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TRS-80 Model 4
The TRS-80 Model 4 is the last Z80-based home computer family by Radio Shack, sold from April 1983 through late 1991. Model 4 Tandy Corporation introduced the TRS-80 Model 4 in April 26th, 1983 as the successor to the TRS-80 Model III. The Model 4 has a faster Z80A 4 MHz CPU, larger video display of 80 columns by 24 rows, bigger keyboard, and can be upgraded to 128KB of RAM. It is compatible with Model III software and CP/M application software. The Model 4 was announced in the same April 1983 press release as was the TRS-80 Model 100 laptop. The two computers were often marketed by Tandy/Radio Shack as a complementary pair. A diskless Model 4 with 16KB RAM cost $999; with 64KB RAM and one single-sided 180K disk drive it cost $1699; with 64KB RAM and two drives it cost $1999. An upgrade for Model III owners cost $799 and provided a new motherboard and keyboard. The Model 4's first appearance in the Radio Shack catalog stated: "Yes, it looks like a Model III, but it's mu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRS-80 Model 4 (modified)
The TRS-80 Model 4 is the last Z80-based home computer family by Radio Shack, sold from April 1983 through late 1991. Model 4 Tandy Corporation introduced the TRS-80 Model 4 in April 26th, 1983 as the successor to the TRS-80 Model III. The Model 4 has a faster Z80A 4 MHz CPU, larger video display of 80 columns by 24 rows, bigger keyboard, and can be upgraded to 128KB of RAM. It is compatible with Model III software and CP/M application software. The Model 4 was announced in the same April 1983 press release as was the TRS-80 Model 100 laptop. The two computers were often marketed by Tandy/Radio Shack as a complementary pair. A diskless Model 4 with 16KB RAM cost $999; with 64KB RAM and one single-sided 180K disk drive it cost $1699; with 64KB RAM and two drives it cost $1999. An upgrade for Model III owners cost $799 and provided a new motherboard and keyboard. The Model 4's first appearance in the Radio Shack catalog stated: "Yes, it looks like a Model III, but it's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tandy Corporation
Tandy Corporation was an American family-owned leather goods company based in Fort Worth, Texas, United States. Tandy Leather was founded in 1919 as a leather supply store. By the end of the 1950s, under the tutelage of then-CEO Charles Tandy, the company expanded into the hobby market, making leather moccasins and coin purses, making huge sales among Scouts, leading to a fast growth in sales. Entering the 1960s, aiming to broaden the company horizon, Charles Tandy acquired a number of craft retail companies, including RadioShack in 1963, then an almost bankrupt chain of electronics stores in Boston. In the 1980s, now led by John Roach as CEO, the corporation started to invest into the personal computer market, being one of the pioneers in the personal computer race, being lauded by the magazine ''Financial World'' as "the driving force at the front-running company in the red-hot personal computer race." In 2000, the Tandy Corporation name was dropped and the entity became t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Research
Digital Research, Inc. (DR or DRI) was a company created by Gary Kildall to market and develop his CP/M operating system and related 8-bit, 16-bit and 32-bit systems like MP/M, Concurrent DOS, FlexOS, Multiuser DOS, DOS Plus, DR DOS and GEM. It was the first large software company in the microcomputer world. Digital Research was originally based in Pacific Grove, California, later in Monterey, California. Overview In 1972, Gary Kildall, an instructor at the Naval Postgraduate School in Monterey, California, began working at Intel as a consultant under the business name Microcomputer Applications Associates (MAA). By 1974, he had developed Control Program/Monitor, or CP/M, the first disk operating system for microcomputers. In 1974 he incorporated as Intergalactic Digital Research, with his wife handling the business side of the operation. The company soon began operating under its shortened name Digital Research. The company's operating systems, starting with CP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hayes Command Set
The Hayes command set (also known as the AT command set) is a specific command language originally developed by Dennis Hayes for the Hayes Smartmodem 300 baud modem in 1981. The command set consists of a series of short text strings which can be combined to produce commands for operations such as dialing, hanging up, and changing the parameters of the connection. The vast majority of dial-up modems use the Hayes command set in numerous variations. The command set covered only those operations supported by the earliest 300 bit/s modems. When new commands were required to control additional functionality in higher speed modems, a variety of one-off standards emerged from each of the major vendors. These continued to share the basic command structure and syntax, but added any number of new commands using some sort of prefix character – & for Hayes and USR, and \ for Microcom, for instance. Many of these were re-standardized on the Hayes extensions after the introduction of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modem
A modulator-demodulator or modem is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. A modem transmits data by Modulation#Digital modulation methods, modulating one or more carrier wave signals to encode digital information, while the receiver Demodulation, demodulates the signal to recreate the original digital information. The goal is to produce a Signal (electronics), signal that can be transmitted easily and decoded reliably. Modems can be used with almost any means of transmitting analog signals, from light-emitting diodes to radio. Early modems were devices that used audible sounds suitable for transmission over traditional telephone systems and leased lines. These generally operated at 110 or 300 bits per second (bit/s), and the connection between devices was normally manual, using an attached telephone handset. By the 1970s, higher speeds of 1,200 and 2,400 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luggable
