|
Fast RAM
Chip RAM is a commonly used term for the integrated RAM used in Commodore's line of Amiga computers. Chip RAM is shared between the central processing unit (CPU) and the Amiga's dedicated chipset (hence the name). It was also, rather misleadingly, known as "graphics RAM". Direct memory access Under the Amiga architecture, the direct memory access (DMA) controller is integrated into the Agnus (Alice on AGA models) chip. Both the CPU and other members of the chipset have to arbitrate for access to shared RAM via Agnus. This allows the custom chips to perform video, audio, or other DMA operations independently of the CPU. As the 68000 processor used in early Amiga systems usually only accesses memory on every second memory cycle, Agnus operates a system where the "odd" clock cycle is allocated to time-critical custom chip access and the "even" cycle is allocated to the CPU: thus, for average DMA demand, the CPU is not typically blocked from memory access and may run without inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random-access Memory
Random-access memory (RAM; ) is a form of Computer memory, electronic 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 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 and Magnetic tape data storage, magnetic tape), 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. In today's technology, random-access memory takes the form of integrated circuit (IC) chips with MOSFET, MOS (metal–oxide–semiconductor) Memory cell (computing), memory cells. RAM is normally associated with Volatile memory, volatile types of memory where s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amiga 500 Plus
The Amiga 500, also known as the A500, was the first popular version of the Amiga home computer, "redefining the home computer market and making so-called luxury features such as multitasking and colour a standard long before Microsoft or Apple sold these to the masses." It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that of the Commodore 128. Commodore International, Commodore announced the Amiga 500 at the January 1987 winter Consumer Electronics Showat the same time as the high-end Amiga 2000. It was initially available in the Netherlands in April 1987, then the rest of Europe in May. In North America and the UK it was released in October 1987 with a list price. It competed directly against models in the Atari ST line. The Amiga 500 was sold in the same retail outlets as the Commodore 64, as opposed to the computer store-only Amiga 1000. It proved to be Commodore's best-selling m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jumper (computing)
In electronics and particularly computing, a jumper is a short length of conductor used to close, open or bypass part of an electronic circuit. They are typically used to set up or configure printed circuit boards, such as the motherboards of computers. The process of setting a jumper is often called strapping. A strapping option is a hardware configuration setting usually sensed only during power-up or bootstrapping of a device (or even a single chip). Design Jumper pins (points to be connected by the jumper) are arranged in groups called ''jumper blocks'', each group having at least one pair of contact points. An appropriately sized conductive sleeve itself called a jumper, or more technically, a shunt (electrical), shunt jumper, is slipped over the pins to complete the circuit. A two-pin jumper only allows to choose between two Boolean states, whereas a three-pin jumper allows to select between three states. Jumpers must be electrically electrical conductor, conducting; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface-mount Technology
Surface-mount technology (SMT), originally called planar mounting, is a method in which the electrical components are mounted directly onto the surface of a printed circuit board (PCB). An electrical component mounted in this manner is referred to as a surface-mount device (SMD). In industry, this approach has largely replaced through-hole technology construction method of fitting components, in large part because SMT allows for increased manufacturing automation which reduces cost and improves quality. It also allows for more components to fit on a given area of substrate. Both technologies can be used on the same board, with the through-hole technology often used for components not suitable for surface mounting such as large transformers and heat-sinked power semiconductors. An SMT component is usually smaller than its through-hole counterpart because it has either smaller leads or no leads at all. It may have short pins or leads of various styles, flat contacts, a matrix of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chip Carrier
In electronics, a chip carrier is one of several kinds of surface-mount technology packages for integrated circuits (commonly called "chips"). Connections are made on all four edges of a square package; compared to the internal cavity for mounting the integrated circuit, the package overall size is large.Kenneth Jackson, Wolfgang Schroter, (ed), ''Handbook of Semiconductor Technology Volume 2'', Wiley VCH, 2000, , page 627 Types Chip carriers may have either J-shaped metal leads for connections by solder or by a socket, or may be lead-less with metal pads for connections. If the leads extend beyond the package, the preferred description is " flat pack". Chip carriers can be smaller than dual in-line packages and since they use all four edges of the package they can have a larger pin count. Chip carriers may be made of ceramic or plastic. Some forms of chip carrier package are standardized in dimensions and registered with trade industry associations such as JEDEC. Other forms a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual In-line Package
In microelectronics, a dual in-line package (DIP or DIL) is an Semiconductor package, electronic component package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole technology, through-hole mounted to a printed circuit board (PCB) or inserted in a socket. The dual-inline format was invented by Don Forbes, Rex Rice and Bryant Rogers at Fairchild Semiconductor, Fairchild R&D in 1964, when the restricted number of leads available on circular transistor-style packages became a limitation in the use of integrated circuits. Increasingly complex circuits required more signal and power supply leads (as observed in Rent's rule); eventually microprocessors and similar complex devices required more leads than could be put on a DIP package, leading to development of higher-density chip carriers. Furthermore, square and rectangular packages made it easier to route printed-circuit traces beneath the packages. A DIP is usually refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Bandwidth
