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Commodore 1571
The Commodore 1571 is Commodore's high-end 5¼" floppy disk drive, announced in the summer of 1985. With its double-sided drive mechanism, it has the ability to use double-sided, double-density (DS/DD) floppy disks, storing a total of 360 kB per floppy. It also implemented a "burst mode" that doubled transfer speeds, helping address the very slow performance of previous Commodore drives. Earlier Commodore drives used a custom group coded recording format that stored 170 kB per side of a disk. This made it fairly competitive in terms of storage, but limited it to only reading and writing disks from other Commodore machines. The 1571 was designed to partner with the new Commodore 128 (C128), which introduced support for CP/M. Adding double-density MFM encoding allowed the drive to read and write contemporary CP/M disks (and many others). In contrast to its single-sided predecessors, the 1541 and the briefly-available 1570, the 1571 can use both sides of the disk a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floppy Disk
A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined with a fabric that removes dust particles from the spinning disk. Floppy disks store digital data which can be read and written when the disk is inserted into a floppy disk drive (FDD) connected to or inside a computer or other device. The first floppy disks, invented and made by IBM, had a disk diameter of . Subsequently, the 5¼-inch and then the 3½-inch became a ubiquitous form of data storage and transfer into the first years of the 21st century. 3½-inch floppy disks can still be used with an external USB floppy disk drive. USB drives for 5¼-inch, 8-inch, and other-size floppy disks are rare to non-existent. Some individuals and organizations continue to use older equipment to read or transfer data from floppy disks. Floppy di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 1541
The Commodore 1541 (also known as the CBM 1541 and VIC-1541) is a floppy disk drive which was made by Commodore International for the Commodore 64 (C64), Commodore's most popular home computer. The best-known floppy disk drive for the C64, the 1541 is a single-sided 170-kilobyte drive for 5¼" disks. The 1541 directly followed the Commodore 1540 (meant for the VIC-20). The disk drive uses group coded recording (GCR) and contains a MOS Technology 6502 microprocessor, doubling as a disk controller and on-board disk operating system (DOS) processor. The number of sectors per track varies from 17 to 21 (an early implementation of zone bit recording). The drive's built-in disk operating system is CBM DOS 2.6. History Introduction The 1541 was priced at under at its introduction. A C64 plus a 1541 cost about $900, while an Apple II with no disk drive cost $1,295. The first 1541 drives produced in 1982 have a label on the front reading VIC-1541 and have an off-white case to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 8050
The Commodore 8050, Commodore 8250, and Commodore SFD-1001 are 5¼-inch floppy disk drives manufactured by Commodore International, primarily for its 8-bit CBM and PET series of computers. The drives offered improved storage capacities over previous Commodore drive models. Specifications All three models utilize 5¼-inch double-density floppy disks with a track spacing of 100 tracks-per-inch, for a total of 77 logical tracks per side. Data is encoded using Commodore's proprietary group coded recording scheme. Soft sectoring is used for track alignment. Like most other Commodore disk drives, these drives utilize zone bit recording to maintain an average bit density across the entire disk. Formatted capacity is approximately 0.5 megabyte per side, or 1 megabyte (1,066,496 bytes) in 4166 blocks total. The 8050 is a single-sided drive, whereas the 8250 and SFD-1001 are dual-sided drives. Dual-sided drives can fully read and write to disks formatted by single-sided drives, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 4040
The Commodore 4040 is the replacement for the previous models 2040 (U.S.) and 3040 (Europe). It's a dual-drive 5¼" floppy disk subsystem for Commodore Business Machines. It uses a wide-case form, and uses the parallel IEEE-488 interface common to Commodore PET/CBM computers. These drive models use a single-density, single-side floppy data storage format similar to that used by the Commodore 1540 & 1541 drives, but with a slightly different data marker indicating which model originally formatted the disk. The low-level disk format is similar enough to allow reading between models, but different enough that one series of drive models cannot reliably write to disks formatted with one of the other model series. A difference of one extra 'header' byte is what causes this write incompatibility. The Group Coded Recording (GCR) scheme of binary encoding is used to store data on the magnetic disk medium. The drive also uses variable bit-clock to enable increased data density on a stan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copy Protected
Copy protection, also known as content protection, copy prevention and copy restriction, describes measures to enforce copyright by preventing the reproduction of software, films, music, and other media. Copy protection is most commonly found on videotapes, DVDs, Blu-ray discs, HD-DVDs, computer software discs, video game discs and cartridges, audio CDs and some VCDs. Some methods of copy protection have also led to criticism because it caused inconvenience for paying consumers or secretly installed additional or unwanted software to detect copying activities on the consumer's computer. Making copy protection effective while protecting consumer rights remains a problem with media publication. Terminology Media corporations have always used the term copy protection, but critics argue that the term tends to sway the public into identifying with the publishers, who favor restriction technologies, rather than with the users. Copy prevention and copy control may be more neutra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Consumer Electronics Show
CES (; formerly an initialism for Consumer Electronics Show) is an annual trade show organized by the Consumer Technology Association (CTA). Held in January at the Las Vegas Convention Center in Winchester, Nevada, United States, the event typically hosts presentations of new products and technologies in the consumer electronics industry. History The first CES was held in June 1967 in New York City. It was a spinoff from the Chicago Music Show, which, until then, had served as the main event for exhibiting consumer electronics. The event had 17,500 attenders and over 100 exhibitors; the kickoff speaker was Motorola chairman Bob Galvin. From 1978 to 1994, CES was held twice each year: once in January in Las Vegas known for ''Winter Consumer Electronics Show (WCES)'' and once in June in Chicago, known as ''Summer Consumer Electronics Show (SCES)''. The winter show was successfully held in Las Vegas in 1995 as planned. However, since the summer Chicago shows were beginning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accolade (company)
