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Action Computer Enterprise
Action Computer Enterprise, Inc. (ACE), was an American computer company that was active from 1978 to 1990. The company delivered one of the first multi-user-capable microcomputers, the Discovery 1600, in 1978. History Foundation (1978–1979) Action Computer Enterprise was co-founded by four friends, including Herbert L. Siegel (February 27, 1938 – August 16, 2016), Kwok M. Ong, and Wing Chung. Ong, Siegel and the fourth founder had met during their employment at Jet Propulsion Laboratory (JPL) in California, while Chung and Ong had met at their alma mater of University of California, Berkeley. Long before starting ACE, Siegel had served in the Peace Corps, teaching in Ethiopia with his wife for two years in the 1960s before returning to the United States to obtain an M.A. in mathematics at UC Berkeley. After graduation, he worked as a programmer for JPL, the Los Angeles County Registrar-Recorder, and the Los Angeles County General, developing navigation strategies for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pasadena, California
Pasadena ( ) is a city in Los Angeles County, California, United States, northeast of downtown Los Angeles. It is the most populous city and the primary cultural center of the San Gabriel Valley. Old Pasadena is the city's original commercial district. Its population was 138,699 at the 2020 census, making it the 45th-largest city in California and the ninth-largest in Los Angeles County. Pasadena was incorporated on June 19, 1886, 36 years after the city of Los Angeles but still one of the first in what is now Los Angeles County. Pasadena is home to many scientific, educational, and cultural institutions, including the California Institute of Technology, Pasadena City College, Kaiser Permanente Bernard J. Tyson School of Medicine, Fuller Theological Seminary, Theosophical Society, Parsons Corporation, Art Center College of Design, the Planetary Society, Pasadena Playhouse, the Ambassador Auditorium, the Norton Simon Museum, and the USC Pacific Asia Museum. Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-100 Bus
The S-100 bus or Altair bus, later standardized as IEEE 696-1983 ''(inactive-withdrawn)'', is an early computer bus designed in 1974 as a part of the Altair 8800. The bus was the first industry standard expansion bus for the microcomputer industry. computers, consisting of processor and peripheral cards, were produced by a number of manufacturers. The bus formed the basis for homebrew computers whose builders (e.g., the Homebrew Computer Club) implemented drivers for CP/M and MP/M. These microcomputers ran the gamut from hobbyist toy to small business workstation and were common in early home computers until the advent of the IBM PC. Architecture The bus is a passive backplane of 100-pin printed circuit board edge connectors wired in parallel. Circuit cards measuring serving the functions of CPU, memory, or I/O interface plugged into these connectors. The bus signal definitions closely follow those of an 8080 microprocessor system, since the Intel 8080 microproce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star Topology
A star network is an implementation of a spoke–hub distribution paradigm in computer networks. In a star network, every host is connected to a central hub. In its simplest form, one central hub acts as a conduit to transmit messages. The star network is one of the most common computer network topologies. Network The hub and hosts, and the transmission lines between them, form a graph with the topology of a star. Data on a star network passes through the hub before continuing to its destination. The hub manages and controls all functions of the network. It also acts as a repeater for the data flow. In a typical network the hub can be a network switch, Ethernet hub, wireless access point or a router The star topology reduces the impact of a transmission line failure by independently connecting each host to the hub. Each host may thus communicate with all others by transmitting to, and receiving from, the hub. The failure of a transmission line linking any host to the hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Local Area Network
A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, campus, or building, and has its network equipment and interconnects locally managed. LANs facilitate the distribution of data and sharing network devices, such as printers. The LAN contrasts the wide area network (WAN), which not only covers a larger geographic distance, but also generally involves Leased line, leased telecommunication circuits or Internet links. An even greater contrast is the Internet, which is a system of globally connected business and personal computers. Ethernet and Wi-Fi are the two most common technologies used for local area networks; historical network technologies include ARCNET, Token Ring, and LocalTalk. Cabling Most wired network infrastructures utilize Category 5 cable, Category 5 or Category 6 cable, Category 6 twisted pair cabling with RJ45 (telecommunications), RJ45 compatible terminations. This medium provides physical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ban Phai District
Ban Phai (, ; , ) is a district (''amphoe'') of Khon Kaen province, northeastern Thailand. Geography Neighboring districts are (from the south clockwise): Pueai Noi, Nong Song Hong, Non Sila, Chonnabot, Mancha Khiri, and Ban Haet of Khon Kaen Province; Kosum Phisai and Kut Rang of Maha Sarakham province. History Originally named Ban Keng (บ้านเกิ้ง), the area was at first a subdistrict (''tambon'') of Chonnabot district. In 1928 the minor district (''king amphoe'') Ban Phai was established consisting of three subdistricts split off from Chonnabot. It was upgraded to a full district on 1 February 1940. In 1946 Chonnabot was downgraded to be a part of Ban Phai District, until it was reestablished in 1966. Economy , Thai sugar giant, the Mitr Phol Group, plans to construct a sugarcane mill and biomass power plant in the district. The initiative will occupy of three of the province's neighbouring districts: Ban Phai, Chonnabot, and Non Sila. The opera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 8087