A portable computer is a computer designed to be easily moved from one place to another and included a display and keyboard together, with a single plug, much like later desktop computers called '' all-in-ones'' (AIO), that integrate the system's internal components into the same case as the display. The first commercially sold portable might be the MCM/70, released 1974. The next major portables were the IBM 5100 (1975), Osborne's CP/M-based Osborne 1 (1981) and Compaq's , advertised as 100% IBM PC compatible Compaq Portable (1983). These luggable computers still required a continuous connection to an external power source; this limitation was later overcome by the laptop. Laptops were followed by lighter models, so that in the 2000s mobile devices and by 2007 smartphones made the term almost meaningless. The 2010s introduced wearable computers such as smartwatches. Portable computers, by their nature, are generally microcomputers. Larger portable computers were common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Creative Computing
''Creative Computing'' was one of the earliest magazines covering the microcomputer revolution. Published from October 1974 until December 1985, the magazine covered the spectrum of hobbyist/home/personal computing in a more accessible format than the rather technically oriented ''Byte (magazine), Byte''. The magazine was created to cover educational-related topics. Early issues include articles on the use of computers in the classroom, various simple programs like madlibs and various programming challenges, mostly in BASIC programming language, BASIC. By the late 1970s, it had moved towards more general coverage as the microcomputer market emerged. Hardware coverage became more common, but type-in programs remained common into the early 1980s. The company published several books, the most successful being ''BASIC Computer Games'', the first million-selling computer book. Their ''Best of Creative Computing'' collections were also popular. ''Creative Computing'' also published so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
InfoWorld
''InfoWorld'' (abbreviated IW) is an information technology media business. Founded in 1978, it began as a monthly magazine. In 2007, it transitioned to a web-only publication. Its parent company today is International Data Group, and its sister publications include '' Macworld'' and ''PC World''. InfoWorld is based in San Francisco, with contributors and supporting staff based across the United States. Since its founding, ''InfoWorld''s readership has largely consisted of IT and business professionals. ''InfoWorld'' focuses on how-to, analysis, and editorial content from a mixture of experienced technology journalists and working technology practitioners. The site averages 4.6 million monthly page views and 1.1 million monthly unique visitors. History The magazine was founded by Jim Warren in 1978 as ''The Intelligent Machines Journal'' (IMJ). It was sold to IDG in late 1979. On 18 February 1980, the magazine name was changed to ''InfoWorld''. In 1986, the Robert X. Cringel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hitachi HD64180
The HD64180 is a Z80-based embedded microprocessor developed by Hitachi with an integrated memory management unit (MMU) and on-chip peripherals. It appeared in 1985. The Hitachi HD64180 "Super Z80" was later licensed to Zilog and sold by them as the Z64180 and with some enhancements as the Zilog Z180. Overview The HD64180 has the following features: * Execution and bus access clock rates up to 10 MHz. * Memory Management Unit supporting 512K bytes of memory (one megabyte for the HD64180 packaged in a PLCC) * I/O space of 64K addresses * 12 new instructions including 8 bit by 8 bit integer multiply, non-destructive AND and illegal instruction trap vector * Two channel Direct Memory Access Controller (DMAC) * Programmable wait state generator * Programmable DRAM refresh * Two channel Asynchronous Serial Communication Interface (ASCI) * Two channel 16-bit Programmable Reload Timer (PRT) * 1-channel Clocked Serial I/O Port (CSI/O) * Programmable Vectored Interrupt Controller The ... [...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] |
DESQview
DESQview (DV) is a text mode multitasking operating environment developed by Quarterdeck Office Systems which enjoyed modest popularity in the late 1980s and early 1990s. Running on top of DOS, it allows users to run multiple programs concurrently in multiple windows. Desq Quarterdeck's predecessor to DESQview was a task switching product called Desq (shipped late April or May 1984) which allows users to switch between running programs. Quarterdeck revamped its package, bringing multitasking in, and adding TopView compatibility. DESQview was released in July 1985, four months before Microsoft released the first version of Windows. It was widely thought to be the first program to bring multitasking and windowing capabilities to DOS, but in fact there was a predecessor, IBM TopView, which shipped March 1985, from which DESQview inherited the pop-up menu. Under DESQview, well-behaved DOS programs can be run concurrently in resizable, overlapping windows (something the first vers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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