BTX (form factor)

BTX (for Balanced Technology eXtended) is a form factor for motherboards, originally intended to be the replacement for the aging ATX motherboard form factor in late 2004 and early 2005.
It was designed to alleviate some of the issues that arose from using newer technologies (which often demand more power and create more heat) on motherboards compliant with the circa 1996 ATX specification. The ATX and BTX standards were both proposed by Intel. However, future development of BTX retail products by Intel was canceled in September 2006 following Intel's decision to refocus on low-power CPUs after suffering scaling and thermal issues with the Pentium 4.
The first company to implement BTX was Gateway Inc, followed by Dell and MPC. The first generation of Apple's Mac Pro used some elements of the BTX design system as well, but was not BTX-compliant, instead using a proprietary form factor.
Enhancements.
picoBTX.
Pico BTX is a motherboard form factor that is meant to miniaturize the BTX standard. Pico BTX motherboards measure . This is smaller than many current "micro"-sized motherboards, hence the name "pico". These motherboards share a common top half with the other sizes in the BTX line, but support only one or two expansion slots, designed for half-height or riser card applications.
Other smaller BTX sizes include: microBTX at and nano BTX at .
The heat sink to be attached to the CPU, called "Thermal Module" throughout the official specification, is no longer attached solely to the motherboard, but to the casing itself, so that the inertial load of its mass during a mechanical shock event can no longer damage the motherboard.
The structural interface between the heat sink and the chassis, is defined as 4 mounting holes with the distances of 4.4 × 2.275 in (55.79 × 111.76 mm) between one another. And since this attachment means is also required to have a certain stiffness, it is called "Support and Retention Module (SRM)" in the specification.
Compatibility with ATX products.
In the first months of production the ATX and BTX motherboards were so similar that moving a BTX motherboard to an ATX case was possible and vice versa. This was possible because the first BTX motherboards were ATX motherboards turned upside down, except for the component location that really were BTX positioning.
Later the BTX form factor had a big change by turning it into a mirror image of the ATX standard. Since the new motherboard design, both standards are incompatible. Basically BTX motherboards are 'leftside-right' compared to ATX and not upside-down as before: i.e. they are mounted on the opposite side of the case. Some computer cases such as the Cooler Master Series (Stackers) were released to support a varying range of motherboard standards such as ATX, BTX, Mini-ATX and so forth, to ease motherboard upgrade without buying a new case; however, all connector and slot standards are identical, including PCI(e) cards, processors, RAM, hard drives, etc.
BTX power supply units can be exchanged with newer ATX12V units, but not with older ATX power supplies that don't have the extra 4-pin 12V connector, which was introduced with the ATX12V standard.
Reception.
The BTX form factor has not been widely adopted despite its improvements over ATX and related standards. As a result, the availability and variety of BTX-compatible components is limited.
One reason for the failure of BTX to gain traction in key markets was the rise of energy-efficient components (CPUs, chipsets and GPUs) which require less power and produce less waste heat, eliminating two of the primary intended benefits of BTX. Another reason was the lack of OEM adopters.
Initially, only Gateway and Dell offered computers with the new format, later HP and Fujitsu-Siemens (now Fujitsu) also offered some BTX-based computers. Most other manufacturers stayed with the ATX standard, and even the handful of manufacturers who did adopt BTX for some products continued to produce the bulk of their machines with the ATX form factor.


Nintendo 2DS

The Nintendo 2DS is a handheld game console produced by Nintendo. Announced in August 2013, the device was released in North America, Europe and Australia on October 12, 2013. The Nintendo 2DS is an entry-level version of the Nintendo 3DS which maintains otherwise identical hardware, similar functionality, and compatibility with software designed for the Nintendo DS and 3DS. However, the 2DS is differentiated by a new slate form factor rather than the clamshell design used by its precursors and by lacking the Nintendo 3DS's signature autostereoscopic 3D display. The 2DS was sold concurrently with existing 3DS models as an incentive to expand the market for Nintendo 3DS games; former Nintendo of America president Reggie Fils-Aimé stated that the 2DS was primarily targeted towards younger players (such as those younger than age 7), whom Nintendo had previously advised not to use the 3D functionality on the 3DS due to potential eye health concerns. The Nintendo 2DS's successor, the New Nintendo 2DS XL, was launched in 2017.
Reception to the Nintendo 2DS was mixed; while Nintendo was praised for how it priced and positioned the 2DS alongside its higher-end counterparts, much of its criticism was directed towards its regressions in comparison to the 3DS, such as a design that some considered less appealing than that of the 3DS, its lower sound quality, and its battery life. However, the 2DS's design was praised by some critics for being more robust and comfortable to hold than the 3DS, especially for its target market. Some critics also felt that the lack of 3D support was an admission by Nintendo that the concept was a gimmick; however, Nintendo has since stated that autostereoscopic 3D would remain a part of their future plans. The Nintendo 2DS was discontinued in Japan in 2019 and in the rest of the world in 2020.
History.
Nintendo officially unveiled the 2DS on August 28, 2013 via a press release; members of the press were given a chance to demo the device in private prior to the announcement. According to Nintendo of America president Reggie Fils-Aimé, the Nintendo 2DS is primarily aimed at a younger demographic than the Nintendo 3DS — particularly, those younger than 7 years old; whom Nintendo had advised not to use the 3D features on the 3DS due to potential eye health concerns. The validity of Nintendo's claims were questioned by vision experts, however, who believed that the 3DS could actually help detect certain eye problems, and felt the warnings were for liability reasons rather than any realistic harm.
With the 2DS, the company aimed to produce a device that would be "new, unique, different, and [bring] more people into this category that we love." Part of this goal was achieved by positioning the device at a lower price point than the 3DS; in the United States, the system retailed at US$129.99 on launch, in comparison to the US$169.99 price of the standard 3DS. By May 2016, the U.S. price had been lowered further to $79.99.
As part of a promotional effort for Nintendo's late-2013 releases, the Nintendo 2DS was featured on "The Nintendo Experience" promotional tour at Simon Malls locations in the United States throughout October and into early November.
Launch.
The Nintendo 2DS was released in North America, Europe and Australia on October 12, 2013, the same day as "Pokémon X" and "Y". In North America, it was available at launch in black models with red or blue bezels, while in Europe and Australia, it was available in white with red bezels, or black with blue bezels. Each console is bundled with a 4 GB SD card and an AC adapter. Matching red and blue carrying case accessories were also released on launch. With the release of the 2DS, Nintendo of America began to phase out the original 3DS, leaving the 2DS and 3DS XL as the only models still actively sold in North America as of its release.
On December 7, 2013, the Nintendo 2DS launched in South Korea, in white/red and black/blue models that respectively included a digital copy of "Pokémon X" or "Y".
A "Sea Green" variant, with a white body and mint green accents, color was released in North America on June 6, 2014 to coincide with the North American release of "Tomodachi Life". "Crystal Red" and "Crystal Blue" versions, which feature a translucent front cover, were released in Europe and North America in November 2014 as a tie-in for "Pokémon Omega Ruby" and "Alpha Sapphire". In North America, the translucent models were also sold at a lower retail price of US$100 as opposed to the base US$129.99 price of the normal 2DS. On August 20, 2015, the U.S. price was permanently lowered to $100, and units began to be bundled with coupons for a digital copy of "Mario Kart 7".
In December 2015, it was announced that the 2DS would be released in Japan on February 27, 2016 to coincide with the Virtual Console release of the original Game Boy "Pokémon" games. They were made available in translucent red, green, blue and yellow versions with colored buttons. Each were bundled with the corresponding "Pokémon" game, a special Home Menu theme, a poster, and a code to obtain Mew on the bundled game, or "Pokémon X", "Y", "Omega Ruby", or "Alpha Sapphire".
On May 11, 2016, Nintendo announced that the U.S. price would be lowered to $79.99 effective May 20, 2016. On September 15, 2016, the 2DS was released in standalone bundles in Japan, in blue, black, red, lavender, and pink color options. On October 5, 2016, Nintendo announced refreshed versions of the stock "Mario Kart 7" 2DS bundles for the U.S. market ("Crimson Red 2" and "Electric Blue 2", based on the new Japanese variants), with "swapped" color schemes featuring red or blue bodies and black bezels.
Hardware.
The Nintendo 2DS's hardware specifications are almost identical to those of the Nintendo 3DS; retaining features such as its GPU, CPU and memory, along with compatibility with games designed for the Nintendo DS and Nintendo 3DS. However, its hardware still contains some slight differences. Unlike the Nintendo 3DS, which uses two display panels, with a lower touchscreen panel and a top dual-layered screen panel capable of displaying autostereoscopic 3D, the Nintendo 2DS uses a single, non-stereoscopic LCD touchscreen, which is overlaid with a frame mimicking the screen dimensions of the 3DS. Despite its inability to display 3D content, the 2DS retains the 3DS's dual cameras for taking photographs in a 3D format. The Nintendo 2DS only has an internal mono speaker, as opposed to the internal stereo speakers of the 3DS, although stereo sound can still be output through the headphone jack.
The Nintendo 2DS's design is a significant departure from that of its precursors; while it is roughly the same size as its counterpart, the 2DS uses a "slate-like" form factor instead of the clamshell form used by the DS and 3DS. Its buttons are positioned towards the center of the device instead of near the lower screen, and its shoulder buttons are concave in shape and relatively thicker than those of the 3DS. The 2DS uses a switch for entering sleep mode in lieu of closing the shell, and the hardware wireless switch was replaced by a software toggle.
The Nintendo 2DS contains the same 1300mAh battery present on regular Nintendo 3DS systems. Despite not supporting the 3DS's automatic brightness setting ("Power Save Mode"), the 2DS was rated by Nintendo as having slightly longer battery life than the 3DS; Nintendo rated the 2DS as being able to play from 3 to 5.5 hours of 3DS games or 5 to 9 hours of DS games on a single charge.
Software and services.
Aside from minor adjustments to reflect its hardware design differences, the system software of the Nintendo 2DS is otherwise identical to that of the 3DS, remaining compatible with all games released for the 3DS (in two-dimensional mode only) and DS (excluding those requiring the Game Boy Advance cartridge slot), and offering online features such as Nintendo Network for multiplayer and online gaming, Nintendo eShop for downloading and purchasing games, and SpotPass and StreetPass.
Reception.
Pre-release.
The Nintendo 2DS received mixed reception upon its announcement. Kotaku felt that the Nintendo 2DS might appeal to a certain niche of people who otherwise would not purchase a Nintendo 3DS, and that the lack of 3D support could indicate a cooling interest in stereoscopic graphics. USA Today noted that some games that were designed with 3D in mind might not be as easily playable without the stereoscopic feature. CNET, meanwhile, called the console an acknowledgement by Nintendo that 3D was an unnecessary feature and even a "tactical mistake". "NBC News" called the 2DS a "peculiar choice" to gamers satisfied with the Nintendo DS line, and feared that it might take resources away from the less successful Nintendo console, the Wii U.
Some technology writers have expressed concern with the physical appearance of the 2DS: CNET considered the console to be significantly less aesthetically pleasing than its other models, though some reviewers have generally found it to be comfortable in the hand. "USA Today" referred to it as "surprisingly comfortable". Kotaku noted that while it may look bulky, it was pleasant to hold even with one hand. It also noted that buttons on the unit were easily accessible, and that their placement on the upper half of the console directs the eye toward the upper screen. Overall, the publication felt that the build quality was good. GamesIndustry also described the controls as considerably more comfortable than that of its predecessors. It also noted that the console had thick shell rather than the thin Nintendo 3DS, and that the lack of a hinge added durability. The publication felt that the design resembled "an unholy union of a Game Boy, the Wii U GamePad, and a DS." "USA Today" and CNET both had some concern over how to protect the screens, since there is no clamshell to close.
In response to the 2DS using one physical display divided to emulate two, Kyle Orland of "Ars Technica" believed that Nintendo had missed an opportunity to produce a full-screen gaming tablet using the 2DS's form factor; which would have enabled future games and apps to use the entire screen area (which he estimated to be around the 5-inch range used by phablets), still allow backwards compatibility with games designed for the folding 3DS and DS, and enhance the ability to port existing smartphone games to the platform. However, Orland also noted that introducing such a product could fragment Nintendo's portable gaming ecosystem for existing 3DS users—and that it was too early in the 3DS's life for Nintendo to introduce a successor. Nearly 3 years after the release of the 2DS, Nintendo would ultimately announce the Nintendo Switch—a "hybrid" gaming tablet with detachable wireless controllers, and support of a docking station for use with a television.
Calling it a "smart move" to redesign the Nintendo 3DS so as to lower costs, "Wired" felt that the 2DS might enable Nintendo to sell the console at a significantly lower price with a significantly higher profit margin.
Post-release.
The Nintendo 2DS has received mixed reviews. While pricing and form-factor were generally considered ideal, the console's aesthetics and battery life were widely criticized. The Telegraph noted that the lack of hinges in the console improved its robustness, and that rounding out the footprint makes it an ideal handheld for children. However, the publication criticized the console's mono speaker, which offered a lower sound quality than its predecessors. It also criticized the battery life, which it described as being the same as the original 3DS model. On the other hand, it praised the screens' brighter display and wider viewing angle, despite their not being as large as those of the 3DS XL. Eurogamer reinforced the idea that the Nintendo 2DS isn't aimed at "seasoned players" or current Nintendo 3DS owners, and felt that the system wasn't produced with aesthetics in mind. The publication also criticized the resistive touchscreen, which felt outdated, the mono speaker and battery life. However, Eurogamer felt that the system is much more comfortable to hold than the Nintendo 3DS and 3DS XL. Analyst Piers Harding-Rolls felt that the Nintendo 2DS would help Nintendo broaden its market, and believes that third-party publishers will have more commitment to the platform moving forward.
Following the system's launch, Nintendo stated that the release of "Sonic Lost World" would boost Nintendo 2DS sales, labeling it as a "must play" title. On October 31, 2013, Nintendo president Satoru Iwata admitted that the Nintendo 2DS lacked awareness among prospective purchasers. Additionally, he went on to say that some potential consumers believed that the product was too large and heavy to carry. However, Iwata stated that the system was well received among those who had purchased it. Despite the 2DS's lack of 3D support, Satoru Iwata insisted, during Nintendo's 2013 third quarter investors Q&A, that the company "will [not] abandon 3D or cease to make new propositions in 3D", as it will continue to sell the existing Nintendo 3DS and 3DS XL platforms. However, "" producer Eiji Aonuma revealed in an interview that the game had minor changes in development due to the lack of 3D on the 2DS.
Sales.
Sales of the Nintendo 2DS surged three weeks after launching in the United Kingdom, after retailers cut on its price due to poor sales. The system was available for around £110, but major retailers including Argos, Amazon and Tesco cut the system's price to under £100 to coincide with the school half-term. As a result, sales of the Nintendo 2DS increased by 64% week-on-week, making it the UK's best selling console of the month, without combining the sales of the Nintendo 3DS and its larger counterpart. During the third quarter of 2013, video game retailer GameStop reported that worldwide hardware sales grew by 15.3%, mainly due to strong Nintendo 2DS and 3DS sales.


