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Johnson Counter
A ring counter is a type of counter composed of flip-flops connected into a shift register, with the output of the last flip-flop fed to the input of the first, making a "circular" or "ring" structure. There are two types of ring counters: * A straight ring counter, also known as a one-hot counter, connects the output of the last shift register to the first shift register input and circulates a single one (or zero) bit around the ring. * A twisted ring counter, also called switch-tail ring counter, walking ring counter, Johnson counter, or Möbius counter, connects the complement of the output of the last shift register to the input of the first register and circulates a stream of ones followed by zeros around the ring. Four-bit ring-counter sequences Properties Ring counters are often used in hardware design (e.g. ASIC and FPGA design) to create finite-state machines. A binary counter would require an adder circuit which is substantially more complex than a ring coun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flip-flop (electronics)
In electronics, flip-flops and latches are electronic circuit, circuits that have two stable states that can store state information – a bistable multivibrator. The circuit can be made to change state by signals applied to one or more control inputs and will output its state (often along with its logical complement too). It is the basic storage element in sequential logic. Flip-flops and latches are fundamental building blocks of digital electronics systems used in computers, communications, and many other types of systems. Flip-flops and latches are used as data storage elements to store a single ''bit'' (binary digit) of data; one of its two states represents a "one" and the other represents a "zero". Such data storage can be used for storage of ''state (computer science), state'', and such a circuit is described as sequential logic in electronics. When used in a finite-state machine, the output and next state depend not only on its current input, but also on its current stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilcox P
Wilcox may refer to: Places ;Canada *Wilcox, Saskatchewan ;United States *Wilcox, Florida, an unincorporated community in Gilchrist County, Florida *Wilcox, Missouri, an unincorporated community in Nodaway County, Missouri *Wilcox, Nebraska *Wilcox, Pennsylvania *Wilcox, Washington *Wilcox, Wisconsin *Wilcox County, Alabama *Wilcox County, Georgia *Wilcox Township, Michigan *Wilcox, Burleson County, Texas *Wilcox, Somervell County, Texas *Wilcox, Wyoming People *Wilcox (surname) Other *Wilcox Formation, a Paleogene age geologic formation in the Gulf of Mexico *Wilcox (film), ''Wilcox'' (film), a 2019 Canadian drama film *Wilcox, Crittenden Mill, a property in Middletown, Connecticut *Adrian C. Wilcox High School, Santa Clara, California, USA *Babcock & Wilcox, American manufacturer of power generation equipment *George Wilcox & Co, a South Australian hide and wool business, which became Wilcox Mofflin Ltd. *Wilcox Group, Canadian crisis management company *Wilcox Health, Hospital a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual-tone Multi-frequency Signaling
Dual-tone multi-frequency (DTMF) signaling is a telecommunication signaling system using the voice-frequency band over telephone lines between telephone equipment and other communications devices and Automatic telephone exchange, switching centers. DTMF was first developed in the Bell System in the United States, and became known under the trademark Touch-Tone for use in push-button telephones, starting in 1963. The DTMF frequencies are standardized in ITU-T Recommendation Q.23. The signaling system is also known as ''MF4'' in the United Kingdom, as ''MFV'' in Germany, and ''Digitone'' in Canada. Touch-tone dialing with a telephone keypad gradually replaced the use of rotary dials and has become the industry standard in telephony to control equipment and signal user intent. The signaling on trunks in the telephone network uses a different type of multi-frequency signaling. Multifrequency signaling Before the development of DTMF, telephone numbers were dialed with rotary dials ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continuous-phase Frequency-shift Keying
Continuous phase modulation (CPM) is a method for modulation of data commonly used in wireless modems. In contrast to other coherent digital phase modulation techniques where the carrier phase abruptly resets to zero at the start of every symbol (e.g. M- PSK), with CPM the carrier phase is modulated in a continuous manner. For instance, with QPSK the carrier instantaneously jumps from a sine to a cosine (i.e. a 90 degree phase shift) whenever one of the two message bits of the current symbol differs from the two message bits of the previous symbol. This discontinuity requires a relatively large percentage of the power to occur outside of the intended band (e.g., high fractional out-of-band power), leading to poor spectral efficiency. Furthermore, CPM is typically implemented as a constant-envelope waveform, i.e., the transmitted carrier power is constant. Therefore, CPM is attractive because the phase continuity yields high spectral efficiency, and the constant envelope yields exc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numerically-controlled Oscillator
A numerically controlled oscillator (NCO) is a digital signal generator which creates a synchronous (i.e., clocked), discrete-time, discrete-valued representation of a waveform, usually sinusoidal. NCOs are often used in conjunction with a digital-to-analog converter (DAC) at the output to create a direct digital synthesizer (DDS). Numerically controlled oscillators offer several advantages over other types of oscillators in terms of agility, accuracy, stability and reliability. NCOs are used in many communications systems including digital up/down converters used in 3G wireless and software radio systems, digital phase-locked loops, radar systems, drivers for optical or acoustic transmissions, and multilevel Frequency-shift keying, FSK/Phase-shift keying, PSK modulators/demodulators. Operation An NCO generally consists of two parts: *A ''phase accumulator'' (PA), which adds to the value held at its output a frequency control value at each clock sample. *A ''phase-to-amplitude c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prescaler
