|
R800 (CPU)
The R800 is the central processing unit used in the MSX Turbo-R home computer. The R800 was designed by ASCII Corporation of Japan and built by Mitsui & Co The goal was a modern and pipelined CPU binary compatible with the Z80, and therefore with MSX software, while also maintaining compatibility with older MSX Z80-based hardware. Compatibility During the development of the MSX Turbo R, ASCII Corporation considered various processors, both compatible and incompatible with the Z80, as candidates. At that time, Kazuya Kishioka , a company employee, was researching and developing an ASIC that was a high-speed version of the Z80 and largely customized for the MSX architecture. For software compatibility with older MSX software, the R800 uses the same instruction set as the Z80, with only minor but useful additions, such as 8x8-bit and 16x16-bit multiplication instructions called MULUB (8-bit), and MULUW (16-bit). Also, many of the undocumented Z80 instructions were made official, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R800 02
R8 or R-8 may refer to: * Audi R8, used since 1999 by Audi for Le Mans 24 Hours race cars, and since 2007 for a street legal car ** List of Audi R8 automobiles * Machine_taper#R8, R8 Machine taper, originally designed for Bridgeport Milling Machines * R8 (Rodalies de Catalunya), a commuter rail line bypassing Barcelona, Catalonia, Spain * SEPTA Regional Rail, R8 (SEPTA), a commuter rail line in Philadelphia, United States, which has been split into: ** Chestnut Hill West Line: ''(R8 Chestnut Hill West)'' ** Fox Chase Line: ''(R8 Fox Chase)'' * R8: Contact with combustible material may cause fire, a risk phrase in chemistry * HK R8, a modified version of the Heckler & Koch SL8#HK R8, Heckler & Koch SL8 rifle * Smith & Wesson Model 327, Smith & Wesson M&P R8, a .357 Magnum revolver * HP roman8, an 8-bit character set * Kaliningrad K-8, a medium-range air-to-air missile known as R-8 in service * Kyrgyzstan Airlines, from its IATA airline designators * Leica R8, a 1996 manual focus 35&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zilog Z800
The Zilog Z800 was a 16-bit microprocessor designed by Zilog and meant to be released in 1985. It was instruction compatible with their existing Z80, and differed primarily in having on-chip cache and a memory management unit (MMU) to provide a 16 MB address range. It also added a huge number of new more orthogonal instructions and addressing modes. Zilog essentially ignored the Z800 in favor of their 32-bit Z80000 and the Z800 never entered mass production. After more than five years had elapsed since it was originally introduced, the effort was redubbed the Z280 in 1986.EDN November 27, 1986, p133 An actual product, the Z280 would ship in 1987 with almost the same design as the Z800, but this time implemented in CMOS. The Z800 contrasts with Zilog's first 16-bit effort, the Zilog Z8000, in that the Z800 was intended to be Z80 compatible, while the Z8000 was only Z80-like and did not offer any direct compatibility. Short description There was no expansion of the register set ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random-access Memory
Random-access memory (RAM; ) is a form of 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, 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, CD-RWs, DVD-RWs and the older Magnetic tape data storage, magnetic tapes and drum memory), 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. RAM contains multiplexer, multiplexing and demultiplexing circuitry, to connect the data lines to the addressed storage for reading or writing the entry. Usually more than one bit of storage is accessed by the same address, and RAM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bus (computing)
In computer architecture, a bus (shortened form of the Latin '' omnibus'', and historically also called data highway or databus) is a communication system that transfers data between components inside a computer, or between computers. This expression covers all related hardware components (wire, optical fiber, etc.) and software, including communication protocols. Early computer buses were parallel electrical wires with multiple hardware connections, but the term is now used for any physical arrangement that provides the same logical function as a parallel electrical busbar. Modern computer buses can use both parallel and bit serial connections, and can be wired in either a multidrop (electrical parallel) or daisy chain topology, or connected by switched hubs, as in the case of Universal Serial Bus (USB). Background and nomenclature Computer systems generally consist of three main parts: * The central processing unit (CPU) that processes data, * The memory that holds the p ... [...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] |
Clock Speed
In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the processor's speed. It is measured in the SI unit of frequency hertz (Hz). The clock rate of the first generation of computers was measured in hertz or kilohertz (kHz), the first personal computers (PCs) to arrive throughout the 1970s and 1980s had clock rates measured in megahertz (MHz), and in the 21st century the speed of modern CPUs is commonly advertised in gigahertz (GHz). This metric is most useful when comparing processors within the same family, holding constant other features that may affect performance. Determining factors Binning Manufacturers of modern processors typically charge premium prices for processors that operate at higher clock rates, a practice called binning. For a given CPU, the clock rates are determined at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arithmetic Logic Unit
