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56-734: The NeXTdimension ( ND ) is an accelerated 32-bit color board manufactured and sold by NeXT from 1991 that gave the NeXTcube color capabilities with PostScript planned. The NeXTBus ( NuBus -like) card was a full size card for the NeXTcube, filling one of four slots, another one being filled with the main board itself. The NeXTdimension featured S-Video input and output, RGB output, an Intel i860 64-bit RISC processor at 33 MHz for Postscript acceleration, 8 MB main memory (expandable to 64 MB via eight 72-pin SIMM slots) and 4 MB VRAM for

112-482: A 32- bit word length and a memory of 32 words (1 kilobit , 1,024 bits). As it was designed to be the simplest possible stored-program computer, the only arithmetic operations implemented in hardware were subtraction and negation ; other arithmetic operations were implemented in software. The first of three programs written for the machine calculated the highest proper divisor of 2 (262,144), by testing every integer from 2 downwards. This algorithm would take

168-508: A digital computer was ... Where I got this knowledge from I've no idea. Jack Copeland explains that Kilburn's first (pre-Baby) accumulator-free (decentralized, in Jack Good's nomenclature) design was based on inputs from Turing, but that he later switched to an accumulator-based (centralized) machine of the sort advocated by von Neumann, as written up and taught to him by Jack Good and Max Newman. The Baby's seven operation instruction set

224-466: A long time to execute—and so prove the computer's reliability, as division was implemented by repeated subtraction of the divisor. The program consisted of 17 instructions and ran for about 52 minutes before reaching the correct answer of 131,072, after the Baby had performed about 3.5 million operations (for an effective CPU speed of about 1100 instructions per second ). The first design for

280-477: A mirror surface. HDR imagery allows for the reflection of highlights that can still be seen as bright white areas, instead of dull grey shapes. A 32-bit file format is a binary file format for which each elementary information is defined on 32 bits (or 4 bytes ). An example of such a format is the Enhanced Metafile Format . Manchester Baby The Manchester Baby , also called

336-679: A positive charge 1. The charge dissipated in about 0.2 seconds, but it could be automatically refreshed from the data picked up by the detector. The Williams tube used in Baby was based on the CV1131, a commercially available 12-inch (300 mm) diameter CRT, but a smaller 6-inch (150 mm) tube, the CV1097, was used in the Mark I. After developing the Colossus computer for code breaking at Bletchley Park during World War II, Max Newman

392-472: A power consumption of 3500 watts. The arithmetic unit was built using EF50 pentode valves, which had been widely used during wartime. The Baby used one Williams tube to provide 32 by 32-bit words of random-access memory (RAM), a second to hold a 32-bit accumulator in which the intermediate results of a calculation could be stored temporarily, and a third to hold the current program instruction along with its address in memory. A fourth CRT, without

448-405: A program-controlled computer was Charles Babbage 's Analytical Engine in the 1830s, with Ada Lovelace conceiving the idea of the first theoretical program to calculate Bernoulli numbers . A century later, in 1936, mathematician Alan Turing published his description of what became known as a Turing machine , a theoretical concept intended to explore the limits of mechanical computation. Turing

504-469: A resolution of 1120x832 at 24-bit color plus 8-bit alpha channel. An onboard C-Cube CL550 chip for MJPEG video compression featured in the announced specification, but this was omitted from the delivered product. An estimated three-month delay in delivering the CL550 caused NeXT to redesign the product to accept a daughterboard providing image compression functionality. A handful of engineering prototypes for

560-536: A set of 32 buttons and switches known as the input device to set the value of each bit of each word to either 0 or 1. The Baby had no paper-tape reader or punch . Three programs were written for the computer. The first, consisting of 17 instructions, was written by Kilburn, and so far as can be ascertained first ran on 21 June 1948. It was designed to find the highest proper factor of 2 (262,144) by trying every integer from 2  − 1 downwards. The divisions were implemented by repeated subtractions of

616-413: A total of 96 bits per pixel. 32-bit-per-channel images are used to represent values brighter than what sRGB color space allows (brighter than white); these values can then be used to more accurately retain bright highlights when either lowering the exposure of the image or when it is seen through a dark filter or dull reflection. For example, a reflection in an oil slick is only a fraction of that seen in

