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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 interr ... [...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] |
Amiga 600
The Amiga 600, also known as the A600, is a home computer introduced in March 1992. It is the final Amiga model based on the Motorola 68000 and the 1990 Amiga Enhanced Chip Set. A redesign of the Amiga 500 Plus, it adds the option of an internal hard disk drive and a PCMCIA port. Lacking a numeric keypad, the A600 is only slightly larger than an IBM PC keyboard, weighing approximately 6 pounds. It shipped with AmigaOS 2.0, which was considered more user-friendly than earlier versions of the operating system. Like the A500, the A600 was aimed at the lower end of the market. Commodore intended it to revitalize sales of the A500-related line before the introduction of the 32-bit Amiga 1200. According to Dave Haynie, the A600 "was supposed to be cheaper than the A500, but it came in at about that much more expensive."Haynie, Dave"Re: Amiga CPU is similar to Mac CPU" Usenet (comp.sys.mac.hardware.misc). Posted 4 November 2002, article retrieved from Google Groups archive on 9 November ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zorro III
Zorro (Spanish for 'fox') is a fictional character created in 1919 by American pulp writer Johnston McCulley, appearing in works set in the Pueblo of Los Angeles in Alta California. He is typically portrayed as a dashing masked vigilante who defends the commoners and indigenous peoples of California against corrupt and tyrannical officials and other villains. His signature all-black costume includes a cape, a hat known as a , and a mask covering the upper half of his face. In the stories, Zorro has a high bounty on his head, but is too skilled and cunning for the bumbling authorities to catch, and he also delights in publicly humiliating them. Because of this, the townspeople started calling him ''"El Zorro"'' due to his foxlike cunning and charm. Zorro is an acrobat and an expert in various weapons, but the one he employs most frequently is his rapier, which he uses often to carve the initial "Z" on his defeated foes, and other objects to "sign his work". He is also an accom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zorro II
Zorro II is the general purpose expansion bus used by the Amiga 2000 computer. The bus is mainly a buffered extension of the Motorola 68000 bus, with support for bus mastering DMA. The expansion slots use a 100-pin connector and the card form factor is the same as the IBM PC. Zorro II cards implement the Autoconfig protocol for automatic address space assignment (similar to the later PCI technology on the PC). The prototype "Zorro bus" expansion box for the Amiga 1000 was the basis for the initial Amiga 2000-A model design. This box connected to the Amiga 1000 unbuffered CPU bus card edge connector. Zorro II was succeeded by Zorro III, a 32-bit, asynchronous bus. Memory map External links Amiga Hardware Database- Descriptions and photos of Zorro II cards.Discussion about speed of Zorro Zorro II Zorro II is the general purpose expansion bus used by the Amiga 2000 computer. The bus is mainly a buffered extension of the Motorola 68000 bus, with support for bus mastering DMA. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instructions Per Second
Instructions per second (IPS) is a measure of a computer's processor speed. For complex instruction set computers (CISCs), different instructions take different amounts of time, so the value measured depends on the instruction mix; even for comparing processors in the same family the IPS measurement can be problematic. Many reported IPS values have represented "peak" execution rates on artificial instruction sequences with few branches and no cache contention, whereas realistic workloads typically lead to significantly lower IPS values. Memory hierarchy also greatly affects processor performance, an issue barely considered in IPS calculations. Because of these problems, synthetic benchmarks such as Dhrystone are now generally used to estimate computer performance in commonly used applications, and raw IPS has fallen into disuse. The term is commonly used in association with a metric prefix (k, M, G, T, P, or E) to form kilo instructions per second (kIPS), million instructions p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UAE (emulator)
UAE is a computer emulator which emulates the hardware of Commodore International's Amiga range of computers. Released under the GNU General Public License, UAE is free software. History Bernd Schmidt conceived of an emulator that can run Amiga software when he found that such a task was widely believed to be impossible. Schmidt had written previous programs for Amiga, and was further motivated by the desire to not lose games, demos, and sound modules to switching operating systems. UAE was released in 1995 and was originally called the ''Unusable Amiga Emulator'', due to its inability to boot. In its early stages, it was known as ''Unix Amiga Emulator'' and later with other names as well. Since none of the popular expansions fit any more, the abbreviation no longer stands for anything, and the software is simply known as UAE — this occasionally gets backronymed as Universal Amiga Emulator, Ultimate Amiga Emulator or Ubiquitous Amiga Emulator. Features UAE is almost a fu ... [...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 called a jumper, or more technically, a 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 conducting; they are usually encased in a non-conducti ... [...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 the 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 ... [...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 central processing unit, processor. Memory bandwidth is usually expressed in units of bytes per second, 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 ... [...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. 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. Notable improvements were the '' Super Agnus'' and the ''HiRes Denise'' chips. The sound and floppy controller chip, '' Paula'', remained unchanged from the OCS design. Super Agnus supports 2 MB of Chip RAM, whereas the original Agnus/''Fat Agnus'' and subsequent ''Fatter Agnus'' can address 512 KB and 1 MB, respectively. The ECS Denise chip offers ''Productivity'' (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 on-screen colors. Essentially, a 35 ... [...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 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 Ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amiga CD32
The Amiga CD32 (stylized as Amiga CD32, code-named "Spellbound") is a 32-bit home video game console developed by Commodore and released in Europe, Australia, Canada, and Brazil. It was first announced at the Science Museum in London on July 16, 1993, and was released in September of the same year. The CD32 is part of a family of Amiga computers and other hardware. It uses CD-ROM as its storage medium. It was based on Commodore's Advanced Graphics Architecture chipset, and is of similar specification to the Amiga 1200 personal computer. Using third party devices, it is possible to upgrade the CD32 with a keyboard, floppy drive, hard drive, RAM and mouse, turning it into the equivalent of an Amiga 1200. A hardware MPEG decompression module for playing Video CD was also released. In the Christmas period following its launch, the CD32 accounted for 38% of all CD-ROM drive sales in the UK, exceeding sales of the Mega-CD; however, it was discontinued as Commodore went into bankrup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