In computing, an arithmetic logic unit (ALU) is a Combinational logic, combinational digital circuit that performs arithmetic and bitwise operations on integer binary numbers. This is in contrast to a floating-point unit (FPU), which operates on floating point numbers. It is a fundamental building block of many types of computing circuits, including the central processing unit (CPU) of computers, FPUs, and graphics processing units (GPUs). The inputs to an ALU are the data to be operated on, called operands, and a code indicating the operation to be performed; the ALU's output is the result of the performed operation. In many designs, the ALU also has status inputs or outputs, or both, which convey information about a previous operation or the current operation, respectively, between the ALU and external status registers. Signals An ALU has a variety of input and output net (electronics), nets, which are the electrical conductors used to convey Digital signal (electronics), digi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 8080
The Intel 8080 (''"eighty-eighty"'') is the second 8-bit microprocessor designed and manufactured by Intel. It first appeared in April 1974 and is an extended and enhanced variant of the earlier 8008 design, although without binary compatibility.'' Electronic News'' was a weekly trade newspaper. The same advertisement appeared in the May 2, 1974 issue of ''Electronics'' magazine. The initial specified clock rate or frequency limit was 2 MHz, with common instructions using 4, 5, 7, 10, or 11 cycles. As a result, the processor is able to execute several hundred thousand instructions per second. Two faster variants, the 8080A-1 (sometimes referred to as the 8080B) and 8080A-2, became available later with clock frequency limits of 3.125 MHz and 2.63 MHz respectively. The 8080 needs two support chips to function in most applications: the i8224 clock generator/driver and the i8228 bus controller. It is implemented in N-type metal-oxide-semiconductor logic (NMOS) usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EZ80
The Zilog eZ80 is an 8-bit microprocessor from Zilog, introduced in 2001. eZ80 is an updated version of the company's first product, the Z80 microprocessor. Design The eZ80 (like the Z380) is binary compatible with the Z80 and Z180, but almost three times as fast as the original Z80 chip at the same clock frequency. The eZ80 has a three-stage pipeline. Available at up to 50 MHz (2004), the performance is comparable to a Z80 clocked at 150 MHz if fast memory is used (i.e. no wait states for opcode fetches, for data, or for I/O) or even higher in some applications (a 16-bit addition is 11 times as fast as in the original). The eZ80 also supports direct continuous addressing of 16 MB of memory without a memory management unit, by extending most registers (HL, BC, DE, IX, IY, SP, and PC) from 16 to 24 bits. In order to do so, the CPU has a full 24-bit address mode called ADL mode. Z80 register pairs are extended to 24 bits and renamed with U e.g. HL is now HLU et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z380
The Z380 and Z382 are Zilog 16-bit/ 32-bit processor from 1994.https://www.zilog.com/docs/datacomm/pb0075.pdf It is Z80 compatible, but it was released much later than its competitors (the Intel 386 and Motorola 68020) and as a result was never able to gain any significant market leverage. On the other hand, the newer and faster eZ80 family was more successful. The chip supports 32-bit processing with a clock speed of up to 20 MHz. The Z380 is incompatible with Zilog's older Z800 and Z280. As the Z380 is derived from the newer Z180 it is a less mini computer like design than these older processors, with fewer features. Instead, it has a wider ALU and register length of 32-bits. It can therefore address 4 GB directly: * Similar pipelined execution or fetch/execute overlap as the Z280 page 45 * Simpler MMU, without memory protection. * Minimum of 2 clocks/ instruction. This is like the Z280, but also for 32-bit operations. * No on-chip cache Cache, caching, or cachà ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z280
The Zilog Z280 is a 16-bit microprocessor, an enhancement of the Zilog Z80 architecture, introduced in July 1987. It is basically the Z800, renamed, with slight improvements such as being fabricated in CMOS. It was a commercial failure. Zilog added a memory management unit (MMU) to expand the addressing range to 16 MB, features for multitasking and multiprocessor and coprocessor configurations, and 256 bytes of on-chip static RAM, configurable as either a cache for instructions and/or data, or as part of the ordinary address space. It has a huge number of new instructions and addressing modes giving a total of over 2000 combinations. It is capable of efficiently handling 32-bit data operations including hardware multiply, divide, and sign extension. It offers Supervisor and User operating modes, and optionally separate address spaces for instructions and data in both modes (four total possible address spaces). Its internal clock signal can be configured to run at 1, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