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672-429: A word from memory, giving an instruction execution rate of about 700 per second. The main store was refreshed continuously, a process that took 20 milliseconds to complete, as each of the Baby's 32 words had to be read and then refreshed in sequence. The Baby represented negative numbers using two's complement , as most computers still do. In that representation, the value of the most significant bit denotes

728-402: Is a 32-bit machine, with 32-bit registers and instructions that manipulate 32-bit quantities, but the external address bus is 36 bits wide, giving a larger address space than 4 GB, and the external data bus is 64 bits wide, primarily in order to permit a more efficient prefetch of instructions and data. Prominent 32-bit instruction set architectures used in general-purpose computing include

784-606: The 8088/8086 or 80286 , 16-bit microprocessors with a segmented address space where programs had to switch between segments to reach more than 64 kilobytes of code or data. As this is quite time-consuming in comparison to other machine operations, the performance may suffer. Furthermore, programming with segments tend to become complicated; special far and near keywords or memory models had to be used (with care), not only in assembly language but also in high level languages such as Pascal , compiled BASIC , Fortran , C , etc. The 80386 and its successors fully support

840-824: The IBM System/360 , IBM System/370 (which had 24-bit addressing), System/370-XA , ESA/370 , and ESA/390 (which had 31-bit addressing), the DEC VAX , the NS320xx , the Motorola 68000 family (the first two models of which had 24-bit addressing), the Intel IA-32 32-bit version of the x86 architecture, and the 32-bit versions of the ARM , SPARC , MIPS , PowerPC and PA-RISC architectures. 32-bit instruction set architectures used for embedded computing include

896-551: The IBM System/360 Model 30 had an 8-bit ALU, 8-bit internal data paths, and an 8-bit path to memory, and the original Motorola 68000 had a 16-bit data ALU and a 16-bit external data bus, but had 32-bit registers and a 32-bit oriented instruction set. The 68000 design was sometimes referred to as 16/32-bit . However, the opposite is often true for newer 32-bit designs. For example, the Pentium Pro processor

952-596: The Ministry of Supply had concluded that Britain needed a National Mathematical Laboratory to co-ordinate machine-aided computation. A Mathematics Division was set up at the NPL, and on 19 February 1946 Turing presented a paper outlining his design for an electronic stored-program computer to be known as the Automatic Computing Engine (ACE). This was one of several projects set up in the years following

1008-691: The Small-Scale Experimental Machine ( SSEM ), was the first electronic stored-program computer . It was built at the University of Manchester by Frederic C. Williams , Tom Kilburn , and Geoff Tootill , and ran its first program on 21 June 1948. The Baby was not intended to be a practical computing engine, but was instead designed as a testbed for the Williams tube , the first truly random-access memory . Described as "small and primitive" 50 years after its creation, it

1064-475: The Williams tube or Williams–Kilburn tube, based on a standard CRT: the first electronic random-access digital storage device. The Baby was designed to show that it was a practical storage device by demonstrating that data held within it could be read and written reliably at a speed suitable for use in a computer. For use in a binary digital computer, the tube had to be capable of storing either one of two states at each of its memory locations, corresponding to

1120-448: The integer representation used. With the two most common representations, the range is 0 through 4,294,967,295 (2 − 1) for representation as an ( unsigned ) binary number , and −2,147,483,648 (−2 ) through 2,147,483,647 (2 − 1) for representation as two's complement . One important consequence is that a processor with 32-bit memory addresses can directly access at most 4  GiB of byte-addressable memory (though in practice

1176-550: The "circuit man" for a new computer project for which he had secured funding from the Royal Society . Having secured the support of the university, obtained funding from the Royal Society, and assembled a first-rate team of mathematicians and engineers, Newman now had all elements of his computer-building plan in place. Adopting the approach he had used so effectively at Bletchley Park, Newman set his people loose on

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1232-533: The 16-bit segments of the 80286 but also segments for 32-bit address offsets (using the new 32-bit width of the main registers). If the base address of all 32-bit segments is set to 0, and segment registers are not used explicitly, the segmentation can be forgotten and the processor appears as having a simple linear 32-bit address space. Operating systems like Windows or OS/2 provide the possibility to run 16-bit (segmented) programs as well as 32-bit programs. The former possibility exists for backward compatibility and