The Intel 8087, announced in 1980, was the first floating-point coprocessor for the 8086 line of microprocessors. The purpose of the chip was to speed up floating-point arithmetic operations, such as addition, subtraction, multiplication, division, and square root. It also computes transcendental functions such as exponential, logarithmic or trigonometric calculations. The performance enhancements were from approximately 20% to over 500%, depending on the specific application. The 8087 could perform about 50,000 FLOPS using around 2.4 watts. The 8087 was an advanced integrated circuit, pushing the limits of manufacturing technology of the period. Basic operations on the 8087 such as addition and subtraction can take over 100 machine cycles to execute and some instructions exceed 1000 cycles. The chip lacks a hardware multiplier and implements calculations using the CORDIC algorithm. Sales of the 8087 received a significant boost when a coprocessor socket was incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 8086
The 8086 (also called iAPX 86) is a 16-bit computing, 16-bit microprocessor chip designed by Intel between early 1976 and June 8, 1978, when it was released. The Intel 8088, released July 1, 1979, is a slightly modified chip with an external 8-bit Bus (computing), data bus (allowing the use of cheaper and fewer supporting Integrated circuit, ICs),Fewer TTL buffers, latches, multiplexers (although the amount of TTL logic was not drastically reduced). It also permits the use of cheap 8080-family ICs, where the 8254 CTC, Intel 8255, 8255 PIO, and 8259 PIC were used in the IBM PC design. In addition, it makes PCB layout simpler and boards cheaper, as well as demanding fewer (1- or 4-bit wide) DRAM chips. and is notable as the processor used in the original IBM Personal Computer, IBM PC design. The 8086 gave rise to the x86 architecture, which eventually became Intel's most successful line of processors. On June 5, 2018, Intel released a limited-edition CPU celebrating the 40th anniv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiprocessing
Multiprocessing (MP) is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There are many variations on this basic theme, and the definition of multiprocessing can vary with context, mostly as a function of how CPUs are defined ( multiple cores on one die, multiple dies in one package, multiple packages in one system unit, etc.). A multiprocessor is a computer system having two or more processing units (multiple processors) each sharing main memory and peripherals, in order to simultaneously process programs. A 2009 textbook defined multiprocessor system similarly, but noted that the processors may share "some or all of the system’s memory and I/O facilities"; it also gave tightly coupled system as a synonymous term. At the operating system level, ''multiprocessing'' is sometimes used to refer to the executi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Memory Access
Direct memory access (DMA) is a feature of computer systems that allows certain hardware subsystems to access main system computer memory, memory independently of the central processing unit (CPU). Without DMA, when the CPU is using programmed input/output, it is typically fully occupied for the entire duration of the read or write operation, and is thus unavailable to perform other work. With DMA, the CPU first initiates the transfer, then it does other operations while the transfer is in progress, and it finally receives an interrupt from the DMA controller (DMAC) when the operation is done. This feature is useful at any time that the CPU cannot keep up with the rate of data transfer, or when the CPU needs to perform work while waiting for a relatively slow I/O data transfer. Many hardware systems use DMA, including disk drive controllers, graphics cards, network cards and sound cards. DMA is also used for intra-chip data transfer in some multi-core processors. Computers that h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random-access Memory
Random-access memory (RAM; ) is a form of Computer memory, electronic computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A random-access memory device allows data items to be read (computer), read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks and Magnetic tape data storage, magnetic tape), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement. In today's technology, random-access memory takes the form of integrated circuit (IC) chips with MOSFET, MOS (metal–oxide–semiconductor) Memory cell (computing), memory cells. RAM is normally associated with Volatile memory, volatile types of memory where s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zilog Z80A
The Zilog Z80 is an 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be software-compatible with the Intel 8080, offering a compelling alternative due to its better integration and increased performance. Along with the 8080's seven registers and flags register, the Z80 introduced an alternate register set, two 16-bit index registers, and additional instructions, including bit manipulation and block copy/search. Originally intended for use in embedded systems like the 8080, the Z80's combination of compatibility, affordability, and superior performance led to widespread adoption in video game systems and home computers throughout the late 1970s and early 1980s, helping to fuel the personal computing revolution. The Z80 was used in iconic products such as the Osborne 1, Radio Shack TRS-80, ColecoVision, ZX Spectrum, Sega's Master System and the ''Pac-Man'' arcade cabinet. In th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CP/M-86
CP/M-86 is a discontinued version of the CP/M operating system that Digital Research (DR) made for the Intel 8086 and Intel 8088. The system commands are the same as in CP/M-80. Executable files used the relocatable .CMD file format. Digital Research also produced a multi-user multitasking operating system compatible with CP/M-86, MP/M-86, which later evolved into Concurrent CP/M-86. When an emulator was added to provide PC DOS compatibility, the system was renamed Concurrent DOS, which later became Multiuser DOS, of which REAL/32 is the latest incarnation. The FlexOS, DOS Plus, and DR DOS families of operating systems started as derivations of Concurrent DOS as well. History Digital Research's CP/M-86 was originally announced to be released in November 1979, but was delayed repeatedly. When IBM contacted other companies to obtain components for the IBM PC, the as-yet unreleased CP/M-86 was its first choice for an operating system because CP/M had the most applica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