Accolade, Inc. (later Infogrames North America, Inc.) was an American video game developer and publisher based in San Jose, California. The company was founded as Accolade in 1984 by Alan Miller and Bob Whitehead, who had previously co-founded Activision in 1979. The company became known for numerous sports game series, including '' HardBall!, Jack Nicklaus'' and '' Test Drive''. By the early 1990s, Accolade saw critical acclaim for '' Star Control'' (1990), as well as strong sales for '' Bubsy'' (1993). However, Sega sued Accolade for creating unauthorized Sega Genesis games by reverse-engineering the console's boot-protection. Accolade won the case on appeal, overturning an injunction from the lower court that had interrupted their sales and development. The founders soon left the company. The new chief executive, Peter Harris, attracted new investment from Time Warner. The following year, Accolade president Jim Barrett replaced him. He focused on existing franchises h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microprose
MicroProse is an American video game publisher and developer founded by Bill Stealey, Sid Meier, and Andy Hollis in 1982. It developed and published numerous games, including starting the ''Civilization'' and '' X-COM'' series. Most of their internally developed titles were vehicle simulation and strategy games. In 1993, the company lost most of its UK-based personnel and became a subsidiary of Spectrum HoloByte. Subsequent cuts and corporate policies led to Sid Meier, Jeff Briggs and Brian Reynolds leaving and forming Firaxis Games in 1996, as MicroProse closed its ex-Simtex development studio in Austin, Texas. In 1998, following an unsuccessful buyout attempt by GT Interactive, the struggling MicroProse (Spectrum HoloByte) became a wholly owned subsidiary of Hasbro Interactive and its development studios in Alameda, California and Chapel Hill, North Carolina were closed the following year. In 2001, MicroProse ceased to exist as an entity and Hasbro Interactive sold the MicroPr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOS Technology 6522
The 6522 Versatile Interface Adapter (VIA) is an integrated circuit that was designed and manufactured by MOS Technology as an I/O port controller for the 6502 family of microprocessors. It provides two bidirectional 8-bit parallel I/O ports, two 16-bit timers (one of which can also operate as an event counter), and an 8-bit shift register for serial communications or data conversion between serial and parallel forms. The direction of each bit of the two I/O ports can be individually programmed. In addition to being manufactured by MOS Technology, the 6522 was second sourced by other companies including Rockwell and Synertek. The 6522 was widely used in computers of the 1980s, particularly Commodore's machines, and was also a central part of the designs of the Apple III, Oric-1 and Oric Atmos, BBC Micro, Victor 9000/Sirius 1 and Apple Macintosh. Video game platforms such as the Vectrex also used the 6522, as did the 1984 through 1989 Corvette digital dash cluster. A high speed, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEEE-488
IEEE 488 is a short-range digital communications 8-bit parallel multi-master interface bus specification developed by Hewlett-Packard as HP-IB (Hewlett-Packard Interface Bus). It subsequently became the subject of several standards, and is generically known as GPIB (General Purpose Interface Bus). Although the bus was created in the late 1960s to connect together automated test equipment, it also had some success during the 1970s and 1980s as a peripheral bus for early microcomputers, notably the Commodore PET. Newer standards have largely replaced IEEE 488 for computer use, but it is still used by some test equipment. Origins In the late 1960s, Hewlett-Packard (HP) manufactured various automated test and measurement instruments, such as digital multimeters and logic analyzers. They developed the ''HP Interface Bus (HP-IB)'' to enable easier interconnection between instruments and controllers (computers and other instruments). The bus was relatively easy to imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shift Register
A shift register is a type of digital circuit using a cascade of flip-flops where the output of one flip-flop is connected to the input of the next. They share a single clock signal, which causes the data stored in the system to shift from one location to the next. By connecting the last flip-flop back to the first, the data can cycle within the shifters for extended periods, and in this form they were used as a form of computer memory. In this role they are very similar to the earlier delay-line memory systems and were widely used in the late 1960s and early 1970s to replace that form of memory. In most cases, several parallel shift registers would be used to build a larger memory pool known as a " bit array". Data was stored into the array and read back out in parallel, often as a computer word, while each bit was stored serially in the shift registers. There is an inherent trade-off in the design of bit arrays; putting more flip-flops in a row allows a single shifter to store ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bit-banging
In computer engineering and electrical engineering, bit banging is a "term of art" for any method of data transmission that employs software as a substitute for dedicated hardware to generate transmitted signals or process received signals. Software directly sets and samples the states of GPIOs (e.g., pins on a microcontroller), and is responsible for meeting all timing requirements and protocol sequencing of the signals. In contrast to bit banging, dedicated hardware (e.g., UART, SPI, I²C) satisfies these requirements and, if necessary, provides a data buffer to relax software timing requirements. Bit banging can be implemented at very low cost, and is commonly used in some embedded systems. Bit banging allows a device to implement different protocols with minimal or no hardware changes. In some cases, bit banging is made feasible by newer, faster processors because more recent hardware operates much more quickly than hardware did when standard communications protocols were c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