Departmental boot image

A departmental boot image is a boot image for any computer that has been enhanced by adding some applications and passwords specific to a task or group or department in an organization. This has many of the advantages of a thin client strategy, but can be done on any operating system base as long as the boot device is large enough to accommodate the boot and applications together.
A typical departmental Windows XP boot image is usually so large that it requires a DVD to store, and may be too large for network booting. Accordingly, it is usually installed on a fixed or removable hard drive kept inside the machine, rather than installed over a network or from a ROM.
There are some boot image control complexity and total cost of operations advantages to using a departmental boot image instead of a common boot image for the entire organization, or a thin client:
Disadvantages include the complexity of creating and managing several large boot images, and determining when a department needs to upgrade its applications. If each user is allowed to do this on their own, then, the discipline soon degrades and the shop will be no easier to manage than one that consists of one-off computers with their own quirks, frequently requiring re-imaging and whose issues are not really diagnosable nor comparable to each other. Some experts believe that any departmental boot image regime degrades rather quickly to this state without extraordinary discipline and controls, and advocate thin clients to ensure such control.
It is however increasingly possible to restrict users from installing "their own" applications on a standard boot image, and to automatically re-install when a variant boot image is detected. While this would be draconian in a large organization with one boot image it is often quite acceptable when the boot image is maintained at a departmental level and users can request that it be upgraded with a minimum of bureaucracy and waiting.


BNU (software)

BNU is a high-performance communications device driver designed to provide enhanced support for serial port communications. The BNU serial port driver was specifically targeted for use with early (late 1980s - 1990s) DOS-based BBS software. The reason for BNU and other similar enhanced serial port drivers was to provide better support for serial communications software than what was offered by the machine's BIOS and/or DOS being used on the machine. Having serial port support as provided by BNU and other similar drivers allowed the communications software programmers to spend more time on the actual applications instead of the depths and details of how to talk to the serial ports and the modems connected to them. Sending communications data across a modem link was a lot more involved than sending data to a serial printer which was basically all that was originally capable of being done with the existing serial port software support.
BNU was written by David Nugent as an experimental driver for serial communications following the FOSSIL specification. David released BNU to the public in 1989 and its use in the BBS world spread rapidly. BNU was one of only two or three available FOSSIL drivers for the IBM PC compatible hardware and MS-DOS/PC DOS operating system. Because of this, BNU has been one of the most widely used MS-DOS FOSSIL communications drivers.
BNU was mainly used with DOS-based Bulletin Board System (BBS) software written in the late 1980s to mid-1990s. It is not used by Windows-based BBS software, but BNU can be used under Windows NTVDM to run DOS-based BBS software under Windows. BNU and other similar drivers were not limited solely to being used in the BBS world. The enhanced capabilities they offered were also used to easily communicate with other serially connected devices for the same reasons that the FOSSIL specification and FOSSIL drivers were originally created. That reason, as noted above, was to separate the details of serial port communications from the actual application. The software's programmers only needed to talk to the serial driver in a standardized way to send and receive their data.
The name "BNU" was originally a rip-off of AT&T's "BNU UUCP", and in that context meant "Basic Networking Utilities". The author of BNU, David Nugent, felt that the acronym was particularly apt for BNU's function. BNU was also called "Bloody Nugent's Utility" because it was written by David Nugent as one of his many BBS related utilities and it was not known at the time what the acronym "BNU" actually stood for.
The BNUFAQ used to be posted in the Fidonet BNU support echo by the author. This saved text file is the last official posting of this FAQ by David Nugent, BNU's author.


Control-V

In computing, Control-V is a key stroke with a variety of uses including generation of a control character in ASCII code, also known as the synchronous idle (SYN) character. The key stroke is generated by pressing the key while holding down the key on a computer keyboard. For MacOS based systems, which lack a key, the common replacement of using the key does in fact work.
Usage.
In many GUI environments, including Microsoft Windows and most desktop environments based on the X Window System, and in applications such as word processing software running in those environments, control-V can be used to paste text or other content (if supported) from the clipboard at the current cursor position. Control-V was one of a handful of keyboard sequences chosen by the program designers at Xerox PARC to control text editing.
IBM Input/output devices utilizing the Bisync link protocol use the SYN character code to signal the beginning of each data frame transmitted.
Unix interactive terminals use Control-V to mean "the next character should be treated literally" (the mnemonic here is "v is for verbatim"). This allows a user to insert a literal Control-C or Control-H or similar control characters that would otherwise be handled by the terminal. This behavior was copied by text editors like vi and Unix shells like bash and tcsh, which offer text editing on the command line.
Representation.
The ASCII and Unicode representation of "Synchronous Idle" is 22 in decimal, which is 26 in octal and 16 in hexadecimal.


