English Electric KDF9KDF9 was an early British 48-bit computer designed and built by English Electric (which in 1968 was merged into International Computers Limited (ICL)). The first machine came into service in 1964 and the last two of the 29 machines were decommissioned in 1980 at the National Physical Laboratory. The KDF9 was designed for, and used almost entirely in, the mathematical and scientific processing fields – in 1967, nine were in use in UK universities and technical colleges.
OctalBase-8 numeral representation Numeral systems, bits and Gray code hex dec oct 3 2 1 0 step 0hex 00dec 00oct 0 0 0 0 g0 1hex 01dec 01oct 0 0 0 1 h1 2hex 02dec 02oct 0 0 1 0 j3 3hex 03dec 03oct 0 0 1 1 i2 4hex 04dec 04oct 0 1 0 0 n7 5hex 05dec 05oct 0 1 0 1 m6 6hex 06dec 06oct 0 1 1 0 k4 7hex 07dec 07oct 0 1 1 1 l5 8hex 08dec 10oct 1 0 0 0 vF 9hex 09dec 11oct 1 0 0 1 uE Ahex 10dec 12oct 1 0 1 0 sC Bhex 11dec 13oct 1 0 1 1 tD Chex 12dec 14oct 1 1 0 0 o8 Dhex 13dec 15oct 1 1 0 1 p9 Ehex 14dec 16oct 1 1 1 0 rB Fhex 15dec 17oct 1 1 1 1 qA Part of a series onNumeral systems Place-value notation Hindu–Arabic numerals Western Arabic Eastern Arabic Bengali Devanagari Gujarati Gurmukhi Odia Sinhala Tamil Malayalam Telugu Kannada Dzongkha Tibetan Balinese Burmese Javanese Khmer Lao Mongolian Sundanese Thai Other systems History Ancient Babylonian Post-classical Cistercian Mayan Muisca Pentadic Quipu Rumi Contemporary Cherokee Kaktovik (Iñupiaq) By radix/base Common radices/bases 2 3 4 5 6 8 10 11 12 16 20 60 Non-standard radices/bases Bijective (1) Signed-digit (balanced ternary) Mixed (factorial) Negative Complex (2i) Non-integer (φ) Asymmetric Sign-value notation Non-alphabetic Contemporary East Asian Chinese Hokkien Suzhou Japanese Korean Vietnamese Historic East Asian Counting rods Tangut Other non-alphabetic Aegean Attic Aztec Brahmi Chuvash Egyptian Etruscan Kharosthi Prehistoric counting Proto-cuneiform Roman Tally marks Alphabetic Abjad Armenian Alphasyllabic Akṣarapallī Āryabhaṭa Kaṭapayādi Coptic Cyrillic Geʽez Georgian Glagolitic Greek Hebrew List of numeral systemsvte Octal is a numeral system for representing a numeric value as base 8.English ElectricThe English Electric Company Limited (EE) was a British industrial manufacturer formed after World War I by amalgamating five businesses which, during the war, made munitions, armaments and aeroplanes. It initially specialised in industrial electric motors and transformers, locomotives and traction equipment, diesel motors and steam turbines.
ByteThe byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures. To disambiguate arbitrarily sized bytes from the common 8-bit definition, network protocol documents such as the Internet Protocol (RFC791) refer to an 8-bit byte as an octet.
BitThe bit is the most basic unit of information in computing and digital communication. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represented as 1 and 0, but other representations such as true/false, yes/no, on/off, and +/− are also widely used.
Machine codeIn computing, machine code is dataencoded and structured to control a computer's central processing unit (CPU) via its programmable interface. A computer program consists primarily of sequences of machine-code instructions. Machine code is classified as native with respect to its host CPU since it is the language that the CPU interprets directly.
Syllable (computing)In computing, a syllable is a unit of information that describes the size of data for some digital hardware from the 1960s and 1970s. The size of the unit varies by hardware design in much the same way that word does. The term is not used for modern hardware; standardized terms, such as byte, are used instead.HDOSHDOS is a microcomputer disk operating system, originally written for the 1977 Heathkit H8 computer system and later also available for the Heathkit H89 and Zenith Z-89 computers. The author was Heath Company employee Gordon Letwin, who later was an early employee of Microsoft and lead architect of OS/2.
IBM 7030 StretchThe IBM 7030, also known as Stretch, was IBM's first transistorizedsupercomputer. It was the fastest computer in the world from 1961 until the first CDC 6600 became operational in 1964. Originally designed to meet a requirement formulated by Edward Teller at Lawrence Livermore National Laboratory, the first example was delivered to Los Alamos National Laboratory in 1961, and a second customized version, the IBM 7950 Harvest, to the National Security Agency in 1962.
HeathkitHeathkit is the brand name of kits and other electronic products produced and marketed by the Heath Company.
Numeral systemNotation for expressing numbers Numbers written in different numeral systems A numeral system is a writing system for expressing numbers without words; that is, a mathematical notation for representing numbers of a given set, using digits (in positional notation) or other symbols (in sign-value notation) in a consistent manner. The same sequence of symbols may represent different numbers in different numeral systems.*As an Amazon Associate I earn from qualifying purchases.