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AIM 65
The Rockwell AIM-65 computer is a development computer introduced in 1978 based on the MOS Technology 6502 microprocessor. The AIM-65 is essentially an expanded KIM-1 computer. Available software included a line-oriented machine code monitor, BASIC interpreter, assembler, Pascal, PL/65, and FORTH development system. Available hardware included a floppy disk controller and a backplane for expansion. Features Rockwell advertised the $375 AIM-65, with 1K RAM, as an "easy, inexpensive omputer... for learning, designing, work or just fun". Standard software included the system console monitor software in ROM, called Advanced Interactive Monitor. It featured an assembler, disassembler, setting and viewing memory and registers, starting execution of other programs and more. Single stepping was made possible using non-maskable interrupt (NMI). The command prompt was the less-than sign "". If the thermal printer was turned on, this would be output on a single line. The monitor inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Musée Bolo
The Musée Bolo or Swiss Museum of Computer Science, Digital Culture and Video Games is a private museum dedicated to the digital revolution. Its exhibition space is located on the site of the École Polytechnique Fédérale de Lausanne (EPFL) in Lausanne, Romandy, Switzerland. Its main storage area is located near Lausanne Train Station. Collections Within the museum is a collection of old computers dating from the 1960s to the 1990s in danger of disappearance. This is named Bolo's Computer Museum (BCM), and opened in June 2002. Besides old computers, this collection includes other items associated with old computers, such as peripheral devices, hardware documentation and related books and magazines. Among them is the Contraves Cora anti-aircraft fire control computer. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-maskable Interrupt
In computing, a non-maskable interrupt (NMI) is a hardware interrupt that standard interrupt-masking techniques in the system cannot ignore. It typically occurs to signal attention for non-recoverable hardware errors. Some NMIs may be masked, but only by using proprietary methods specific to the particular NMI. An NMI is often used when response time is critical or when an interrupt should never be disabled during normal system operation. Such uses include reporting non-recoverable hardware errors, system debugging and profiling, and handling of special cases like system resets. Modern computer architectures typically use NMIs to handle non-recoverable errors which need immediate attention. Therefore, such interrupts should not be masked in the normal operation of the system. These errors include non-recoverable internal system chipset errors, corruption in system memory such as parity and ECC errors, and data corruption detected on system and peripheral buses. On some systems, ... [...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 erasab ... [...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] |
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 MOS Technology 6502, 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 International, Rockwell and Synertek. The 6522 was widely used in computers of the 1980s, particularly Commodore International, Commodore's machines, and was also a central part of the designs of the Apple III, Oric#Oric-1, Oric-1 and Oric#Oric Atmos, Oric Atmos, BBC Micro, Sirius Systems Technology, Victor 9000/Sirius 1 and Macintosh, Apple Macintosh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Current Loop Interface
For serial communications, a current loop is a communication interface that uses current instead of voltage for signaling. Current loops can be used over moderately long distances (tens of kilometres), and can be interfaced with optically isolated links. There are a variety of such systems, but one based on a 20 mA current level was used by the Teletype Model 33 and was particularly common on minicomputers and early microcomputer which used these as computer terminals. As a result, most computer terminals also supported this standard into the 1980s. History Long before the RS-232 standard, current loops were used to send digital data in serial form for teleprinters. More than two teleprinters could be connected on a single circuit allowing a simple form of networking.E. A. Parr, ''Industrial Control Handbook'', Industrial Press Inc., 1998, , page 648 Older teleprinters used a 60 mA current loop. Later machines, such as the Teletype Model 33, operated on a lower 20&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QWERTY
QWERTY () is a keyboard layout for Latin-script alphabets. The name comes from the order of the first six Computer keyboard keys#Types, keys on the top left letter row of the keyboard ( ). The QWERTY design is based on a layout created for the Sholes and Glidden typewriter and sold to E. Remington and Sons in 1873. It became popular with the success of the Remington No. 2 of 1878, and remains in ubiquitous use. History The QWERTY layout was devised and created in the early 1870s by Christopher Latham Sholes, a newspaper editor and printer who lived in Kenosha, Wisconsin. In October 1867, Sholes filed a patent application for his early writing machine he developed with the assistance of his friends Carlos Glidden and Samuel W. Soule, Samuel W. Soulé. The first model constructed by Sholes used a piano-like keyboard with two rows of characters arranged alphabetically as shown below: - 3 5 7 9 N O P Q R S T U V W X Y Z 2 4 6 8 . A B C D E F G H I J K L M Sholes struggled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandria, Virginia
