspring . In philately , an error refers to a postage stamp or piece of postal stationery that exhibits a printing or production mistake that differentiates it from a normal specimen or from the intended result. Examples are stamps printed in the wrong color or missing one or more colors, printed with
1748-463: The restoring of saved memory dumps without the need for a Multiface to be present. It was limited to 128K machines and would not work on dumps bigger than 64K. The program was developed by Serge Querne but credited to "Merlin J. Bond of Magic Software". Competing devices included the Mirage Imager, Disk Wizard, and Action Replay . At the time, none of these could save as many games, or offered
1794-498: The role of language usage in everyday social class distinctions, many feel that linguistics should restrain itself from such prescriptivist judgments to avoid reinforcing dominant class value claims about what linguistic forms should and should not be used. One may distinguish various kinds of linguistic errors – some, such as aphasia or speech disorders , where the user is unable to say what they intend to, are generally considered errors, while cases where natural, intended speech
1840-562: The same price as the Multiface One. The 128 introduced the ability to save to the +D and DISCiPLE disk systems, but lost its joystick port (the Spectrum +2 already had built-in joystick ports). The device was not compatible with the later Spectrum +2A or the Spectrum +3. The Multiface 3, released in November 1987, was designed for the later Amstrad -made models of Spectrum that the 128 did not support. It existed in two versions; one with
1886-626: The system had locked up. Typically, this would restore the control registers to known good values stored in ROM , without destroying whatever data that the user might currently have loaded. On the Commodore 8-bit machines, the RESTORE key was hooked up directly or indirectly to the NMI line on the 6502 -series CPU, but the reset would take place only if the NMI handler routine in ROM detected that RUN/STOP
Multiface - Misplaced Pages Continue
1932-474: The use of an interrupt mask. An NMI is often used when response time is critical or when an interrupt should never be disabled during normal system operation. Such uses include reporting non-recoverable hardware errors, system debugging and profiling, and handling of special cases like system resets. Modern computer architectures typically use NMIs to handle non-recoverable errors which need immediate attention. Therefore, such interrupts should not be masked in
1978-411: The value which has been computed and the correct value. An error could result in failure or in a deviation from the intended performance or behavior. One reference differentiates between "error" and "mistake" as follows: An 'error' is a deviation from accuracy or correctness. A 'mistake' is an error caused by a fault: the fault being misjudgment, carelessness, or forgetfulness. Now, say that I run
2024-559: Was also being held down when RESTORE was struck (this combination being the Commodore version of a three finger salute ). Commodore also connected the MOS Technology 6526 CIA #2 in the C64 and C128 to the processor's NMI line, which was part of the means by which software emulation of the 6551 ACIA was accomplished. Atari 's 8-bit line used a SYSTEM RESET button for this same purpose. Debugging NMIs have appeared in
2070-474: Was at a software level rather than the hardware switch found on the Multiface One. The Multiface 128 was released in April 1987 for the 128K version of the Spectrum, including the original +2 model. It worked in 128K or 48K mode and it existed in two versions; initially without a 'thru-port' and later, with one, both of which originally cost the same £44.95, (equivalent to £160 in 2023) but were later reduced to
2116-439: Was released in 1986 for the ZX Spectrum 48K. It initially cost £39.95 (equivalent to £148 in 2023) and had the capability of saving data to cassette tape , ZX Microdrive , Opus Discovery (an external 3.5 inch disk drive ) or Technology Research Beta (an interface that allowed 5.25 inch and 3.5 inch drives to be connected). The device worked on 128K Spectrums, but only if they were put in 48K mode. It featured
#589410