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RCA VP 3000
RCA's VP 3000 Interactive Data Terminals were a family of portable computer terminals housed in compact keyboard-like cases, but notable for their use of a color-coded membrane keyboard. The systems supported color output to a television with 20 and 40 character-per-line modes, and an optional built-in modem. It was first advertised in September 1982. The VP series started life as an upgrade to RCA's COSMAC VIP kit-computer, originally to be known as the VIP II. Unlike the original VIP, which was a bare motherboard for hobbyists, the VIP II would be a complete home computer. Most of the new features were added through a series of expansion cards built into the chassis, most of which already existed as add-on cards for the VIP. Although some marketing material was produced in 1979, and RCA suggested it would be available "some time next year" at a price around $400, the VIP II was never released. Instead, the design was re-purposed as a terminal system by replacing the ROMs with on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Terminal
A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. The teletype was an example of an early-day hard-copy terminal and predated the use of a computer screen by decades. Early terminals were inexpensive devices but very slow compared to punched cards or paper tape for input, yet as the technology improved and video displays were introduced, terminals pushed these older forms of interaction from the industry. A related development was time-sharing systems, which evolved in parallel and made up for any inefficiencies in the user's typing ability with the ability to support multiple users on the same machine, each at their own terminal or terminals. The function of a terminal is typically confined to transcription and input of data; a device with significant local, programmable data-processing capability may be called a "smart terminal" or fat client. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Keyboard
A membrane keyboard is a computer keyboard whose "keys" are not separate, moving parts, as with the majority of other keyboards, but rather are pressure pads that have only outlines and symbols printed on a flat, flexible surface. Very little, if any, tactile feedback is felt when using such a keyboard. Membrane keyboards work by electrical contact between the keyboard surface and the underlying circuits when keytop areas are pressed. These models were used with some early 1980s home computers, enjoying wide adoption in consumer electronics devices. The keyboards are quite inexpensive to mass-produce, and are more resistant against dirt and liquids than most other keyboards. However, due to a low or non-existent tactile feedback, most people have difficulty typing with them, especially when larger numbers of characters are being typed. Chiclet keyboards were a slight improvement, at least allowing individual keys to be felt to some extent. Aside from early hobbyist/kit/home co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COSMAC VIP
The COSMAC VIP (1977) IP means Video Interface Processorwas an early microcomputer that was aimed at video games. Essentially, it was a COSMAC ELF with a supplementary CDP1861/CDP1864 video display chip. For a price of US$275, it could be purchased from RCA by mail order. It came in kit form, and had to be assembled. Its dimensions were 22 x 28 cm, and it had a RCA 1802 processor; along with a crystal clock operating at 1.76 MHz. It had 2 KB (2048 bytes) of RAM, which could be expanded to 4 KB on board, and 32 KB via an expansion slot. Its 5 V DC CDP18S023 power supply had an output of 600 mA. I/O ports could be added to connect to sensors, interface relays, an ASCII keyboard, or a printer. The machine connected to either a video monitor or to a TV with video input or by means of an external RF modulator. The VIP used a CDP1861/CDP1864 video display chip to generate the video output, and sound could be played using its integrated speaker. It had a 100 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Read Only Memory
Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing software that is rarely changed during the life of the system, also known as firmware. Software applications (like video games) for programmable devices can be distributed as plug-in cartridges containing ROM. Strictly speaking, ''read-only memory'' refers to memory that is hard-wired, such as diode matrix or a mask ROM integrated circuit (IC), which cannot be electronically changed after manufacture. Although discrete circuits can be altered in principle, through the addition of bodge wires and/or the removal or replacement of components, ICs cannot. Correction of errors, or updates to the software, require new devices to be manufactured and to replace the installed device. Floating-gate ROM semiconductor memory in the form of erasabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminal Program
A terminal emulator, or terminal application, is a computer program that emulates a video terminal within some other display architecture. Though typically synonymous with a shell or text terminal, the term ''terminal'' covers all remote terminals, including graphical interfaces. A terminal emulator inside a graphical user interface is often called a terminal window. A terminal window allows the user access to a text terminal and all its applications such as command-line interfaces (CLI) and text user interface (TUI) applications. These may be running either on the same machine or on a different one via telnet, ssh, dial-up, or over a direct serial connection. On Unix-like operating systems, it is common to have one or more terminal windows connected to the local machine. Terminals usually support a set of escape sequences for controlling color, cursor position, etc. Examples include the family of terminal control sequence standards known as ECMA-48, ANSI X3.64 or ... [...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 modulating one or more carrier wave signals to encode digital information, while the receiver demodulates the signal to recreate the original digital information. The goal is to produce a 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 bit/s for asynchronous dial connections, 4,800 bit/s for synch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RF Modulator