Alexandria is an independent city (United States), independent city in the northern region of the Commonwealth (U.S. state), Commonwealth of Virginia, United States. It lies on the western bank of the Potomac River approximately south of Downtown, Washington, D.C., downtown Washington, D.C. In 2020, the population was 159,467. The city's estimated population has grown by 1% annually since 2010 on average. Like the rest of Northern Virginia and Central Maryland, modern Alexandria has been influenced by its proximity to the U.S. capital. It is largely populated by professionals working in the United States federal civil service, federal civil service, in the U.S. Military, U.S. military, or for one of the many private companies which contract to Government contractor, provide services to the federal government. One of Alexandria's largest employers is the United States Department of Defense, U.S. Department of Defense. Another is the Institute for Defense Analyses. In 2005, the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halloween
Halloween or Hallowe'en (less commonly known as Allhalloween, All Hallows' Eve, or All Saints' Eve) is a celebration observed in many countries on 31 October, the eve of the Western Christian feast of All Saints' Day. It begins the observance of Allhallowtide, the time in the liturgical year dedicated to remembering the dead, including saints ( hallows), martyrs, and all the faithful departed. One theory holds that many Halloween traditions were influenced by Celtic harvest festivals, particularly the Gaelic festival Samhain, which are believed to have pagan roots. Some go further and suggest that Samhain may have been Christianized as All Hallow's Day, along with its eve, by the early Church. Other academics believe Halloween began solely as a Christian holiday, being the vigil of All Hallow's Day. Celebrated in Ireland and Scotland for centuries, Irish and Scottish immigrants took many Halloween customs to North America in the 19th century,Brunvand, Jan (editor). ''Ame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wavetable Synthesis
Wavetable synthesis is a sound synthesis technique used to create Periodic function, quasi-periodic waveforms often used in the production of musical tones or Musical note, notes. Development Wavetable synthesis was invented by Max Mathews in 1958 as part of MUSIC-N, MUSIC II. MUSIC II “had four-voice polyphony and was capable of generating sixteen wave shapes via the introduction of a wavetable oscillator.” Hal Chamberlin discussed wavetable synthesis in Byte (magazine), Byte's September 1977 issue. Wolfgang Palm of Palm Products GmbH (PPG) developed his version in the late 1970s and published it in 1979. The technique has since been used as the primary synthesis method in synthesizers built by PPG and Waldorf Music and as an auxiliary synthesis method by Ensoniq and Access Music, Access. It is currently used in hardware synthesizers from Waldorf Music and in software synthesizers for PCs and tablets, including apps offered by PPG and Waldorf, among others. It was also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital-to-analog Converter
In electronics, a digital-to-analog converter (DAC, D/A, D2A, or D-to-A) is a system that converts a digital signal into an analog signal. An analog-to-digital converter (ADC) performs the reverse function. There are several DAC architectures; the suitability of a DAC for a particular application is determined by figures of merit including: resolution, maximum sampling frequency and others. Digital-to-analog conversion can degrade a signal, so a DAC should be specified that has insignificant errors in terms of the application. DACs are commonly used in music players to convert digital data streams into analog audio signals. They are also used in televisions and mobile phones to convert digital video data into analog video signals. These two applications use DACs at opposite ends of the frequency/resolution trade-off. The audio DAC is a low-frequency, high-resolution type while the video DAC is a high-frequency low- to medium-resolution type. Due to the complexity a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raster Graphics
upright=1, The Smiley, smiley face in the top left corner is a raster image. When enlarged, individual pixels appear as squares. Enlarging further, each pixel can be analyzed, with their colors constructed through combination of the values for red, green and blue. In computer graphics and digital photography, a raster graphic represents a two-dimensional picture as a rectangular matrix or grid of square pixels, viewable via a computer display, paper, or other display medium. A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel. Raster images are stored in image files with varying dissemination, production, generation, and acquisition formats. The printing and prepress industries know raster graphics as contones (from ''continuous tones''). In contrast, line art is usually implemented as vector graphics in digital systems. Many raster manipulations map directly onto the mathematical formalisms of linear al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