1288-423: The 68000 family and ColdFire , x86, ARM, MIPS, PowerPC, and Infineon TriCore architectures. On the x86 architecture , a 32-bit application normally means software that typically (not necessarily) uses the 32-bit linear address space (or flat memory model ) possible with the 80386 and later chips. In this context, the term came about because DOS , Microsoft Windows and OS/2 were originally written for

1344-568: The MJPEG daughterboard exist. A stripped down Mach kernel was used as the operating system for the card. Due to the supporting processor, 32-bit color on the NeXTdimension was faster than 2-bit greyscale Display PostScript on the NeXTcube. Display PostScript never actually ran on the board so the Intel i860 never did much more than move blocks of color data around. The Motorola 68040 did

1400-485: The NPL decided that, of all the work being carried out by the TRE on its behalf, ACE was to be given the top priority. NPL's decision led to a visit by the superintendent of the TRE's Physics Division on 22 November 1946, accompanied by Frederic C. Williams and A. M. Uttley, also from the TRE. Williams led a TRE development group working on CRT stores for radar applications, as an alternative to delay lines. Williams

1456-611: The Second World War with the aim of constructing a stored-program computer. At about the same time, EDVAC was under development at the University of Pennsylvania 's Moore School of Electrical Engineering , and the University of Cambridge Mathematical Laboratory was working on EDSAC . The NPL did not have the expertise to build a machine like ACE, so they contacted Tommy Flowers at the General Post Office 's (GPO) Dollis Hill Research Laboratory . Flowers,

1512-442: The TRE. Although some early computers such as EDSAC, inspired by the design of EDVAC, later made successful use of mercury delay-line memory , the technology had several drawbacks: it was heavy, it was expensive, and it did not allow data to be accessed randomly. In addition, because data was stored as a sequence of acoustic waves propagated through a mercury column, the device's temperature had to be very carefully controlled, as

1568-452: The binary digits ( bits ) 0 and 1. It exploited the positive or negative electric charge generated by displaying either a dash or a dot at any position on the CRT screen, a phenomenon known as secondary emission . A dash generated a positive charge, and a dot a negative charge, either of which could be picked up by a detector plate in front of the screen; a negative charge represented 0, and

1624-648: The conditional branching of a Turing machine. On 12 May 1941, the Z3 was successfully presented to an audience of scientists of the Deutsche Versuchsanstalt für Luftfahrt ("German Laboratory for Aviation") in Berlin . The Z3 stored its program on an external tape, but it was electromechanical rather than electronic. The earliest electronic computing devices were the Atanasoff–Berry computer (ABC), which

1680-701: The construction of a more practical computer, the Manchester Mark 1 , work on which began in August 1948. The first version was operational by April 1949, and it in turn led directly to the development of the Ferranti Mark 1 , the world's first commercially available general-purpose computer. In 1998, a working replica of the Baby, now on display at the Museum of Science and Industry in Manchester ,

1736-550: The crunching and the board, while fast for its time, never lived up to the hype. Since the main board always included the greyscale video logic, each NeXTdimension allowed the simultaneous use of an additional monitor. List price for a NeXTdimension sold as an add-on to the NeXTcube was US$ 3,995 (equivalent to $ 8,940 in 2023), and US$ 2,995 (equivalent to $ 6,700 in 2023) for the MegaPixel Color Display. 32-bit 32-bit designs have been used since

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1792-482: The designer of Colossus, the world's first programmable electronic computer, was committed elsewhere and was unable to take part in the project, although his team did build some mercury delay lines for ACE. The Telecommunications Research Establishment (TRE) was also approached for assistance, as was Maurice Wilkes at the University of Cambridge Mathematical Laboratory. The government department responsible for

1848-582: The detailed work while he concentrated on orchestrating the endeavor. Following his appointment to the Chair of Electrical Engineering at Manchester University, Williams recruited his TRE colleague Tom Kilburn on secondment. By the autumn of 1947 the pair had increased the storage capacity of the Williams tube from one bit to 2,048, arranged in a 64 by 32-bit array, and demonstrated that it was able to store those bits for four hours. Engineer Geoff Tootill joined