PowerPC 400

The PowerPC 400 family is a line of 32-bit embedded RISC processor cores based on the PowerPC or Power ISA instruction set architectures. The cores are designed to fit inside specialized applications ranging from system-on-a-chip (SoC) microcontrollers, network appliances, application-specific integrated circuits (ASICs) and field-programmable gate arrays (FPGAs) to set-top boxes, storage devices and supercomputers.
Applied Micro Circuits Corporation (AMCC) bought assets concerning the 400 family cores from IBM in April 2004 for $227 million, and they now market the processors under their own name. IBM continues evolving the cores while supplying design and foundry services around the cores. Several cores are also available for licensing by OEMs from IBM and Synopsys.
Variants.
PowerPC 403.
Introduced in 1994, the PowerPC 403 was one of the first PowerPC processors. It was the first one targeted strictly to the embedded market. Compared to the other PowerPC processors of the era (PowerPC 601, PowerPC 603 and PowerPC 604), it was at the very low end, lacking a memory management unit (MMU) or floating point unit (FPU), for instance. The core was offered for custom chips and in pre packaged versions, including versions with MMU, speeds ranging from 20 to 80 MHz.
The PowerPC 403 is used in, among other appliances, thin clients, set-top boxes, RAID-controllers, network switches and printers. The first TiVo used a 54 MHz PowerPC 403GCX.
AMCC acquired the design of 403 from IBM in 2004, but have chosen not to market it, instead focusing on the 405 and 440 cores.
PowerPC 401.
While the 403 was popular, it was also too high performance and too costly for some applications, so in 1996 IBM released a bare bones PowerPC core, called PowerPC 401. It has a single issue, three-stage pipeline, with no MMU or DMA and only 2 KB instruction and 1 KB data L1 caches. The design contained just 85,000 transistors in all and operated at up to 100 MHz, drawing only 0.1 W or less. Applications using the 401 core range from set-top boxes and telecom switches to printers and fax machines.
PowerPC 405.
The PowerPC 405 was released in 1998 and was designed for price or performance sensitive low-end embedded system-on-a-chip (SoC) designs. It has a five-stage pipeline, separate 16 KB instruction and data L1 caches, a CoreConnect bus, an Auxiliary Processing Unit (APU) interface for expandability and supports clock rates exceeding 400 MHz. The 405 core adheres to the Power ISA v.2.03 using the Book III-E specification. Both AMCC and IBM are developing and marketing processors using 405 cores. IBM and Synopsys also offers a fully synthesizable core. IBM has announced plans to make the specifications of the PowerPC 405 core freely available to the academic and research community.
PowerPC-405-based applications include digital cameras, modems, set-top boxes (IBM's STB04xxx processors), cellphones, GPS-devices, printers, fax machines, network cards, network switches, storage devices and service processors for servers. Up to two 405 cores are used in Xilinx Virtex-II Pro and Virtex-4 FPGAs. In 2004 Hifn bought IBM's PowerNP network processors that uses 405 cores.
PowerPC 440.
Introduced in 1999, the PowerPC 440 was the first PowerPC core from IBM to include the "Book E" extension to the PowerPC specification. It also included the CoreConnect bus technology designed to be the interface between the parts inside a PowerPC based system-on-a-chip (SoC) device.
It is a high-performance core with separate 32 KB instruction and data L1 caches, a seven-stage out-of-order dual-issue pipeline, supporting speeds of up to 800 MHz and L2 caches up to 256 KB. The core lacks a floating point unit (FPU) but it has an associated four-stage FPU that can be included using the APU (Auxiliary Processing Unit) interface. The 440 core adheres to the Power ISA v.2.03 using the Book III-E specification.
Xilinx currently incorporates one or two cores (depending on the member of the family) into the Virtex-5 FXT FPGA.
Both AMCC and IBM are developing and marketing stand alone processors using 440 cores. IBM and Synopsys also offers fully synthesized cores.
PowerPC 450.
The processing core of the Blue Gene/P supercomputer designed and manufactured by IBM. It is very similar to the PowerPC 440 but few details are disclosed.
PowerPC 460.
Introduced in 2006, the 460 cores are similar to the 440 but reach 1.4 GHz, are developed with multi-core applications in mind and have 24 additional digital signal processing (DSP) instructions. The cores are designed to be low-power but high performance and the 464-H90 is expected to draw only 0.53 W at 1 GHz. The 460 core adheres to Power ISA v.2.03 using the Book III-E specification.
PowerPC 470.
The 470 embedded and customizable core, adhering to the Power ISA v2.05 Book III-E, was designed by IBM together with LSI and implemented in the PowerPC 476FP in 2009. The 476FP core has 32/32 kB L1 cache, dual integer units and a SIMD capable double precision FPU that handles DSP instructions. Emitting 1.6 W at 1.6 GHz on a 45 nm fabrication process. The 9 stage out of order, 5-issue pipeline handles speeds up to 2 GHz, supports the PLB6 bus, up to 1 MB L2 cache and up to 16 cores in SMP configurations.


Job control (Unix)

In Unix and Unix-like operating systems, job control refers to control of jobs by a shell, especially interactively, where a "job" is a shell's representation for a process group. Basic job control features are the suspending, resuming, or terminating of all processes in the job/process group; more advanced features can be performed by sending signals to the job. Job control is of particular interest in Unix due to its multiprocessing, and should be distinguished from job control generally, which is frequently applied to sequential execution (batch processing).
Overview.
When using Unix or Unix-like operating systems via a terminal (or terminal emulator), a user will initially only have a single process running, their login shell. Most tasks (directory listing, editing files, etc.) can easily be accomplished by letting the program take control of the terminal and returning control to the shell when the program exits – formally, by attaching to standard input and standard output to the shell, which reads or writes from the terminal, and catching signals sent from the keyboard, like the termination signal resulting from pressing .
However, sometimes the user will wish to carry out a task while using the terminal for another purpose. A task that is running but is not receiving input from the terminal is said to be running "in the background", while the single task that is receiving input from the terminal is "in the foreground". Job control is a facility developed to make this possible, by allowing the user to start processes in the background, send already running processes into the background, bring background processes into the foreground, and suspend or terminate processes.
The concept of a "job" maps the (shell) concept of a single shell command to the (operating system) concept of the possibly many processes that the command entails. Multi-process tasks come about because processes may create additional child processes, and a single shell command may consist of a pipeline of multiple communicating processes. For example, a command to select lines containing the text "title", sort these alphabetically, and display the result in a pager.
grep title somefile.txt | sort | less
This creates at least three processes: one for , one for , and one for . Job control allows the shell to control these related processes as one entity, and when a user issues the appropriate key combination (usually ), the entire group of processes gets suspended.
Jobs are managed by the operating system as a single process group, and the job is the shell's internal representation of such a group. This is defined in POSIX as:
A job can be referred to by a handle called the "job control job ID" or simply "", which is used by shell builtins to refer to the job. Job IDs begin with the codice_1 character; codice_2 identifies job "n", while codice_3 identifies the current job. Other job IDs are specified by POSIX. In informal usage the number may be referred to as the "job number" or "job ID", and Bash documentation refers to the (%-prefixed) job ID as the "jobspec."
Job control and job IDs are typically only used in interactive use, where they simplify referring to process groups; in scripting PGIDs are used instead, as they are more precise and robust, and indeed job control is disabled by default in bash scripts.
History.
Job control was first implemented in the C shell by Jim Kulp, then at IIASA in Austria, making use of features of the 4.1BSD kernel.
The KornShell, developed at Bell Labs, adopted it and it was later incorporated into the SVR4 version of the Bourne shell, and exists in most modern Unix shells.
Commands.
The POSIX standard specifies two commands for resuming suspended jobs in the background and foreground, respectively and . These were modeled after the Korn shell job control commands.
Implementation.
Typically, the shell keeps a list of jobs in a job table. Recall that a job corresponds to a process group, which consists of all the members of a pipeline and their descendants. The codice_4 command will list the background jobs existing in the job table, along with their job number and job state (stopped or running). When a session ends when the user logs out (exits the shell, which terminates the "session leader" process), the shell process sends SIGHUP to all jobs, and waits for the process groups to end before terminating itself.
The codice_5 command can be used to remove jobs from the job table, so that when the session ends the child process groups are not sent SIGHUP, nor does the shell wait for them to terminate. They thus become orphan processes, and may be terminated by the operating system, though more often this is used so the processes are adopted by init (the kernel sets their parent process to init) and continue executing as daemons. Alternatives to prevent jobs from being terminated include nohup and using a terminal multiplexer.
A job running in the foreground can be stopped by typing the suspend character (Ctrl-Z). This sends the "terminal stop" signal (SIGTSTP) to the process group. By default, SIGTSTP causes processes receiving it to stop, and control is returned to the shell. However, a process can register a signal handler for or ignore SIGTSTP. A process can also be paused with the "stop" signal (SIGSTOP), which cannot be caught or ignored.
A job running in the foreground can be interrupted by typing the interruption character (Ctrl-C). This sends the "interrupt" signal (SIGINT), which defaults to terminating the process, though it can be overridden.
A stopped job can be resumed as a background job with the codice_6 builtin, or as the foreground job with codice_7. In either case, the shell redirects I/O appropriately, and sends the SIGCONT signal to the process, which causes the operating system to resume its execution. In Bash, a program can be started as a background job by appending an ampersand (codice_8) to the command line; its output is directed to the terminal (potentially interleaved with other programs' output), but it cannot read from the terminal input.
A background process that attempts to read from or write to its controlling terminal is sent a SIGTTIN (for input) or SIGTTOU (for output) signal. These signals stop the process by default, but they may also be handled in other ways. Shells often override the default stop action of SIGTTOU so that background processes deliver their output to the controlling terminal by default.
In Bash-compatible shells, the codice_9 builtin (not codice_10) can signal jobs by job ID as well as by process group ID – sending a signal to a job sends it to the whole process group, and jobs specified by a job ID should be killed by prefixing codice_1. codice_9 can send any signal to a job; however, if the intent is to rid the system of the processes the signals SIGKILL and SIGTERM (the default) are probably the most applicable.


