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Jazelle DBX (direct bytecode execution) is an extension that allows some ARM processors to execute Java bytecode in hardware as a third execution state alongside the existing ARM and Thumb modes. Jazelle functionality was specified in the ARMv5TEJ architecture and the first processor with Jazelle technology was the ARM926EJ-S. Jazelle is denoted by a "J" appended to the CPU name, except for post-v5 cores where it is required (albeit only in trivial form) for architecture conformance.

Jazelle RCT (Runtime Compilation Target) is a different technology based on ThumbEE mode; it supports ahead-of-time (AOT) and just-in-time (JIT) compilation with Java and other execution environments.

The most prominent use of Jazelle DBX is by manufacturers of mobile phones to increase the execution speed of Java ME games and applications. A Jazelle-aware Java virtual machine (JVM) will attempt to run Java bytecode in hardware, while returning to the software for more complicated, or lesser-used bytecode operations. ARM claims that approximately 95% of bytecode in typical program usage ends up being directly processed in the hardware.

The published specifications are very incomplete, being only sufficient for writing operating system code that can support a JVM that uses Jazelle. The declared intent is that only the JVM software needs to (or is allowed to) depend on the hardware interface details. This tight binding facilitates the hardware and JVM evolving together without affecting other software. In effect, this gives ARM Holdings considerable control over which JVMs are able to exploit Jazelle. It also prevents open source JVMs from using Jazelle. These issues do not apply to the ARMv7 ThumbEE environment, the nominal successor to Jazelle DBX.

Rekursiv was a computer processor designed by David M. Harland in the mid-1980s for Linn Smart Computing in Glasgow, Scotland. It was one of the few computer architectures intended to implement object-oriented concepts directly in hardware, a form of high-level language computer architecture. The Rekursiv operated directly on objects rather than bits, nibbles, bytes and words. Virtual memory was used as a persistent object store and unusually, the processor instruction set supported recursion (hence the name).

The project originated in an initiative within the hi-fi manufacturer Linn Products to improve its manufacturing automation systems, which at the time ran on a DEC VAX minicomputer. This resulted in the design of Lingo, an object-oriented programming language derived from Smalltalk and ALGOL. Due to the poor performance of Lingo on the VAX, a subsidiary company, Linn Smart Computing Ltd., was formed to develop a new processor to efficiently run Lingo.

The Rekursiv processor consisted of four gate-array chips named Numerik (32-bit ALU), Logik (instruction sequencer), Objekt (object-oriented memory management unit) and Klock (processor clock and support logic). A small number of prototype VMEbus boards, called Hades, comprising these four chips plus 80 MB of RAM were produced. These were intended for installation in a host system such as a Sun-3 workstation.

Although the Rekursiv was never fully developed and was not a commercial success, several Hades boards were used in academic research projects in the UK. The last known copy of a Rekursiv computer ended up at the bottom of the Forth and Clyde canal in Glasgow.

The Pentium FDIV bug is a hardware bug affecting the floating-point unit (FPU) of the early Intel Pentium processors. Because of the bug, the processor would return incorrect binary floating point results when dividing certain pairs of high-precision numbers. The bug was discovered in 1994 by Thomas R. Nicely, a professor of mathematics at Lynchburg College. Missing values in a lookup table used by the FPU's floating-point division algorithm led to calculations acquiring small errors. While these errors would in most use-cases only occur rarely and result in small deviations from the correct output values, in certain circumstances the errors can occur frequently and lead to more significant deviations.

The severity of the FDIV bug is debated. Though rarely encountered by most users (Byte magazine estimated that 1 in 9 billion floating point divides with random parameters would produce inaccurate results), both the flaw and Intel's initial handling of the matter were heavily criticized by the tech community.

In December 1994, Intel recalled the defective processors in what was the first full recall of a computer chip. In its 1994 annual report, Intel said it incurred "a $475 million pre-tax charge ... to recover replacement and write-off of these microprocessors."

A keyset or chorded keyboard (also called a chorded keyset, chord keyboard or chording keyboard) is a computer input device that allows the user to enter characters or commands formed by pressing several keys together, like playing a "chord" on a piano. The large number of combinations available from a small number of keys allows text or commands to be entered with one hand, leaving the other hand free. A secondary advantage is that it can be built into a device (such as a pocket-sized computer or a bicycle handlebar) that is too small to contain a normal-sized keyboard.

