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MASSCOMP
The Massachusetts Computer Corporation (MASSCOMP) was a computer manufacturer based in Westford, Massachusetts. Originally conceived by C. Forbes Dewey of MIT and inventor Chester Schuler, it was founded formally in 1981. Its target market was real-time computing, with a focus on high-speed data acquisition. Its major innovation was that it created the first widely available computer product which was able to sample analog signals at one million samples per second and store the resulting data to disk continuously. Given the technology available at the time— Motorola 68000 series CPUs of only a few megahertz in speed and slow disk drives—this product represented quite a technological achievement. The MASSCOMP MC-500 is a 68000-based microcomputer running a real-time variant of the Unix operating system. For a small company, MASSCOMP incorporated a number of ambitious and innovative projects in addition to Real-Time Unix, including their own C and Fortran compiler, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concurrent Computer Corporation
Concurrent Computer Corporation was an American computer company, in existence from 1985 to 2017, that made real-time computing and parallel processing systems. Its products powered a variety of applications including process control, simulators, data acquisition, and video-on-demand. It was based in Monmouth County, New Jersey, initially, and then later in Fort Lauderdale, Florida and Duluth, Georgia. Origins and initial efforts The company was created in November 1985 when the computing division of Perkin-Elmer, the Data Systems Group, was spun off as a separate company. The computing group, which had started out as the company Interdata before Perkin-Elmer acquired it in 1974, had been profitable with sales of $259 million, but had tended to have reduced visibility within the computing industry due to being owned by a diversified parent. At first, the new company was a wholly owned subsidiary of Perkin-Elmer, but with the intentions of putting a minority ownership in the compan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PerkinElmer
PerkinElmer, Inc., previously styled Perkin-Elmer, is an American global corporation focused in the business areas of diagnostics, life science research, food, environmental and industrial testing. Its capabilities include detection, imaging, informatics, and service. PerkinElmer produces analytical instruments, genetic testing and diagnostic tools, medical imaging components, software, instruments, and consumables for multiple end markets. PerkinElmer is part of the S&P 500 Index and operates in 190 countries. History Founding Richard Perkin was attending the Pratt Institute in Brooklyn to study chemical engineering, but left after a year to try his hand on Wall Street. Still interested in the sciences, he gave public lectures on various topics. Charles Elmer ran a firm that supplied court reporters and was nearing retirement when he attended one of Perkin's lectures on astronomy being held at the Brooklyn Institute of Arts and Sciences. The two struck up a friendship ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Real-time Operating System
A real-time operating system (RTOS) is an operating system (OS) for real-time applications that processes data and events that have critically defined time constraints. An RTOS is distinct from a time-sharing operating system, such as Unix, which manages the sharing of system resources with a scheduler, data buffers, or fixed task prioritization in a multitasking or multiprogramming environment. Processing time requirements need to be fully understood and bound rather than just kept as a minimum. All processing must occur within the defined constraints. Real-time operating systems are event-driven and preemptive, meaning the OS is capable of monitoring the relevant priority of competing tasks, and make changes to the task priority. Event-driven systems switch between tasks based on their priorities, while time-sharing systems switch the task based on clock interrupts. Characteristics A key characteristic of an RTOS is the level of its consistency concerning the amount of time it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Junk Bond
In finance, a high-yield bond (non-investment-grade bond, speculative-grade bond, or junk bond) is a bond that is rated below investment grade by credit rating agencies. These bonds have a higher risk of default or other adverse credit events, but offer higher yields than investment-grade bonds in order to compensate for the increased risk. Default risk As indicated by their lower credit ratings, high-yield debt entails more risk to the investor compared to investment grade bonds. Investors require a greater yield to compensate them for investing in the riskier securities. In the case of high-yield bonds, the risk is largely that of default: the possibility that the issuer will be unable to make scheduled interest and principal payments in a timely manner. The default rate in the high-yield sector of the U.S. bond market has averaged about 5% over the long term. During the liquidity crisis of 1989-90, the default rate was in the 5.6% to 7% range. During the pandemic of 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C (programming Language)
C (''pronounced like the letter c'') is a General-purpose language, general-purpose computer programming language. It was created in the 1970s by Dennis Ritchie, and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted CPUs. It has found lasting use in operating systems, device drivers, protocol stacks, though decreasingly for application software. C is commonly used on computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems. A successor to the programming language B (programming language), B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the measuring programming language popularity, most widely used programming languages, with C compilers avail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley (Berkeley Software Distribution, BSD), Microsoft (Xenix), Sun Microsystems (SunOS/Solaris (operating system), Solaris), Hewlett-Packard, HP/Hewlett Packard Enterprise, HPE (HP-UX), and IBM (IBM AIX, AIX). In the early 1990s, AT&T sold its rights in Unix to Novell, which then sold the UNIX trademark to The Open Group, an industry consortium founded in 1996. The Open Group allows the use of the mark for certified operating systems that comply with the Single UNIX Specification (SUS). Unix systems are chara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megahertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one hertz is the reciprocal of one second. It is named after Heinrich Hertz, Heinrich Rudolf Hertz (1857–1894), the first person to provide conclusive proof of the existence of electromagnetic waves. Hertz are commonly expressed in metric prefix, multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. The units are sometimes also used as a representation of the photon energy, energy of a photon, via the Planck relation ''E'' = ''hν'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer
A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as Computer program, programs. These programs enable computers to perform a wide range of tasks. A computer system is a nominally complete computer that includes the Computer hardware, hardware, operating system (main software), and peripheral equipment needed and used for full operation. This term may also refer to a group of computers that are linked and function together, such as a computer network or computer cluster. A broad range of Programmable logic controller, industrial and Consumer electronics, consumer products use computers as control systems. Simple special-purpose devices like microwave ovens and remote controls are included, as are factory devices like industrial robots and computer-aided design, as well as general-purpose devi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Processing Unit
A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and input/output (I/O) operations specified by the instructions in the program. This contrasts with external components such as main memory and I/O circuitry, and specialized processors such as graphics processing units (GPUs). The form, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic–logic unit (ALU) that performs arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the fetching (from memory), decoding and execution (of instructions) by directing the coordinated operations of the ALU, registers and other co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motorola 68000
The Motorola 68000 (sometimes shortened to Motorola 68k or m68k and usually pronounced "sixty-eight-thousand") is a 16/32-bit complex instruction set computer (CISC) microprocessor, introduced in 1979 by Motorola Semiconductor Products Sector. The design implements a 32-bit instruction set, with 32-bit registers and a 16-bit internal data bus. The address bus is 24 bits and does not use memory segmentation, which made it easier to program for. Internally, it uses a 16-bit data arithmetic logic unit (ALU) and two more 16-bit ALUs used mostly for addresses, and has a 16-bit external data bus. For this reason, Motorola termed it a 16/32-bit processor. As one of the first widely available processors with a 32-bit instruction set, and running at relatively high speeds for the era, the 68k was a popular design through the 1980s. It was widely used in a new generation of personal computers with graphical user interfaces, including the Macintosh 128K, Amiga, Atari ST, and X68000. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