Mega Man Legends (video game)

Mega Man Legends is an action-adventure shooter game released by Capcom. It is the first game in the "Mega Man Legends" sub-series of "Mega Man" games from Capcom, and the second major 3D polygonal "Mega Man" title released in the franchise, following "". It was released on the PlayStation in 1997 in Japan and in 1998 in North America. A Nintendo 64 port was released in 2000 with the same title, but it was renamed Mega Man 64 for the English release in 2001. Another port was released for Microsoft Windows in 2001 and the PlayStation Portable in 2005, with the latter only in Japan. It was rereleased for the PlayStation 3 only in the United States in 2015.
While set in the far distant future of the same universe as the original and "X" series' that premiered before it, "Legends" stars a different spiritual incarnation of Mega Man named Mega Man Volnutt, the game's player character. Mega Man Volnutt is a "Digger", a person in charge of investigating ruins from a flooded Earth. During his journey with his friends, their ship crashes in Kattelox Island, where Mega Man confronts pirates who are attacking it to obtain its hidden treasure. As an action-adventure game, "Mega Man Legends"s gameplay is vastly different from that of the original series, despite sharing a few elements.
"Mega Man Legends" received positive critical response due to the series' jump from 2D graphics to 3D. Ports for the Nintendo 64 and Windows received negative comments for lacking updates from the PlayStation version, whose graphics were considered outdated by the time the ports were released. "Mega Man Legends" was followed by the prequel "The Misadventures of Tron Bonne" and a sequel titled "Mega Man Legends 2".
Gameplay.
"Mega Man Legends" differs greatly from the platforming gameplay of past "Mega Man" games, the main factor being the three-dimensional worlds, and three-dimensional movement therein. Unlike the original "Mega Man" series which are platform games, "Legends" is an action-adventure game with elements from "Tomb Raider" like the ability to grab onto and climb up ledges, a left/right dive maneuver, manual camera control, and lock-on targeting, the last of which was also featured in games such as "". The player controls Mega Man Volnutt across the title, in which he has to complete different missions such as investigating ruins or fighting pirates. The player travels through a large world, with various dungeons that are explored in a certain order, as well as a town with non-player characters to talk to. The plot is revealed through cutscenes.
Although the only way to move in the game is on foot, once Roll Caskett repairs a support car, she is able to directly take Mega Man to specific areas. In "Legends", large gems called Refractors are used as a power source. Small shards of them can be exchanged for money, and in the game, enemies that are destroyed will often drop these Refractor Shards. When shards are picked up, the equivalent amount of Zenny, the game's basic unit of currency, is added automatically. The health of Mega Man can be increased through the game in the shops, while it can be recovered through packs bought at shops, obtaining red spheres from defeated opponents or by asking the character Data to recover Mega Man's health. Mega Man also has a Life Shield which reduces the damage that he can receive from enemies. The damage caused by enemies can also be reduced by obtaining upgrades to Mega Man's armor or his helmet. Mega Man's interactions with characters from the game can also affect the price of objects. If the player makes Mega Man be rude with characters, prices from objects will be increased and the dialogues with people will also change.
The power of Mega Man's main weapon, the Buster Gun, depends on the Buster Parts equipped. Buster Parts can be equipped to upgrade four stats of the Buster Gun; Attack (how strong it is), Rapid (how fast it fires), Range (how far the shots go), and Energy (how many shots can be fired before pausing). Buster Parts can be retrieved from stores or from dungeons. Additionally, Roll is able to create Buster Parts from unusable objects found in the ruins. Roll is also able to make weapons for the player, using specific combinations of parts that can be found in dungeons or bought in shops. Many of these weapons supplement the Buster Gun. The only way to refill them in the field is an item that can be bought, but only one can be carried. Only one special weapon can be equipped at a time, and the only way to switch is to talk to Roll, unlike the original series. Special weapons can be upgraded, and have five stats; Attack, Rapid, Range, Energy, and Special. In order to upgrade them, the player must pay a specific amount of Zenny.
Plot.
Setting and characters.
The "Legends" series takes place on a flooded Earth. Because of the flooding, only a few sparse islands exist and energy sources are rare. In order to satisfy this increasing demand for energy to power up machinery, quantum refractors found in ancient ruins are used. These refractors are valuable; they serve as an energy source, and their shards are used as currency. However, the main goal of every person is to find the Mother Lode, an item of supposed infinite power that can fill the need for the energy in one swoop. Those who try to excavate these ruins are called "Diggers" ("Digouters" in the Japanese version). The protagonist of the game is Mega Man Volnutt, a Digger living in a ship called Flutter. He lives there alongside Roll Caskett, his Spotter who is searching for her missing father, Barrel Caskett, Roll's grandfather, and Data, a mysterious monkey that talks in gibberish only Mega Man himself can understand. The game's antagonists are pirates known as the Bonnes who want to steal Kattelox's secret treasure in order to become rich. They consist of Teisel Bonne, the leader of the group. His sibling is Tron Bonne, who builds most of their robots used in their elaborate schemes (and develops feelings for Mega Man), and the youngest brother, Bon Bonne, who can only say one word—"Babu!" The Bonnes are accompanied by forty Servbots, robots under the care of Tron. They live and travel in their flying warship, the Gesellschaft.
Story.
Mega Man Volnutt exits a ruin after finding the refractor inside. After dealing with the Reaverbots blocking his way out, he makes his way to the Flutter, which leaves the ruin. However, the Flutter experiences some engine problems and crash lands on Kattelox Island. From there, the Casketts try to find a way to repair their ship. However, when the pirates the Bonnes attack Kattelox's city with giant mechanical weapons, Mega Man decides to stop them. Once Mega Man defeats the Bonnes, Kattelox's mayor, Amelia, tells Mega Man the Bonnes are searching for the island's secret treasure and that it is said if somebody obtains it, a great disaster will befall the island. Amelia asks Mega Man to investigate the island's ruins. With a refractor found in a ruin, Roll and Mega Man repair the Flutter, allowing them to find a cave to continue exploring the island. While exploring the cave, Mega Man activates the Main Gate, a dungeon where he should be able to find the reason why Reaverbots from the island are being activated. Mega Man confronts the Bonnes who, after being defeated once again, decide to let Mega Man enter the Main Gate, planning to steal the treasure from him afterward.
When Mega Man explores the depths of the Main Gate, he discovers it is actually a stasis chamber for the ancient robot Mega Man Juno, a 3rd class bureaucratic unit from Eden, a space station orbiting above the planet. When he is accidentally awakened from his sleep by Mega Man, Juno refers to Mega Man as "Mega Man Trigger", and realizes that Mega Man is suffering from memory loss. Juno claims that the island's population needs to be purged so it will be more controllable, and confronts Mega Man when he tries to stop him. After a struggle, Juno is defeated and dies. Even with Juno's physical body gone, he transfers his backup data into the systems of Eden, preventing the halt of the Carbon Purification Process. Data gives new commands to the system, stopping the Purification and deleting Juno's backup data from Eden. Data then reveals to Mega Man that he contains all of his previous memories from when he was Mega Man Trigger. Mega Man had stored his memories into Data as a way to prevent Eden from ever tampering with it. Data promises to restore Mega Man's memory when the time comes. The residents proclaim Mega Man a hero and the Caskett family rides off in the repaired Flutter to continue their journey. The Bonnes sail on a vessel built by Tron out of the scraps from the Gesellschaft, with the giant refractor from the main gate and Bon Bonne in tow.
Development and release.
Producer Keiji Inafune stated his purpose was to create a new "Mega Man" which would be completely different from all the others. Wanting that game to entertain gamers of all ages, Inafune decided to mix the action, RPG and adventure genres but wondered whether "Mega Man Legends" would still be entertaining. The humanoid characters in the game were all animated with motion capture. One of the earliest showings of "Legends" around the world took place at the Electronic Entertainment Expo in Atlanta, Georgia on June 1997 under the title "Mega Man Neo". A demo of the game, titled "" would later be included in the Japanese director's cut version of "Resident Evil". The game was released in Japan on December 18, 1997, while a re-release with the label of "PlayStation the Best" was published on May 4, 1999.
In December 1997, Capcom USA's president, Bill Gardner, told IGN that "Mega Man Legends" would be ported to the Nintendo 64. Despite the final Japanese name being already finalized, "Mega Man Neo" remained as an English name, with Gardner stating the title was not decided. In January 1998 the game was renamed "Mega Man Nova" as the general consensus did not find the previous name appealing, only to revert it back just two weeks later due to arising potential trademark issues. The title "Mega Man Legends" was decided and confirmed in March 1998. By April 1998, the English adaptation of the game was finished, but Capcom decided to delay its release until September of the same year, believing it would fit better during the holiday seasons. The English localization removed an option from the original game in which Mega Man protects Tron from a dog chasing her; while in the Japanese version, Mega Man could either kick or calm the dog, in the English release he could only calm to the dog. Other changes to the English version were the names of characters, such as the protagonist Mega Man Volnutt, whose Japanese name is Rock Volnutt.
The PC port of the game was first announced by Capcom at the Tokyo Game Show in April 2000 alongside "Dino Crisis" and "". The PlayStation Portable version of "Mega Man Legends" was released in Japan on August 4, 2005. It was re-released on December 21, 2006 and January 29, 2009, with the latter also including the PSP port of "Mega Man Legends 2". Although a North American release of the port was planned, it was cancelled.
The soundtrack was composed by Makoto Tomozawa. The sound designers found it a challenge to make the sounds for the game, with one of them, Toshio Kajino, having never worked on a "Mega Man" title. The theme for the Japanese version of the game is "Another Sun" and the ending theme is , both by Reika Morishita. On February 21, 1998, Capcom published a CD of the game called . It contains a total of 40 tracks including the opening and ending themes. Tomozawa notes that the CD still lacks other tracks from the game due to the large number of tracks it had.
Reception.
Since its release, "Mega Man Legends" has received moderately positive critical response from video game publications although the ports for Nintendo 64 and PC received from mixed to negative comments. GameRankings had an average of 73.73% for the PS version. The PC and Nintendo 64 version had lower averages of 33.67% and 63.94%, respectively. On Metacritic, the Nintendo 64 port holds an aggregate 59 out of 100 based on six reviews The jump from a 2D platform video game series to a 3D action-adventure game was well received, as reviewers compared it with other video game franchises whose changes were overall negative. Despite the change, critics liked how "Legends" shares various elements from the original "Mega Man" series. "Game Informer" liked the variations of Mega Man's special weapons as "There is plenty of shoot-em-up action for fans of traditional Mega Man titles." The storyline of the game was also praised, being labelled as "solid" by "Game Informer" and "engrossing" by "GamePro", the latter praising the bosses characters as one of the best ones from the whole series. On the other hand, the game's difficulty received mixed reviews with focus on the boss battles, but praise in the addition of a tutorial mode later added to the Nintendo 64 port.
"Next Generation" reviewed the PlayStation version of the game, rating it three stars out of five, and stated that "first impressions can be a killer, and the game just doesn't possess the most outstanding graphics or mechanics to hook the merely curious after just one play. For those who look deeper, it's a diamond in the rough."
The N64 port, however, received criticism by "Famitsu" for being too similar to the original game. IGN commented that the PlayStation game "was a poor experience", asking "why Capcom [...] decided to make Nintendo 64 owners suffer through it unchanged". GameSpot thought that the graphics were outdated and that apart from not having any update from the original game, some music and sound clips were lost during conversion. The PC version received a more negative review; GameSpot gave it a "bad" 3.6 out of 10 stating gamers would find the PlayStation port more worthwhile. Similarly to "Famitsu"s review of the Nintendo 64 port, GameSpot complained about the lack of additions to the PC port. The PC's conversions of the cutscenes during the game were found to have a mistake which makes a character start a dialogue while another one is still talking.
In a 2007 retrospective of the "Mega Man" series, Jeremy Parish of 1UP.com ranked "Mega Man Legends" as "Worth it!", with praise focused on the setting, the plot, the English voice acting and the boss battles. GamesRadar shared similar opinions, stating "it was a complete overhaul in every way" and noting that its jump to 3D graphics "seems totally lost in this day and age..." On the other hand, ScrewAttack placed "Mega Man Legends" fourth in their article, "Top Ten Worst 2D to 3D Games", with criticism focused in the game controls, the camera, and the main character's voice. "Allgame" mentioned that while the game "had some significant problems that kept it from being anything more than a diversion" with its most notable one being the controls which were improved in the sequel. Mega Man's design was third in "GamePro"s "The 8 Worst Game Character Makeovers Ever" in which the author Patrick Shaw commented that having Mega Man without a helmet "just doesn't work". GamesRadar's article "Gaming's most absurdly oversized limbs" featured the game as an example of games with characters' oversized arms. In 2008, Joystiq's Wesley Fenlon listed "Mega Man Legends" as a potential game to be ported for the Wii with comments focused in the game's and the console's controls. In December 1998, a Capcom representative stated that "Mega Man Legends" became a very popular game.
Inafune stated that the game did not sell well, which he attributed to it being released years before sandbox games came into vogue.