1904-542: The divisor. The Baby took 3.5 million operations and 52 minutes to produce the answer (131,072). The program used eight words of working storage in addition to its 17 words of instructions, giving a program size of 25 words. Geoff Tootill wrote an amended version of the program the following month, and in mid-July Alan Turing — who had been appointed as a reader in the mathematics department at Manchester University in September 1948 — submitted

1960-490: The earliest days of electronic computing, in experimental systems and then in large mainframe and minicomputer systems. The first hybrid 16/32-bit microprocessor , the Motorola 68000 , was introduced in the late 1970s and used in systems such as the original Apple Macintosh . Fully 32-bit microprocessors such as the HP FOCUS , Motorola 68020 and Intel 80386 were launched in the early to mid 1980s and became dominant by

2016-722: The early 1990s. This generation of personal computers coincided with and enabled the first mass-adoption of the World Wide Web . While 32-bit architectures are still widely-used in specific applications, the PC and server market has moved on to 64 bits with x86-64 and other 64-bit architectures since the mid-2000s with installed memory often exceeding the 32-bit 4G RAM address limits on entry level computers. The latest generation of smartphones have also switched to 64 bits. A 32-bit register can store 2 different values. The range of integer values that can be stored in 32 bits depends on

2072-574: The first decades of 32-bit architectures (the 1960s to the 1980s). Older 32-bit processor families (or simpler, cheaper variants thereof) could therefore have many compromises and limitations in order to cut costs. This could be a 16-bit ALU , for instance, or external (or internal) buses narrower than 32 bits, limiting memory size or demanding more cycles for instruction fetch, execution or write back. Despite this, such processors could be labeled 32-bit , since they still had 32-bit registers and instructions able to manipulate 32-bit quantities. For example,

2128-440: The idea of using the computer's memory to hold the program as well as the data it was working on, and it was mathematician John von Neumann who wrote a widely distributed paper describing that computer architecture, still used in almost all computers. The construction of a von Neumann computer depended on the availability of a suitable memory device on which to store the program. During the Second World War researchers working on

2184-412: The latter is usually meant to be used for new software development . In digital images/pictures, 32-bit usually refers to RGBA color space ; that is, 24-bit truecolor images with an additional 8-bit alpha channel . Other image formats also specify 32 bits per pixel, such as RGBE . In digital images, 32-bit sometimes refers to high-dynamic-range imaging (HDR) formats that use 32 bits per channel,

2240-468: The limit may be lower). The world's first stored-program electronic computer , the Manchester Baby , used a 32-bit architecture in 1948, although it was only a proof of concept and had little practical capacity. It held only 32 32-bit words of RAM on a Williams tube , and had no addition operation, only subtraction. Memory, as well as other digital circuits and wiring, was expensive during

2296-688: The machine's storage was described with the least significant digits to the left; thus a one was represented in three bits as "100", rather than the more conventional "001". The awkward negative operations were a consequence of the Baby's lack of hardware to perform any arithmetic operations except subtraction and negation . It was considered unnecessary to build an adder before testing could begin as addition can easily be implemented by subtraction, i.e. x + y can be computed as −(− x − y ). Therefore, adding two numbers together, X and Y, required four instructions: Programs were entered in binary form by stepping through each word of memory in turn, and using

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2352-492: The problem of removing the clutter from radar signals had developed a form of delay-line memory , the first practical application of which was the mercury delay line, developed by J. Presper Eckert . Radar transmitters send out regular brief pulses of radio energy, the reflections from which are displayed on a CRT screen. As operators are usually interested only in moving targets, it was desirable to filter out any distracting reflections from stationary objects. The filtering

2408-436: The remaining 16 bits were unused. The Baby's single operand architecture meant that the second operand of any operation was implicit: the accumulator or the program counter (instruction address); program instructions specified only the address of the data in memory. A word in the computer's memory could be read, written, or refreshed, in 360 microseconds. An instruction took four times as long to execute as accessing

2464-407: The sign of a number; positive numbers have a zero in that position and negative numbers a one. Thus, the range of numbers that could be held in each 32-bit word was −2 to +2  − 1 (decimal: −2,147,483,648 to +2,147,483,647). The Baby's instruction format had a three-bit operation code field, which allowed a maximum of eight (2 ) different instructions. In contrast to the modern convention,

