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42-416: ARM11 is a group of 32-bit RISC ARM processor cores licensed by ARM Holdings . The ARM11 core family consists of ARM1136J(F)-S, ARM1156T2(F)-S, ARM1176JZ(F)-S, and ARM11MPCore. Since ARM11 cores were released from 2002 to 2005 , they are no longer recommended for new IC designs, instead ARM Cortex-A and ARM Cortex-R cores are preferred. The ARM11 product family (announced 29 April 2002) introduced

84-615: A nibble ), usually with additional bits for a sign. Many modern CPUs provide limited support for decimal integers as an extended datatype, providing instructions for converting such values to and from binary values. Depending on the architecture, decimal integers may have fixed sizes (e.g., 7 decimal digits plus a sign fit into a 32-bit word), or may be variable-length (up to some maximum digit size), typically occupying two digits per byte (octet). IPv6 addresses, GUIDs Different CPUs support different integral data types. Typically, hardware will support both signed and unsigned types, but only

126-597: A binary computing system. The most common is two's complement , which allows a signed integral type with n bits to represent numbers from −2 through 2 − 1 . Two's complement arithmetic is convenient because there is a perfect one-to-one correspondence between representations and values (in particular, no separate +0 and −0 ), and because addition , subtraction and multiplication do not need to distinguish between signed and unsigned types. Other possibilities include offset binary , sign-magnitude , and ones' complement . Some computer languages define integer sizes in

168-663: A machine-independent way; others have varying definitions depending on the underlying processor word size. Not all language implementations define variables of all integer sizes, and defined sizes may not even be distinct in a particular implementation. An integer in one programming language may be a different size in a different language, on a different processor, or in an execution context of different bitness; see § Words . Some older computer architectures used decimal representations of integers, stored in binary-coded decimal (BCD) or other format. These values generally require data sizes of 4 bits per decimal digit (sometimes called

210-498: 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 . Integer (computer science)#Value and representation In computer science, an integer

252-638: A positive integer is a string of bits , using the binary numeral system . The order of the memory bytes storing the bits varies; see endianness . The width , precision , or bitness of an integral type is the number of bits in its representation. An integral type with n bits can encode 2 numbers; for example an unsigned type typically represents the non-negative values 0 through 2 − 1 . Other encodings of integer values to bit patterns are sometimes used, for example binary-coded decimal or Gray code , or as printed character codes such as ASCII . There are four well-known ways to represent signed numbers in

294-523: A programmer using the C language incorrectly declares as int a variable that will be used to store values greater than 2 −1, the program will fail on computers with 16-bit integers. That variable should have been declared as long , which has at least 32 bits on any computer. Programmers may also incorrectly assume that a pointer can be converted to an integer without loss of information, which may work on (some) 32-bit computers, but fail on 64-bit computers with 64-bit pointers and 32-bit integers. This issue

336-462: A sequence of digits optionally prefixed with + or −. Some programming languages allow other notations, such as hexadecimal (base 16) or octal (base 8). Some programming languages also permit digit group separators . The internal representation of this datum is the way the value is stored in the computer's memory. Unlike mathematical integers, a typical datum in a computer has some minimal and maximum possible value. The most common representation of

378-436: A single bit, but is often given a full byte for convenience of addressing and speed of access. A four-bit quantity is known as a nibble (when eating, being smaller than a bite ) or nybble (being a pun on the form of the word byte ). One nibble corresponds to one digit in hexadecimal and holds one digit or a sign code in binary-coded decimal. The term byte initially meant 'the smallest addressable unit of memory'. In

420-416: A small, fixed set of widths. The table above lists integral type widths that are supported in hardware by common processors. High-level programming languages provide more possibilities. It is common to have a 'double width' integral type that has twice as many bits as the biggest hardware-supported type. Many languages also have bit-field types (a specified number of bits, usually constrained to be less than

462-413: 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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504-404: A way to represent a processor register or memory address as an integer. The value of an item with an integral type is the mathematical integer that it corresponds to. Integral types may be unsigned (capable of representing only non-negative integers) or signed (capable of representing negative integers as well). An integer value is typically specified in the source code of a program as

546-452: A whole integer whose range is greater than or equal to that of a standard integer on the same machine. In C , it is denoted by long . It is required to be at least 32 bits, and may or may not be larger than a standard integer. A conforming program can assume that it can safely store values between −(2 −1) and 2 −1, but it may not assume that the range is not larger. In the C99 version of

588-422: A word is thus CPU-specific. Many different word sizes have been used, including 6-, 8-, 12-, 16-, 18-, 24-, 32-, 36-, 39-, 40-, 48-, 60-, and 64-bit. Since it is architectural, the size of a word is usually set by the first CPU in a family, rather than the characteristics of a later compatible CPU. The meanings of terms derived from word , such as longword , doubleword , quadword , and halfword , also vary with

630-454: Is a datum of integral data type , a data type that represents some range of mathematical integers . Integral data types may be of different sizes and may or may not be allowed to contain negative values. Integers are commonly represented in a computer as a group of binary digits (bits). The size of the grouping varies so the set of integer sizes available varies between different types of computers. Computer hardware nearly always provides

672-402: 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

714-420: Is magnified many times. The ARM11 generation focused more on synthesis than previous generations, making such concerns more of an issue. There are four ARM11 cores: BlackBerry Torch 9810 32-bit 32-bit designs have been used since the earliest days of electronic computing, in experimental systems and then in large mainframe and minicomputer systems. The first hybrid 16/32-bit microprocessor ,