PlayStation 2 accessories

Various accessories for the PlayStation 2 video game console have been produced by Sony, as well as third parties. These include controllers, audio and video input devices like microphones and video cameras, and cables for better sound and picture quality.
Game controllers.
DualShock 2.
The DualShock 2 Analog Controller (SCPH-10010) is the standard controller for the PlayStation 2 and is almost identical to the original DualShock controller for the original PlayStation console with only minor changes. All the buttons other than L3, R3 and "Analog" feature analog pressure sensitivity; the connecting cable is slightly longer than the original DualShock and is black rather than grey; the connector is squarer; DualShock 2 is printed on the top of the controller and it features two more levels of vibration feedback.
Logitech Cordless Action controller.
The Logitech Cordless Action controller is an officially licensed wireless controller for the PlayStation 2 made by Logitech. It features all of the inputs found the standard DualShock 2 controller, i.e. ten analog (pressure-sensitive) buttons (, , , , L1, R1, L2, R2, Start and Select), three digital buttons (L3, R3 and the analog mode button) and two analog sticks. As its buttons are pressure-sensitive, the controller is compatible with games which require a DualShock 2. The controller also features two vibration motors for haptic feedback, which are compatible with DualShock/DualShock 2 enabled games. As a power saving measure, the vibration may be turned on or off by the user by way of a button on the controller's face. It is powered by two AA batteries. It communicates with the console using a proprietary 2.4 GHz RF protocol wireless by way of a dongle which connects to the PS2's controller port in a similar manner to Nintendo's WaveBird wireless controller.
Logitech Cordless Controller.
Like the Logitech Cordless Action controller, the Logitech Cordless Controller is an officially licensed wireless PlayStation 2 controller made by Logitech. It features all of the buttons (including analog functionality) of the standard DualShock 2 controller and is compatible with games requiring a DualShock 2. It is powered by two AA batteries, and as a power-saving measure, the vibration function can be turned off. It communicates with the console via a wireless dongle which connects to the PS2's controller port and uses a proprietary 2.4 GHz RF technology.
Sega Saturn PS2 Controller.
The Sega Saturn PS2 Controller is a controller for the PS2 based around the Sega Saturn type-2/Japanese style controller. The controller is officially licensed by both Sony and Sega, and the first version was released in black exclusively in Japan in 2005. A second version was produced in the color purple as part of a joint venture between Sega and Capcom to coincide with the launch of Vampire: Darkstalkers Collection in Japan. Other than the connector, it is almost identical to the original Saturn controller, with a few minor changes. In place of the original Saturn "start" button are indented PlayStation style "start" and "select" buttons. Additionally, the "reset", "stop", "play/pause", "rewind" and "fast-forward" labels above the X, Y, Z, L and R buttons have been removed, and labels of the corresponding PlayStation buttons have been added as listed below.
Logitech Driving Force GT.
http://uk.playstation.com/ps2/peripherals/detail/item285752/Driving-Force%E2%84%A2-GT/
Rhythm Game Controllers.
Microphones.
Various microphones are available for use on the PlayStation 2 with rhythm games such as Sony's own Singstar karaoke games and Harmonix's Rock Band series. Singstar microphones are available in both wired and wireless varieties; both connect to the console via USB.
Dance Mats/Pads.
On certain PS2 Games that are dance pad compatible allows the player to follow alongside on the game actions as the player must perform, they are usually found on games such as, Dance Revolution games.
Buzz! Buzzers.
Buzz! Buzzers are special controllers designed specifically for the "Buzz!" quiz game series. The controllers feature large red buzzer buttons and four smaller coloured buttons for answer selection. Both wired and wireless versions are available and come bundled with "Buzz!" games. A four-buzzer set acts as a single USB device and connects a USB port on the PlayStation 2. Wireless versions connect via a USB dongle, with each dongle able to support up to 4 wireless buzzers at a time. A second dongle is required for additional buzzers (for 8 player games). Both the wired and wireless versions of the buzzers are compatible with both PlayStation 2 and PlayStation 3. The "big button controllers" available for the Xbox 360 heavily resemble buzzers in many respects, and fulfil the same function.
DVD Remote Control.
The DVD remote control is an infra-red remote control for the PlayStation 2 designed to allow easier control of DVD movies. The first remote SCPH-10150 came bundled (as SCPH-10170) with an infra-red receiver dongle SCPH-10160 which attached to one of the PlayStation 2's controller ports; this dongle is not needed on later PS2 models (beginning from SCPH-500xx) and slimline PS2 models (SCPH-700xx to SCPH-900xx) as they feature an integrated IR port.
There are two different models of the DVD remote control released, which only had minor differences. The first released is the SCPH-10150. The second, SCPH-10420, is functionally and visually identical apart from the addition of eject and reset/power buttons. However the eject button will only work on PS2 models SCPH-100xx to -500xx, as the slimline PlayStation 2 models had no motorized disc tray to eject.
Both versions of the remote feature all the standard PS2 buttons in addition to DVD playback controls.
A/V Cables.
Various A/V cables have been made available for the PlayStation 2, which offer varying levels of picture quality. Additionally, the PS2 features a TOSLINK port, which facilitates the output of digital S/PDIF audio - 2-channel LPCM, 5.1-channel Dolby Digital and 5.1-channel DTS (the latter two are only available during DVD playback when it is encoded on the disk). The PS2 is compatible with all PlayStation and PlayStation 3 cables which use the AV-multi port.
RFU adapter.
The RFU Adapter (SCPH-1122) is an RF Modulator and cable that carries mono audio and video at 576i/50 Hz (PAL) or 480i/60 Hz (NTSC) via an RF signal and connects using a TV aerial plug. It is similar to the RFU adapter cable available for the PlayStation.
AV (Composite) cable.
The AV cable (SCPH-10500) is included with the PS2 and carries dual-channel (stereo) audio and composite video at 576i/50 Hz (PAL) or 480i/60 Hz (NTSC). It is identical to the composite cables available for the PlayStation and PlayStation 3. Consoles in PAL territories also come bundled with a composite/stereo SCART adapter block to facilitate connection to SCART enabled TVs. This is merely an adapter and provides no quality improvement over a direct composite connection.
S-Video Cable.
The S-Video cable (SCPH-10060U/97030) carries dual-channel (stereo) audio and s-video at 576i/50 Hz (PAL) or 480i/60 Hz (NTSC), which provides a clearer picture than the standard AV cable.
AV Adaptor.
The AV Adaptor with S Video Out Connector (SCPH-10130) is a break-out box which provides an additional AV-Multi out port, as well as composite, s-video and stereo audio connectors to allow connection to an AV receiver or similar device.
EURO AV (RGB SCART) cable.
The EURO AV Cable (SCPH-10142) is a SCART cable capable of carrying 576i/50 Hz or 480i/60 Hz using the RGB standard, as well as standard stereo audio and composite video. It provides a clearer picture than either s-video or composite signals. The Euro AV Cable can also carry 480p and 1080i signals, but to do so it switches off RGBs (RGB Sync) signals and switches to RGsB (RGB sync on green). This can lead to compatibility issues with certain monitors and even SCART to HDMI upscalers. To use the EURO AV cable, the PS2 must be set to RGB mode in the options.
Component AV cable.
The Component AV Cable (SCPH-10490) is a cable capable of carrying 576i/50 Hz or 480i/60 Hz using the YPBPR and RGB standards, as well as standard stereo audio, via RCA connectors. It provides a clearer picture than either s-video or composite signals. It is also required for games which support other video modes such as "progressive scan" (480p) or 1080i. Most PS1 games output at 240p through the cable, which may cause compatibility issues with some newer TV's. To use the Component AV cable, the PS2 must be set to YPBPR mode in the options.
D-Terminal cable.
The D-Terminal cable is identical to the component cable other than its connector. It was sold only in Japan and uses the Japanese D-Terminal standard.
VGA Cable.
The PlayStation 2 VGA cable carries RGBHV video via a VGA connector. It is only compatible with progressive scan games and PS2 Linux. Since the PS2 does not output separate sync, sync on green must be used instead, which may be incompatible with some monitors.
Other accessories.
Memory Card.
The Memory Card (8 MB) (SCPH-10020) Magic Gate is used to store settings, EyeToy video messages and savegames. Official Sony memory cards are only available at a size of 8 MB, the memory card came in black, crimson red, and ocean blue.
Later, Sony partnered with a third-party accessories company Katana to make Memory Cards that came in 16 MB and 32 MB. These Memory Cards were officially licensed products and has the PlayStation 2 logo, and says Magic Gate on them.
Third party memory cards are available up to 128 MB.
The Memory Card (8 MB) is the earliest known commercial product to use ferroelectric RAM (FeRAM). The Memory Card's microcontroller (MCU) contains 32kb (4kB) embedded FeRAM manufactured by Toshiba. It was fabricated using a 500 nm complementary metal-oxide-semiconductor (CMOS) process.
Multitap.
The Multitap for PlayStation 2 allows up to four controllers and four memory cards to be attached to a single controller port and memory card slot. Up to 8 controllers and memory cards may be attached to the console at any one time by using two multitaps simultaneously. Certain Multitaps will not work with specific PS2 models due to slight differences in slot placement. SCPH-10090 was designed to fit the original consoles, while SCPH-70120 was instead designed for the slim consoles.
EyeToy.
The EyeToy is a digital camera device, similar to a webcam, for the PlayStation 2. Originally, EyeToys were manufactured by Logitech (known as "Logicool" in Japan), while later models were manufactured by Namtai. The EyeToy is mainly used for playing specifically-designed EyeToy games, but can also be used to capture images and videos. It is also compatible with the PlayStation 3.
Headset.
The PS2 headset connects via USB 1.1 on the front of the console. The headset is most commonly used in online multiplayer games; however, it can also be used in some karaoke style games, for voice control, and to enhance the immersive experience of some single player games.
Headphone Splitter.
3.5mm Audio Stereo Y Splitter can transfer audio from PlayStation to 2 output devices including headphones, headset, speakers and more
Network Adapter.
The PlayStation 2 network adapter is an optional accessory for some internet multiplayer compatible games. Although the PS2 Slim had one built in, the PS2 fat network adapter needed to be purchased.
Keyboard and Mouse.
An official Sony PlayStation 2 USB keyboard and mouse came bundled as part of Linux for PlayStation 2 which turns any non slim PS2 into a Linux computer. Any standard USB keyboard and mouse will work. In addition to the Linux kit, there were a handful of games that used a keyboard and mouse or just a mouse or trackball.
Vertical Stand.
The Vertical Stand is attached to the PlayStation 2 console to allow it to stand vertically. Three different versions are available: SCPH-10040 for original (large) consoles, SCPH-70110 for slimline SCPH-700xx consoles and SCPH-90110 for slimline SCPH-900xx consoles.
Horizontal Stand.
The horizontal stand is attached to the base of original "fat" PlayStation 2 consoles to add height, and style.