A chorded keyboard minus the board, typically designed to be used while held in the hand, is called a keyer. Douglas Engelbart introduced the chorded keyset as a computer interface in 1968 at what is often called "The Mother of All Demos".

Not to be confused with SuperDrive, a trademark used by Apple Computer for various disk drive products or the Super Disc, CD addon for the Super Nintendo Entertainment System.

The SuperDisk LS-120 is a high-speed, high-capacity alternative to the 90 mm (3.5 in), 1.44 MB floppy disk. The SuperDisk hardware was created by 3M's storage products group Imation in 1997, with manufacturing chiefly by Matsushita.

The SuperDisk had little success in North America; with Compaq, Gateway and Dell being three of only a few OEMs who supported it. It was more successful in Asia and Australia, where the second-generation SuperDisk LS-240 drive and disk was released. SuperDisk worldwide ceased manufacturing in 2003.

Bubble memory is a type of non-volatile computer memory that uses a thin film of a magnetic material to hold small magnetized areas, known as bubbles or domains, each storing one bit of data. The material is arranged to form a series of parallel tracks that the bubbles can move along under the action of an external magnetic field. The bubbles are read by moving them to the edge of the material, where they can be read by a conventional magnetic pickup, and then rewritten on the far edge to keep the memory cycling through the material. In operation, bubble memories are similar to delay-line memory systems.

Bubble memory started out as a promising technology in the 1970s, offering performance similar to core memory, memory density similar to hard drives, and no moving parts. This led many to consider it a contender for a "universal memory" that could be used for all storage needs. The introduction of dramatically faster semiconductor memory chips in the early 1970s pushed bubble into the slow end of the scale and it began to be considered mostly as a replacement for disks. The equally dramatic improvements in hard-drive capacity through the early 1980s made it uncompetitive in price terms for mass storage.

Bubble memory was used for some time in the 1970s and 1980s in applications where its non-moving nature was desirable for maintenance or shock-proofing reasons. The introduction of flash storage and similar technologies rendered even this niche uncompetitive, and bubble disappeared entirely by the late 1980s.

The AT&T Hobbit is a microprocessor design that AT&T Corporation developed in the early 1990s. It was based on the company's CRISP (C-language Reduced Instruction Set Processor) design, which in turn grew out of Bell Labs' C Machine design of the late 1980s. C Machine, CRISP and Hobbit were optimized for running the C programming language. The design concentrated on fast instruction decoding, indexed array access and procedure calls. Its processor was partially RISC-like. The project ended in 1994 because the Hobbit failed to achieve commercially viable sales.

The X68000 (Japanese: エックス ろくまんはっせん, Hepburn: Ekkusu Rokuman Hassen) is a home computer created by Sharp Corporation, first released in 1987, sold only in Japan.

The first model features a 10 MHz Motorola 68000 CPU (hence the name), 1 MB of RAM, and no hard drive; the last model was released in 1993 with a 25 MHz Motorola 68030 CPU, 4 MB of RAM, and optional 80 MB SCSI hard drive. RAM in these systems is expandable to 12 MB, though most games and applications do not require more than 2 MB.

An XML appliance is a special-purpose network device used to secure, manage and mediate XML traffic. They are most popularly implemented in service-oriented architectures (SOA) to control XML-based web services traffic, and increasingly in cloud-oriented computing to help enterprises integrate on premises applications with off-premises cloud-hosted applications. XML appliances are also commonly referred to as SOA appliances, SOA gateways, XML gateways, and cloud brokers. Some have also been deployed for more specific applications like Message-oriented middleware. While the originators of the product category deployed exclusively as hardware, today most XML appliances are also available as software gateways and virtual appliances for environments like VMWare.

The IBM System/360 Model 67 (S/360-67) was an important IBM mainframe model in the late 1960s. Unlike the rest of the S/360 series, it included features to facilitate time-sharing applications, notably a Dynamic Address Translation unit, the "DAT box", to support virtual memory, 32-bit addressing and the 2846 Channel Controller to allow sharing channels between processors. The S/360-67 was otherwise compatible with the rest of the S/360 series.