2520-404: The storage electronics of the other three, was used as the output device, able to display the bit pattern of any selected storage tube. Each 32-bit word of RAM could contain either a program instruction or data. In a program instruction, bits 0–12 represented the memory address of the operand to be used, and bits 13–15 specified the operation to be executed, such as storing a number in memory;

2576-444: The team on loan from TRE in September 1947, and remained on secondment until April 1949. Now let's be clear before we go any further that neither Tom Kilburn nor I knew the first thing about computers when we arrived at Manchester University ... Newman explained the whole business of how a computer works to us." Kilburn had a hard time recalling the influences on his machine design: [I]n that period, somehow or other I knew what

2632-563: The third program, to carry out long division . Turing had by then been appointed to the nominal post of Deputy Director of the Computing Machine Laboratory at the university, although the laboratory did not become a physical reality until 1951. Williams and Kilburn reported on the Baby in a letter to the Journal Nature , published in September 1948. The machine's successful demonstration quickly led to

2688-482: The velocity of sound through a medium varies with its temperature. Williams had seen an experiment at Bell Labs demonstrating the effectiveness of cathode-ray tubes (CRT) as an alternative to the delay line for removing ground echoes from radar signals. While working at the TRE, shortly before he joined the University of Manchester in December 1946, he and Tom Kilburn had developed a form of electronic memory known as

2744-578: Was achieved by comparing each received pulse with the previous pulse, and rejecting both if they were identical, leaving a signal containing only the images of any moving objects. To store each received pulse for later comparison it was passed through a transmission line, delaying it by exactly the time between transmitted pulses. Turing joined the National Physical Laboratory (NPL) in October 1945, by which time scientists within

2800-439: Was approximately a subset of the twelve operation instruction set proposed in 1947 by Jack Good, in the first known document to use the term "Baby" for this machine. Good did not include a "halt" instruction, and his proposed conditional jump instruction was more complicated than what the Baby implemented. Although Newman played no engineering role in the development of the Baby, or any of the subsequent Manchester computers , he

2856-474: Was committed to the development of a computer incorporating both Alan Turing 's mathematical concepts and the stored-program concept that had been described by John von Neumann . In 1945, he was appointed to the Fielden Chair of Pure Mathematics at Manchester University; he took his Colossus-project colleagues Jack Good and David Rees to Manchester with him, and there they recruited F. C. Williams to be

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2912-629: Was generally supportive and enthusiastic about the project, and arranged for the acquisition of war-surplus supplies for its construction, including GPO metal racks and "…the material of two complete Colossi" from Bletchley. Racks and Colossi parts were modified and assembled into chassis by Norman Stanley Hammond and others. By June 1948 the Baby had been built and was working. It was 17 feet (5.2 m) in length, 7 feet 4 inches (2.24 m) tall, and weighed almost 1 long ton (1.0 t). The machine contained 550  valves (vacuum tubes) —300  diodes and 250  pentodes —and had

2968-507: Was not available to work on the ACE because he had already accepted a professorship at the University of Manchester , and most of his circuit technicians were in the process of being transferred to the Department of Atomic Energy. The TRE agreed to second a small number of technicians to work under Williams' direction at the university, and to support another small group working with Uttley at

3024-507: Was not imagining a physical machine, but a person he called a "computer", who acted according to the instructions provided by a tape on which symbols could be read and written sequentially as the tape moved under a tape head. Turing proved that if an algorithm can be written to solve a mathematical problem, then a Turing machine can execute that algorithm. Konrad Zuse 's Z3 was the world's first working programmable , fully automatic computer, with binary digital arithmetic logic, but it lacked

3080-510: Was successfully tested in 1942, and the Colossus of 1943, but neither was a stored-program machine. The ENIAC (1946) was the first automatic computer that was both electronic and general-purpose. It was Turing complete , with conditional branching, and programmable to solve a wide range of problems, but its program was held in the state of switches in patch cords, rather than machine-changeable memory, and it could take several days to reprogram. Researchers such as Turing and Zuse investigated

3136-458: Was the first working machine to contain all the elements essential to a modern electronic digital computer. As soon as the Baby had demonstrated the feasibility of its design, a project was initiated at the university to develop it into a full-scale operational machine, the Manchester Mark 1 . The Mark 1 in turn quickly became the prototype for the Ferranti Mark 1 , the world's first commercially available general-purpose computer. The Baby had

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