MMX (instruction set)

MMX is a "single instruction, multiple data" (SIMD) instruction set architecture designed by Intel, introduced on January 8, 1997 with its Pentium P5 (microarchitecture) based line of microprocessors, named "Pentium with MMX Technology". It developed out of a similar unit introduced on the Intel i860, and earlier the Intel i750 video pixel processor. MMX is a processor supplementary capability that is supported on IA-32 processors by Intel and other vendors .
The New York Times described the initial push, including Super Bowl advertisements, as focused on "a new generation of glitzy multimedia products, including videophones and 3-D video games."
MMX has subsequently been extended by several programs by Intel and others: 3DNow!, Streaming SIMD Extensions (SSE), and ongoing revisions of Advanced Vector Extensions (AVX).
Overview.
Naming.
MMX is officially a meaningless initialism trademarked by Intel; unofficially, the initials have been variously explained as standing for
Advanced Micro Devices (AMD), during one of its many court battles with Intel, produced marketing material from Intel indicating that MMX stood for "Matrix Math Extensions". Since an initialism cannot be trademarked, this was an attempt to invalidate Intel's trademark. In 1995, Intel filed suit against AMD and Cyrix Corp. for misuse of its trademark MMX. AMD and Intel settled, with AMD acknowledging MMX as a trademark owned by Intel, and with Intel granting AMD rights to use the MMX trademark as a technology name, but not a processor name.
Technical details.
MMX defines eight processor registers, named MM0 through MM7, and operations that operate on them. Each register is 64 bits wide and can be used to hold either 64-bit integers, or multiple smaller integers in a "packed" format: one instruction can then be applied to two 32-bit integers, four 16-bit integers, or eight 8-bit integers at once.
MMX provides only integer operations. When originally developed, for the Intel i860, the use of integer math made sense (both 2D and 3D calculations required it), but as graphics cards that did much of this became common, integer SIMD in the CPU became somewhat redundant for graphical applications. Alternatively, the saturation arithmetic operations in MMX could significantly speed up some digital signal processing applications.
To avoid compatibility problems with the context switch mechanisms in existing operating systems, the MMX registers are aliases for the existing x87 floating-point unit (FPU) registers, which context switches would already save and restore. Unlike the x87 registers, which behave like a stack, the MMX registers are each directly addressable (random access).
Any operation involving the floating-point stack might also affect the MMX registers and vice versa, so this aliasing makes it difficult to work with floating-point and SIMD operations in the same program. To maximize performance, software often used the processor exclusively in one mode or the other, deferring the relatively slow switch between them as long as possible.
Each 64-bit MMX register corresponds to the mantissa part of an 80-bit x87 register. The upper 16 bits of the x87 registers thus go unused in MMX, and these bits are all set to ones, making them "Not a Number" (NaN) data types, or infinities in the floating-point representation. This can be used by software to decide whether a given register's content is intended as floating-point or SIMD data.
Software support.
Software support for MMX developed slowly. Intel's C Compiler and related development tools obtained intrinsics for invoking MMX instructions and Intel released libraries of common vectorized algorithms using MMX. Both Intel and Metrowerks attempted automatic vectorization in their compilers, but the operations in the C programming language mapped poorly onto the MMX instruction set and custom algorithms as of 2000 typically still had to be written in assembly language.
Successors.
AMD, a competing x86 microprocessor vendor, enhanced Intel's MMX with their own 3DNow! instruction set. 3DNow is best known for adding single-precision (32-bit) floating-point support to the SIMD instruction-set, among other integer and more general enhancements.
Following MMX, Intel's next major x86 extension was the Streaming SIMD Extensions (SSE), introduced with the Pentium III family in 1999, roughly a year after AMD's 3DNow! was introduced.
SSE addressed the core shortcomings of MMX (inability to mix integer-SIMD ops with any floating-point ops) by creating a new 128-bit wide register file (XMM0–XMM7) and new SIMD instructions for it. Like 3DNow!, SSE focused exclusively on single-precision floating-point operations (32-bit); integer SIMD operations were still performed using the MMX register and instruction set. However, the new XMM register-file allowed SSE SIMD-operations to be freely mixed with either MMX or x87 FPU ops.
"Streaming SIMD Extensions 2" (SSE2), introduced with the Pentium 4, further extended the x86 SIMD instruction set with integer (8/16/32 bit) and double-precision floating-point data support for the XMM register file. SSE2 also allowed the MMX "operation codes" (opcodes) to use XMM register operands, extended to even wider YMM and ZMM registers by later SSE revisions.
MMX in embedded applications.
Intel's and Marvell Technology Group's XScale microprocessor core starting with PXA270 include an SIMD instruction set architecture extension to the ARM architecture core named "Intel Wireless MMX Technology" (iwMMXt) which functions are similar to those of the IA-32 MMX extension. It provides arithmetic and logic operations on 64-bit integer numbers, in which the software may choose to instead perform two 32-bit, four 16-bit or eight 8-bit operations in one instruction. The extension contains 16 data registers of 64-bits and eight control registers of 32-bits. All registers are accessed through standard ARM architecture coprocessor mapping mechanism. iwMMXt occupies coprocessors 0 and 1 space, and some of its opcodes clash with the opcodes of the earlier floating-point extension, FPA.
Later versions of Marvell's ARM processors support both "Wireless MMX" (WMMX) and "Wireless MMX2" (WMMX2) opcodes.