756-453: Is often smaller than a standard integer, but this is not required. A conforming program can assume that it can safely store values between −(2 −1) and 2 −1, but it may not assume that the range is not larger. In Java , a short is always a 16-bit integer. In the Windows API , the datatype SHORT is defined as a 16-bit signed integer on all machines. A long integer can represent

798-472: Is permitted. This can be an issue when exchanging code and data between platforms, or doing direct hardware access. Thus, there are several sets of headers providing platform independent exact width types. The C standard library provides stdint.h ; this was introduced in C99 and C++11. Integer literals can be written as regular Arabic numerals , consisting of a sequence of digits and with negation indicated by

840-423: Is platform-dependent. In C , it is denoted by int and required to be at least 16 bits. Windows and Unix systems have 32-bit int s on both 32-bit and 64-bit architectures. A short integer can represent a whole number that may take less storage, while having a smaller range, compared with a standard integer on the same machine. In C , it is denoted by short . It is required to be at least 16 bits, and

882-491: Is resolved by C99 in stdint.h in the form of intptr_t . The bitness of a program may refer to the word size (or bitness) of the processor on which it runs, or it may refer to the width of a memory address or pointer, which can differ between execution modes or contexts. For example, 64-bit versions of Microsoft Windows support existing 32-bit binaries, and programs compiled for Linux's x32 ABI run in 64-bit mode yet use 32-bit memory addresses. The standard integer size

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924-606: 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

966-547: The ARMv6 architectural additions which had been announced in October 2001. These include SIMD media instructions, multiprocessor support, exclusive loads and stores instructions and a new cache architecture. The implementation included a significantly improved instruction processing pipeline, compared to previous ARM9 or ARM10 families, and is used in smartphones from Apple , Nokia , and others. The initial ARM11 core (ARM1136)

1008-632: The C programming language and the C++11 version of C++ , a long long type is supported that has double the minimum capacity of the standard long . This type is not supported by compilers that require C code to be compliant with the previous C++ standard, C++03, because the long long type did not exist in C++03. For an ANSI/ISO compliant compiler, the minimum requirements for the specified ranges, that is, −(2 −1) to 2 −1 for signed and 0 to 2 −1 for unsigned, must be fulfilled; however, extending this range

1050-793: 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

1092-536: 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

1134-578: 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 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,

1176-448: 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

1218-533: 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

1260-423: 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

1302-462: The CPU and OS. Practically all new desktop processors are capable of using 64-bit words, though embedded processors with 8- and 16-bit word size are still common. The 36-bit word length was common in the early days of computers. One important cause of non-portability of software is the incorrect assumption that all computers have the same word size as the computer used by the programmer. For example, if

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1344-449: 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

1386-402: The chip design flow, which included extensive use of formal verification techniques. Without such attention, integrating an ARM11 with third-party designs could risk exposing hard-to-find latent bugs. Due to ARM cores being integrated into many different designs, using a variety of logic synthesis tools and chip manufacturing processes, the impact of its register-transfer level (RTL) quality

1428-517: The computer's memory as is necessary to store the numbers; however, a computer has only a finite amount of storage, so they, too, can only represent a finite subset of the mathematical integers. These schemes support very large numbers; for example one kilobyte of memory could be used to store numbers up to 2466 decimal digits long. A Boolean or Flag type is a type that can represent only two values: 0 and 1, usually identified with false and true respectively. This type can be stored in memory using

1470-407: The field of computer networking , where computers with different byte widths might have to communicate. In modern usage byte almost invariably means eight bits, since all other sizes have fallen into disuse; thus byte has come to be synonymous with octet . The term 'word' is used for a small group of bits that are handled simultaneously by processors of a particular architecture . The size of

1512-574: 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,

1554-412: 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,

1596-461: 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

1638-567: The maximum hardware-supported width) and range types (that can represent only the integers in a specified range). Some languages, such as Lisp , Smalltalk , REXX , Haskell , Python , and Raku , support arbitrary precision integers (also known as infinite precision integers or bignums ). Other languages that do not support this concept as a top-level construct may have libraries available to represent very large numbers using arrays of smaller variables, such as Java's BigInteger class or Perl 's " bigint " package. These use as much of

1680-407: The past, 5-, 6-, 7-, 8-, and 9-bit bytes have all been used. There have also been computers that could address individual bits ('bit-addressed machine'), or that could only address 16- or 32-bit quantities ('word-addressed machine'). The term byte was usually not used at all in connection with bit- and word-addressed machines. The term octet always refers to an 8-bit quantity. It is mostly used in

1722-704: Was released to licensees in October 2002. The ARM11 family are currently the only ARMv6-architecture cores. There are, however, ARMv6-M cores ( Cortex-M0 and Cortex-M1 ), addressing microcontroller applications; ARM11 cores target more demanding applications. In terms of instruction set, ARM11 builds on the preceding ARM9 generation. It incorporates all ARM926EJ-S features and adds the ARMv6 instructions for media support (SIMD) and accelerating IRQ response. Microarchitecture improvements in ARM11 cores include: JTAG debug support (for halting, stepping, breakpoints, and watchpoints)

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1764-597: Was simplified. The EmbeddedICE module was replaced with an interface which became part of the ARMv7 architecture. The hardware tracing modules (ETM and ETB) are compatible, but updated, versions of those used in the ARM9. In particular, trace semantics were updated to address parallel instruction execution and data transfers. ARM makes an effort to promote recommended Verilog coding styles and techniques. This ensures semantically rigorous designs, preserving identical semantics throughout

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