A prescaler is an electronic counting circuit used to reduce a high frequency electrical signal to a lower frequency by integer division. The prescaler takes the basic timer clock frequency (which may be the CPU clock frequency or may be some higher or lower frequency) and divides it by some value before feeding it to the timer, according to how the prescaler register(s) are configured. The prescaler values, referred to as prescales, that may be configured might be limited to a few fixed values (powers of 2), or they may be any integer value from 1 to 2^P, where P is the number of prescaler bits. The purpose of the prescaler is to allow the timer to be clocked at the rate a user desires. For shorter (8 and 16-bit) timers, there will often be a tradeoff between resolution (high resolution requires a high clock rate) and range (high clock rates cause the timer to overflow more quickly). For example, one cannot (without some tricks) achieve 1 μs resolution and a 1 sec maxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrature Encoder
An incremental encoder is a linear or rotary electromechanical device that has two output signals, ''A'' and ''B'', which issue pulses when the device is moved. Together, the ''A'' and ''B'' signals indicate both the occurrence of and direction of movement. Many incremental encoders have an additional output signal, typically designated ''index'' or ''Z'', which indicates the encoder is located at a particular reference position. Also, some encoders provide a status output (typically designated ''alarm'') that indicates internal fault conditions such as a bearing failure or sensor malfunction. Unlike an absolute encoder, an incremental encoder does not indicate absolute position; it only reports changes in position and the corresponding direction of movement for each change. Consequently, to determine absolute position at any particular moment, it is necessary to send the encoder signals to an '' incremental encoder interface'', which in turn will "track" and report the encoder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Mice
A computer mouse (plural mice; also mouses) is a hand-held pointing device that detects Plane (mathematics), two-dimensional motion relative to a surface. This motion is typically translated into the motion of the Cursor (user interface)#Pointer, pointer (called a cursor) on a computer monitor, display, which allows a smooth control of the graphical user interface of a computer. The first public demonstration of a mouse controlling a computer system was done by Doug Engelbart in 1968 as part of the Mother of All Demos. Mice originally used two separate wheels to directly track movement across a surface: one in the x-dimension and one in the Y. Later, the standard design shifted to use a ball rolling on a surface to detect motion, in turn connected to internal rollers. Most modern mice use optical mouse, optical movement detection with no moving parts. Though originally all mice were connected to a computer by a cable, many modern mice are cordless, relying on short-range rad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bi-quinary Coded Decimal
Bi-quinary coded decimal is a numeral encoding scheme used in many abacuses and in some early computers, notably the Colossus. The term ''bi-quinary'' indicates that the code comprises both a two-state (''bi'') and a five-state (''quin''ary) component. The encoding resembles that used by many abacuses, with four beads indicating the five values either from 0 through 4 or from 5 through 9 and another bead indicating which of those ranges (which can alternatively be thought of as +5). Several human languages, most notably Fula and Wolof also use biquinary systems. For example, the Fula word for 6, ''jowi e go'o'', literally means ''five lusone''. Roman numerals use a symbolic, rather than positional, bi-quinary base, even though Latin is completely decimal. The Korean finger counting system Chisanbop uses a bi-quinary system, where each finger represents a one and a thumb represents a five, allowing one to count from 0 to 99 with two hands. One advantage of one bi-quina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colossus Computer
Colossus was a set of computers developed by British cryptanalysis, codebreakers in the years 1943–1945 to help in the cryptanalysis of the Lorenz cipher. Colossus used vacuum tube, thermionic valves (vacuum tubes) to perform Boolean algebra (logic), Boolean and counting operations. Colossus is thus regarded as the world's first computer programming, programmable, electronics, electronic, digital electronics, digital computer, although it was programmed by switches and plugs and not by a stored-program computer, stored program. Colossus was designed by General Post Office (GPO) research telephone engineer Tommy Flowers based on plans developed by mathematician Max Newman at the Government Code and Cypher School at Bletchley Park. Alan Turing's use of probability in cryptanalysis (see Banburismus) contributed to its design. It has sometimes been erroneously stated that Turing designed Colossus to aid the cryptanalysis of the Enigma. (Turing's machine that helped decode Enigma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heath Robinson (codebreaking Machine)
Heath Robinson was a machine used by British codebreakers at the Government Code and Cypher School at Bletchley Park during World War II in cryptanalysis of the Lorenz cipher. This achieved the decryption of messages in the German teleprinter cipher produced by the Lorenz SZ40/42 in-line cipher machine. Both the cipher and the machines were called "Tunny" by the codebreakers, who named different German teleprinter ciphers after fish. It was mainly an electro-mechanical machine, containing no more than a couple of dozen valves (vacuum tubes), and was the predecessor to the electronic Colossus computer. It was dubbed "Heath Robinson" by the Wrens who operated it, after cartoonist William Heath Robinson, who drew immensely complicated mechanical devices for simple tasks, similar to (and somewhat predating) Rube Goldberg in the U.S. The functional specification of the machine was produced by Max Newman. The main engineering design was the work of Frank Morrell at the Post Off ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geiger Counter
A Geiger counter (, ; also known as a Geiger–Müller counter or G-M counter) is an electronic instrument for detecting and measuring ionizing radiation with the use of a Geiger–Müller tube. It is widely used in applications such as radiation dosimetry, radiological protection, experimental physics and the nuclear industry. "Geiger counter" is often used generically to refer to any form of dosimeter (or, ''radiation-measuring device''), but scientifically, a Geiger counter is only one specific type of dosimeter. It detects ionizing radiation such as alpha particles, beta particles, and gamma rays using the ionization effect produced in a Geiger–Müller tube, which gives its name to the instrument. In wide and prominent use as a hand-held radiation survey instrument, it is perhaps one of the world's best-known radiation detection instruments. The original detection principle was realized in 1908 at the University of Manchester, but it was not until the development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