Jurix

Jurix was an early GNU/Linux distribution created by Florian La Roche, a former employee of the legal department at Saarland University. The distribution was maintained between 1993 and 1999 and hosted on the now-defunct "jurix.jura.uni-sb.de" and "susix.jura.uni-sb.de" domains.
In 1996, jurix superseded Slackware as a base for SuSE Linux.
The name "jurix" was borrowed from the department's first HTTP server, named by Alexander Sigel. It is not known whether the name was taken from the nearby Dutch law and IT organisation JURIX, or simply a portmanteau of "Jura" (meaning "law" in German) and "Unix".
A readme from 1999 touts the following software, among others:


LOGOW.SYS


SMARTDRV.SYS


INTERLNK.EXE


CatOS


OASIS operating system


Solbourne Computer

Solbourne Computer Inc. was originally a vendor of computer systems based in Longmont, Colorado, United States, at first 52% owned by Matsushita. In the late 1980s and early 1990s, the company produced a range of computer workstations and servers based on the SPARC microprocessor architecture, largely compatible with Sun Microsystems' Sun-4 systems. Some of these are notable for supporting symmetric multiprocessing some time before Sun themselves produced multiprocessor systems. Even when Sun produced multiprocessor systems, SunOS uses an asymmetric multiprocessing model rather than OS/MP's symmetric multiprocessing model; Sun would not adopt symmetric multiprocessing until the release of Solaris 2.0 in 1992. Due to the cost of engineering and producing new systems to compete with Sun's increasingly competitive hardware offerings and the loss of symmetric multiprocessing as a distinguishing feature, in 1994, Solbourne left the computer hardware business, with Grumman Systems Support Corporation taking over support for Solbourne customers until 2000.
In 1994, Walt Pounds assumed the role of CEO of Solbourne, and the Solbourne headquarters were moved to Boulder, Colorado. From that point until July 2008, Solbourne focused on providing consulting services and solutions based on Oracle Applications and associated technologies. Solbourne established a strong reputation in the Oracle E-Business Suite community, and has become a dominant provider of consulting services to state and local Oracle E-Business Suite customers.
On July 11, 2008, Solbourne closed a transaction to sell substantially all of the company assets to Deloitte Consulting. The Solbourne management team and more than 100 professionals joined Deloitte’s Enterprise Applications, Technology Integration and Human Capital service areas.
Models.
Solbourne's range comprises the following:
Operating systems.
All Solbourne systems run OS/MP, a modified version of SunOS 4.1 supporting multiprocessor systems. The final release of OS/MP was 4.1D, corresponding to SunOS 4.1.3.
, some work has been done in porting OpenBSD to Solbourne IDT workstations.


IOPL


List of AMD FX microprocessors

AMD FX is a series of AMD microprocessors for personal computers. The following is a list of AMD FX brand microprocessors. Some APUs also carry an FX model name, but the term "FX" normally only refers to CPUs which are not just APUs with the iGPU disabled.
Desktop "pure" CPUs.
Athlon 64 Family (90–130 nm).
These processors were the first AMD CPUs to use the "FX" designation and identified the chip as being higher-performance. The frequency multiplier was unlocked in these chips. See the comprehensive List of AMD Athlon 64 microprocessors
SledgeHammer Core (130 nm).
Instruction sets: MMX, SSE, SSE2, Enhanced 3DNow!, NX bit, AMD64
Socket 940
FX-51 (2.2 GHz) and FX-53 (2.4 GHz)
ClawHammer Core (130 nm).
Instruction sets: MMX, SSE, SSE2, Enhanced 3DNow!, NX bit, AMD64
Socket 939
FX-53 (2.4 GHz) and FX-55 (2.6 GHz)
SanDiego Core (90 nm).
Instruction sets: MMX, SSE, SSE2, SSE3, Enhanced 3DNow!, NX bit, AMD64, Cool'n'Quiet
Socket 939
FX-55 (2.6 GHz) and FX-57 (2.8 GHz)
Toledo Core (90 nm, dual-core).
Instruction sets: MMX, SSE, SSE2, SSE3, Enhanced 3DNow!, NX bit, AMD64, Cool'n'Quiet
Socket 939
FX-60 (2.6 GHz)
Windsor Core (90 nm, dual-core).
Instruction sets: MMX, SSE, SSE2, SSE3, Enhanced 3DNow!, NX bit, AMD64, Cool'n'Quiet, AMD-V
Socket AM2
FX-62 (2.8 GHz)
Windsor Core (90 nm, dual-core, dual-processor).
Instruction sets: MMX, SSE, SSE2, SSE3, Enhanced 3DNow!, NX bit, AMD64, Cool'n'Quiet, AMD-V
Socket F
FX-70 (2.6 GHz), FX-72 (2.8 GHz), FX-74 (3.0 GHz)
Bulldozer Family (32 nm).
Bulldozer Core (Zambezi, 32 nm).
"Zambezi" (32 nm SOI)
Piledriver Core (Vishera, 32 nm).
"Vishera" (32 nm SOI)


Wendy Schmidt

Wendy Schmidt (born Wendy Susan Boyle; 1955) is an American businesswoman and philanthropist. She is the wife of Eric Schmidt, the former CEO of Google, whom she met in graduate school at the University of California, Berkeley.
She is the president of the Schmidt Family Foundation, holding over $1 billion in philanthropic assets.
Biography.
She was born in 1955 in Orange, New Jersey. Her parents owned an interior design firm, Boyle Design Associates.
She graduated from Smith College in 1977 and attended graduate school at the University of California, Berkeley. While there, she met Eric Schmidt, then a doctoral student in computer science, and edited his thesis. They married in June 1980.
After graduating in 1981 with a master's degree in journalism, she joined the marketing department of Sun Microsystems, where Eric Schmidt later worked as well. She left Sun in 1986 to start an interior design firm, which she ran for 16 years. Wendy and Eric Schmidt have two daughters, Sophie and Alison. Alison died in 2017 from an illness.
Philanthropy.
In 2005, Schmidt became a trustee of the Natural Resources Defense Council (NRDC) and founded the 11th Hour Project to raise awareness about climate change and global warming.
In 2006, Wendy and Eric Schmidt established the Schmidt Family Foundation to address issues of sustainability and the responsible use of natural resources. She is the president of the foundation and directs its grant making. As a yachtswoman, Schmidt has taken a personal interest in promoting some of the 11th Hour Project's ocean awareness programs through competitive sailing.
After the establishment of the foundation, The 11th Hour Project became its main direct charitable program. ReMain Nantucket, founded in 2007 by Wendy Schmidt, is a program area of The Schmidt Family Foundation focused on the economic, social, and environmental vitality of downtown Nantucket, Massachusetts.
In 2009, Wendy and Eric Schmidt created the $25 million Schmidt Transformative Technology Fund at Princeton University to support research and technology in the natural sciences and engineering. The Fund awarded $1.2 million in grants in 2010 and $1.7 million in grants in 2012.
In 2010, through the Schmidt Family Foundation, she offered the prize purse of the Wendy Schmidt Oil Cleanup X Challenge, a challenge award for the efficient capturing of crude oil from seawater motivated by the Deepwater Horizon oil spill.
Schmidt has supported propositions and politicians in California. She gave $1 million to Proposition 87, a failed 2006 initiative to raise taxes on oil companies to pay for research and incentives to support alternative energy; $50,000 to the Prevention of Farm Animal Cruelty Act, which was approved by voters; and $25,900 to Jerry Brown’s successful campaign for Governor of California.
She serves on the boards of the California Academy of Sciences, Climate Central, the X Prize Foundation, the Cradle to Cradle Products Innovation Institute, Maiyet, The Nantucket Dreamland Foundation and is a founding circle member of The Nantucket Project. She has also served on the America's Cup Organizing Committee in San Francisco.


List of AMD Athlon microprocessors

Athlon is the name of a family of CPUs designed by AMD, targeted mostly at the desktop market. It has been largely unused as just "Athlon" since 2001 when AMD started naming its processors Athlon XP, but in 2008 began referring to single core 64-bit processors from the AMD Athlon X2 and AMD Phenom product lines. Later the name began being used for some APUs.
Notes.
Note 1:
Athlons use a double data rate (DDR) front-side bus, (EV-6) meaning that the actual data transfer rate of the bus is twice its physical clock rate. The FSB's true data rate, 200 or 266 MT/s, is used in the tables, and the physical clock rates are 100 and 133 MHz, respectively. The multipliers in the tables above apply to the physical clock rate, not the data transfer rate.


Bill Vass

William (Bill) John Vass is the Vice President of Engineering at Amazon Web Services since 2014.
Before joining Amazon Web Services, Bill Vass was president and Chief Executive Officer of Liquid Robotics. He is married to Shari Steele, former Executive Director of the Electronic Frontier Foundation,
and more recently Executive Director of the Tor Project.
Prior to Liquid Robotics, he was the President and Chief Operating Officer of Sun Microsystems Federal (a Sun Microsystems subsidiary focusing on business with government organizations). Before that, he worked for the Department of Defense and the U.S. Army.
His great grandfather was Matthew Fontaine Maury.