An RF modulator (or radio frequency modulator) is an electronic device whose input is a baseband signal which is used to modulate a radio frequency source. RF modulators are used to convert signals from devices such as media players, VCRs and game consoles to a format that can be handled by a device designed to receive a modulated RF input, such as a radio or television receiver. History Prior to the introduction of specialised video connector standards such as SCART, TVs were designed to only accept signals through the aerial connector: signals originate at a TV station, are transmitted over the air, and are then received by an antenna and demodulated within the TV. When equipment was developed which could use a television receiver as its display device, such as VCRs, DVD players, early home computers, and video game consoles, the signal was modulated and sent to the RF input connector. The aerial connector is standard on all TV sets, even very old ones. Since later te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Television
Color television or Colour television is a television transmission technology that includes color information for the picture, so the video image can be displayed in color on the television set. It improves on the monochrome or black-and-white television technology, which displays the image in shades of gray (grayscale). Television broadcasting stations and networks in most parts of the world upgraded from black-and-white to color transmission between the 1960s and the 1980s. The invention of color television standards was an important part of the history and technology of television. Transmission of color images using mechanical scanners had been conceived as early as the 1880s. A demonstration of mechanically scanned color television was given by John Logie Baird in 1928, but its limitations were apparent even then. Development of electronic scanning and display made a practical system possible. Monochrome transmission standards were developed prior to World War II, but civ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numeric Keypad
A numeric keypad, number pad, numpad, or ten key, is the palm-sized, usually-17-key section of a standard computer keyboard, usually on the far right. It provides calculator-style efficiency for entering numbers. The idea of a 10-key number pad cluster was originally introduced by Tadao Kashio, the developer of Casio electronic calculators. The numpad's keys are digits to , (addition), ( subtraction), (multiplication) and ( division) symbols, ( decimal point), , and keys.numeric keypad' at FOLDOC Laptop keyboards often do not have a numpad, but may provide numpad input by holding a modifier key (typically labelled ) and operating keys on the standard keyboard. Particularly large laptops (typically those with a 15.6 inch screen or larger) may have space for a real numpad, and many companies sell separate numpads which connect to the host laptop by a USB connection (many of these also add an additional spacebar off to the side of the zero where the thumb is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RS-232
In telecommunications, RS-232 or Recommended Standard 232 is a standard originally introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' ('' data terminal equipment'') such as a computer terminal, and a ''DCE'' ('' data circuit-terminating equipment'' or '' data communication equipment''), such as a modem. The standard defines the electrical characteristics and timing of signals, the meaning of signals, and the physical size and pinout of connectors. The current version of the standard is ''TIA-232-F Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange'', issued in 1997. The RS-232 standard had been commonly used in computer serial ports and is still widely used in industrial communication devices. A serial port complying with the RS-232 standard was once a standard feature of many types of computers. Personal computers used them for c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Port
In computing, a parallel port is a type of interface found on early computers (personal and otherwise) for connecting peripherals. The name refers to the way the data is sent; parallel ports send multiple bits of data at once (parallel communication), as opposed to serial communication, in which bits are sent one at a time. To do this, parallel ports require multiple data lines in their cables and port connectors and tend to be larger than contemporary serial ports, which only require one data line. There are many types of parallel ports, but the term has become most closely associated with the printer port or Centronics port found on most personal computers from the 1970s through the 2000s. It was an industry ''de facto'' standard for many years, and was finally standardized as IEEE 1284 in the late 1990s, which defined the Enhanced Parallel Port (EPP) and Extended Capability Port (ECP) bi-directional versions. Today, the parallel port interface is virtually non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