Memory bandwidth is the rate at which data can be read from or stored into a semiconductor memory by a processor. Memory bandwidth is usually expressed in units of bytes/second, though this can vary for systems with natural data sizes that are not a multiple of the commonly used 8-bit bytes. Memory bandwidth that is advertised for a given memory or system is usually the maximum theoretical bandwidth. In practice the observed memory bandwidth will be less than (and is guaranteed not to exceed) the advertised bandwidth. A variety of computer benchmarks exist to measure sustained memory bandwidth using a variety of access patterns. These are intended to provide insight into the memory bandwidth that a system should sustain on various classes of real applications. Measurement conventions There are three different conventions for defining the quantity of data transferred in the numerator of "bytes/second": #The bcopy convention: counts the amount of data copied from one location ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amiga Enhanced Chip Set
The Enhanced Chip Set (ECS) is the second generation of the Amiga computer's chipset, offering minor improvements over the original chipset (OCS) design. ECS was introduced in 1990 with the launch of the Amiga 3000. Another version was developed around 1994 but was unreleased due to Commodore International filing for bankruptcy. Amigas produced from 1990 onwards featured a mix of OCS and ECS chips, such as later versions of the Amiga 500 and the Commodore CDTV. Other ECS models were the Amiga 500+ in 1991 and lastly the Amiga 600 in 1992. Features The enhanced chip set had two new chips, the 8375 HR Agnus and 8373 HR Denise. The ECS Denise chip offers ''Productivity'' VGA output (640×480 non-interlaced) and ''SuperHiRes'' (1280×200 or 1280×256) display modes (also available in interlaced mode), which are however limited to only 4 bits on-screen colors. The ''Productivity'' output required a multi-sync monitor. It also allowed for a greyscale resolution of 1008 x 800 pixe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Original Chip Set
The Original Chip Set (OCS) is a chipset used in the earliest Commodore Amiga computers and defined the Amiga's graphics and sound capabilities. It was succeeded by the slightly improved Enhanced Chip Set (ECS) and the greatly improved Advanced Graphics Architecture (AGA). The original chipset appeared in Amiga models built between 1985 and 1990: the Amiga 1000, Amiga 2000, Amiga CDTV, and Amiga 500. Overview of chips The chipset which gave the Amiga its unique graphics features consists of three main "custom" chips: ''Agnus'', ''Denise'', and ''Paula''. Both the original chipset and the enhanced chipset were manufactured using NMOS logic technology by Commodore's chip manufacturing subsidiary, MOS Technology. According to Jay Miner, the OCS chipset was fabricated in 5 μm manufacturing process while AGA Lisa was implemented in 1.5 μm process. All three custom chips were originally packaged in 48-pin DIPs; later versions of Agnus, known as Fat Agnus, were pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Bus
In computer architecture, a bus (historically also called a data highway or databus) is a communication system that transfers data between components inside a computer or between computers. It encompasses both hardware (e.g., wires, optical fiber) and software, including communication protocols. At its core, a bus is a shared physical pathway, typically composed of wires, traces on a circuit board, or busbars, that allows multiple devices to communicate. To prevent conflicts and ensure orderly data exchange, buses rely on a communication protocol to manage which device can transmit data at a given time. Buses are categorized based on their role, such as system buses (also known as internal buses, internal data buses, or memory buses) connecting the CPU and memory. Expansion buses, also called peripheral buses, extend the system to connect additional devices, including peripherals. Examples of widely used buses include PCI Express (PCIe) for high-speed internal connections ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amiga CD32
The Amiga CD32 (stylized as Amiga CD32) is a home video game console developed by Commodore as part of the Amiga line, as well as the final hardware to be developed by the company. Released in September 1993 in Europe, Australia, Canada, and Brazil, it was marketed as the "first" 32-bit games console and is essentially a keyboard-less Amiga 1200 personal computer without the I/O ports, but with the addition of a CD-ROM drive in place of floppy and a modified Advanced Graphics Architecture chipset for improved graphical performance. Unlike Commodore's CDTV released two years prior, the CD32 was designed specifically as a games machine. The majority of CD32 game software were ports of existing Amiga 1200 or Amiga 500 titles, and many did not take advantage of CD capabilities like CD music or full-motion video. While it had sold middingly in European markets, the console was withdrawn from sale after only a short time as Commodore filed for bankruptcy in April 1994. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amiga 4000
The Amiga 4000, or A4000, from Commodore is the successor of the Amiga 2000 and Amiga 3000 computers. There are two models: the A4000/040 released in October 1992 with a Motorola 68040 CPU, and the A4000/030 released in April 1993 with a Motorola 68EC030. The Amiga 4000 system design was generally similar to that of the A3000, but introduced the Advanced Graphics Architecture (AGA) chipset with enhanced graphics. The SCSI system from previous Amigas was replaced by the lower-cost Parallel ATA. The original A4000 is housed in a beige horizontal desktop box with a separate keyboard. Later, Commodore released an expanded tower version called the A4000T. The machine is reported to have sold 11,300 units in Germany. Technical information Processor and RAM The stock A4000 shipped with either a Motorola 68EC030 or 68040 CPU, 2 MB of Amiga Chip RAM and up to 16 MB of additional RAM in 32-bit SIMMs. There is a non-functional jumper that was intended to expand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