Task state segment

The task state segment (TSS) is a structure on x86-based computers which holds information about a task. It is used by the operating system kernel for task management. Specifically, the following information is stored in the TSS:
All this information should be stored at specific locations within the TSS as specified in the IA-32 manuals.
Location of the TSS.
The TSS may reside anywhere in memory. A segment register called the task register (TR) holds a segment selector that points to a valid TSS segment descriptor which resides in the GDT (a TSS descriptor may not reside in the LDT). Therefore, to use a TSS the following must be done by the operating system kernel:
For security purposes, the TSS should be placed in memory that is accessible only to the kernel.
Task register.
The TR register is a 16-bit register which holds a segment selector for the TSS. It may be loaded through the LTR instruction. LTR is a privileged instruction and acts in a manner similar to other segment register loads. The task register has two parts: a portion visible and accessible by the programmer and an invisible one that is automatically loaded from the TSS descriptor.
Register states.
The TSS may contain saved values of all the x86 registers. This is used for task switching. The operating system may load the TSS with the values of the registers that the new task needs and after executing a hardware task switch (such as with an IRET instruction) the x86 CPU will load the saved values from the TSS into the appropriate registers. Note that some modern operating systems such as Windows and Linux do not use these fields in the TSS as they implement software task switching.
Note that during a hardware task switch, certain fields of the "old" TSS are updated with the CPU's current register contents before the values from the "new" TSS are read. Thus some TSS fields are read/write, while others are read-only:
The codice_22 field is in fact the very first one read out of the new TSS: since a hardware task switch can also switch to a completely different page table mapping, all the other fields (especially the codice_23) are relative to the new mapping.
I/O port permissions.
The TSS contains a 16-bit pointer to I/O port permissions bitmap for the current task. This bitmap, usually set up by the operating system when a task is started, specifies individual ports to which the program should have access. The I/O bitmap is a bit array of port access permissions; if the program has permission to access a port, a "0" is stored at the corresponding bit index, and if the program does not have permission, a "1" is stored there. If the TSS’ segment limit is less than the full bitmap, all missing bits are assumed to be "1".
The feature operates as follows: when a program issues an x86 I/O port instruction such as IN or OUT (see x86 instruction listings - and note that there are byte-, word- and dword-length versions), the hardware will do an I/O privilege level (IOPL) check to see if the program has access to all I/O ports. If the Current Privilege Level (CPL) of the program is numerically greater than the I/O Privilege level (IOPL) (the program is less-privileged than what the IOPL specifies), the program does not have I/O port access to all ports. The hardware will then check the I/O permissions bitmap in the TSS to see if that program can access the specific port(s) in the IN or OUT instruction. If (all the) relevant bit(s) in the I/O port permissions bitmap is/are clear, the program is allowed access to the port(s), and the instruction is allowed to execute. If (any of) the relevant bit(s) is/are set - or if (any of) the bit(s) is/are past the TSS’ segment limit - the program does not have access and the processor generates a general protection fault. This feature allows operating systems to grant selective port access to user programs.
Inner-level stack pointers.
The TSS contains 6 fields for specifying the new stack pointer when a privilege level change happens. The field SS0 contains the stack segment selector for CPL=0, and the field ESP0/RSP0 contains the new ESP/RSP value for CPL=0. When an interrupt happens in protected (32-bit) mode, the x86 CPU will look in the TSS for SS0 and ESP0 and load their values into SS and ESP respectively. This allows for the kernel to use a different stack than the user program, and also have this stack be unique for each user program.
A new feature introduced in the AMD64 extensions is called the Interrupt Stack Table (IST), which also resides in the TSS and contains logical (segment+offset) stack pointers. If an interrupt descriptor table specifies an IST entry to use (there are 8), the processor will load the new stack from the IST instead. This allows known-good stacks to be used in case of serious errors (NMI or Double fault for example). Previously, the entry for the exception or interrupt in the IDT pointed to a task gate, causing the processor to switch to the task that is pointed by the task gate. The original register values were saved in the TSS current at the time the interrupt or exception occurred. The processor then set the registers, including SS:ESP, to a known value specified in the TSS and saved the selector to the previous TSS. The problem here is that hardware task switching is not supported on AMD64.
Previous TSS link.
This is a 16-bit selector which allows linking this TSS with the previous one. This is only used for hardware task switching. See the IA-32 manuals for details.
Use of TSS in Linux.
Although a TSS could be created for each task running on the computer, Linux kernel only creates one TSS for each CPU and uses them for all tasks. This approach was selected as it provides easier portability to other architectures (for example, the AMD64 architecture does not support hardware task switches), and improved performance and flexibility. Linux only uses the I/O port permission bitmap and inner stack features of the TSS; the other features are only needed for hardware task switches, which the Linux kernel does not use.
Exceptions related to the TSS.
The x86 exception vector 10 is called the Invalid TSS exception (#TS). It is issued by the processor whenever something goes wrong with the TSS access. For example, if an interrupt happens in CPL=3 and is transferring control to CPL=0, the TSS is used to extract SS0 and ESP0/RSP0 for the stack switch. If the task register holds a bad TSS selector, a #TS fault will be generated. The Invalid TSS exception should never happen during normal operating system operation and is always related to kernel bugs or hardware failure.
For more details on TSS exceptions, see Volume 3a, Chapter 6 of the IA-32 manual.
TSS in x86-64 mode.
The x86-64 architecture does not support hardware task switches. However the TSS can still be used in a machine running in the 64 bit extended modes. In these modes the TSS is still useful as it stores:
Also, the task register is expanded in these modes to be able to hold a 64-bit base address.


FFADO

Free FireWire Audio Drivers (FFADO) is a project to provide open-source drivers for FireWire sound interfaces on Linux. The project began as FreeBoB, a driver specifically for FireWire audio devices based on technology made by BridgeCo, which use an interface named BeBoB The current version allows such devices to be accessed via the JACK Audio Connection Kit (JACK).
Following a presentation of a paper at the 2007 Linux Audio Conference outlining the future of the project, on March 26, 2007, it was announced that the project would be renamed to FFADO, as the drivers are being rewritten to include support for other FireWire audio chipsets.


Digita (operating system)


Close (system call)

A close system call is a system call used to close a file descriptor by the kernel. For most file systems, a program terminates access to a file in a filesystem using the close system call. This flushes file buffers, updates file metadata, which may include and end-of-file indicator in the data; de-allocates resources associated with the file (including the file descriptor) and updates the system wide table of files in use. Some programming languages maintain a data structure of files opened by their runtime library and may close when the program terminates. This practice is known as resource acquisition is initialization (RAII). Some operating systems will invoke the codice_1 on files held by a program if it terminates. Some operating systems will invoke the codice_1 syscall as part of an operating system recovery as a result of a system failure.
C library POSIX definition.
The close call is standardized by the POSIX specification
int close (int filedes);
int fclose (FILE *stream);
The function returns zero to indicate the file was closed successfully. If any error occurs, a value of -1 is returned and errno is appropriately set.
The errors that can occur include:


IBM 3270 PC

The IBM 3270 PC (IBM System Unit 5271), released in October 1983, is an IBM PC XT containing additional hardware that, in combination with software, can emulate the behaviour of an IBM 3270 terminal. It can therefore be used both as a standalone computer, and as a terminal to a mainframe.
IBM later released the "3270 AT" (IBM System Unit 5273), which is a similar design based on the IBM PC AT. They also released high-end graphics versions of the 3270 PC in both XT and AT variants. The XT-based versions are called 3270 PC/G and 3270 PC/GX and they use a different System Unit 5371, while their AT counterparts (PC AT/G and PC AT/GX) have System Unit 5373.
Technology.
The additional hardware occupies nearly all the free expansion slots in the computer. It includes a video card which occupies 1-3 ISA slots (depending on what level of graphics support is required), and supports CGA and MDA video modes. The display resolution is 720×350, either on the matching 14-inch color monitor (model 5272) or in monochrome on an MDA monitor.
A further expansion card intercepts scancodes from the 122-key 3270 keyboard, translating them into XT scancodes which are then sent to the normal keyboard connector. This keyboard, officially called the 5271 Keyboard Element, weighs 9.3 pounds.
The final additional card (a 3278 emulator) provides the communication interface to the host mainframe.
Models.
Models 31/51/71 and all P-models, require version 3.0 of the Control Program.
The basic 3270 PC could not be upgraded to the PC/G or PC/GX. These two models use a different basic unit (System Unit 5371), itself priced at $6,580 (for Model 16) without graphics.
Later, AT-based models:
Software.
At its launch, the 3270 PC used the 3270 PC Control Program as its operating system. PC DOS 2.0 (and later 2.1) can run as a task under the Control Program. Only one PC DOS task can be run at any given time, but in parallel with this, the Control Program can run up to four mainframe sessions. The Control Program also provides a basic windowing environment, with up to seven windows; besides the four mainframe and one DOS session, it also provides two notepads. The notepads can be used to copy text from the PC DOS session to the mainframe sessions but not vice versa. Given the small size of the character display, a review by "PC Magazine" concluded that the windowing features were hardly useful, and the notepads even less so. The Control Program was also described as a "memory hog" in this review, using about 200 KB of RAM in a typical configuration. More useful were the specialized PC DOS file transfer utilities that were available (called simply and ), which allow files to be exchanged with the mainframe and provide ASCII/EBCDIC conversion. The list prices for the Control Program and file transfer utilities were $300 and $600, respectively. At the launch of the 3270 PC, the Control Program was the distinguishing software feature between a 3270 PC and an XT with an added 3278 board.
IBM considered the 3270 PC Control Program to be mainframe software, so it did not provide user-installable upgrades. Upgrades had to be installed by expert system programmers.
The PC/G and PC/GX models run a mainframe-graphics-capable version of the Control Program called the Graphics Control Program (GCP). On the mainframe side, the IBM Graphical Data Display Manager (GDDM) release 4 (and later) is compatible with these two workstations. The GDDM provided support for local pan and zoom (without taxing the host mainframe) on the PC/G and PC/GX.
In 1987 IBM released the IBM 3270 Workstation Program, which supports both XT and AT models of the 3270 PCs, as well as the plain XT and AT models (even with an XT or AT keyboard) with a 3278 board. It allows up to six concurrent DOS 3.3 sessions, but the number of mainframe sessions and notepads remained the same (four and two, respectively).
Reception.
"BYTE" in 1984 praised the 3270 PC's 3278 emulation and color monitor, and concluded that the computer was "a must" for those seeking high-quality graphics or mainframe communications.


Supervisory program

A supervisory program or supervisor is a computer program, usually part of an operating system, that controls the execution of other routines and regulates work scheduling, input/output operations, error actions, and similar functions and regulates the flow of work in a data processing system.
It can also refer to a program that allocates computer component space and schedules computer events by task queuing and system interrupts. Control of the system is returned to the supervisory program frequently enough to ensure that demands on the system are met.
Historically, this term was essentially associated with IBM's line of mainframe operating systems starting with OS/360. In other operating systems, the supervisor is generally called the kernel.
In the 1970s, IBM further abstracted the supervisor state from the hardware, resulting in a hypervisor that enabled full virtualization, i.e. the capacity to run multiple operating systems on the same machine totally independently from each other. Hence the first such system was called "Virtual Machine" or "VM".