In computer architecture, 12-bit integers, memory addresses, or other data units are those that are 12 bits (1.5 octets) wide. Also, 12-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size.

Possibly the best-known 12-bit CPU is the PDP-8 and its relatives, such as the Intersil 6100 microprocessor produced in various incarnations from August 1963 to mid-1990. Many analog to digital converters (ADCs) have a 12-bit resolution. Some PIC microcontrollers use a 12-bit word size.

12 binary digits, or 3 nibbles (a 'tribble'), have 4096 (10000 octal, 1000 hexadecimal) distinct combinations. Hence, a microprocessor with 12-bit memory addresses can directly access 4096 words (4 Kw) of word-addressable memory. At a time when six-bit character codes were common a 12-bit word, which could hold two characters, was a convenient size. IBM System/360 instruction formats use a 12-bit displacement field which, added to the contents of a base register, can address 4096 bytes of memory.

List of 12-bit computer systems

See also


Apple ProRes

Apple ProRes is a high quality (although still lossy) video compression format developed by Apple Inc. for use in post-production that supports up to 8K. It is the successor of the Apple Intermediate Codec and was introduced in 2007 with Final Cut Studio 2. It is widely used as a final format delivery method for HD broadcast files in commercials, features, Blu-ray and streaming.

Color depth

Color depth or colour depth (see spelling differences), also known as bit depth, is either the number of bits used to indicate the color of a single pixel, in a bitmapped image or video framebuffer, or the number of bits used for each color component of a single pixel. For consumer video standards, such as High Efficiency Video Coding (H.265), the bit depth specifies the number of bits used for each color component. When referring to a pixel, the concept can be defined as bits per pixel (bpp), which specifies the number of bits used. When referring to a color component, the concept can be defined as bits per component, bits per channel, bits per color (all three abbreviated bpc), and also bits per pixel component, bits per color channel or bits per sample (bps). Color depth is only one aspect of color representation, expressing the precision with which colors can be expressed; the other aspect is how broad a range of colors can be expressed (the gamut). The definition of both color precision and gamut is accomplished with a color encoding specification which assigns a digital code value to a location in a color space.


DECtape (originally called Microtape) is a magnetic tape data storage medium used with many Digital Equipment Corporation computers, including the PDP-6, PDP-8, LINC-8, PDP-9, PDP-10, PDP-11, PDP-12, and the PDP-15. On DEC's 32-bit systems, VAX/VMS support for it was implemented but did not become an official part of the product lineup.

DECtapes are 3/4 inch (19 mm) wide, and formatted into blocks of data that can each be read or written individually. Each tape stores 184K 12-bit PDP-8 words or 144K 18-bit words. Block size is 128 12-bit words (for the 12-bit machines), or 256 18-bit words for the other machines (16, 18, 32, or 36 bit systems). From a programming point of view, DECtape behaves like a very slow disk drive.

File Allocation Table

File Allocation Table (FAT) is a computer file system architecture and a family of industry-standard file systems utilizing it. The FAT file system is a continuing standard which borrows source code from the original, legacy file system and proves to be simple and robust. It offers useful performance even in lightweight implementations, but cannot deliver the same performance, reliability and scalability as some modern file systems. It is, however, supported for compatibility reasons by nearly all currently developed operating systems for personal computers and many mobile devices and embedded systems, and thus is a well-suited format for data exchange between computers and devices of almost any type and age from 1981 up to the present.

Originally designed in 1977 for use on floppy disks, FAT was soon adapted and used almost universally on hard disks throughout the DOS and Windows 9x eras for two decades. As disk drives evolved, the capabilities of the file system have been extended accordingly, resulting in three major file system variants: FAT12, FAT16 and FAT32. The FAT standard has also been expanded in other ways while generally preserving backward compatibility with existing software.

With the introduction of more powerful computers and operating systems, as well as the development of more complex file systems for them, FAT is no longer the default file system for usage on Microsoft Windows computers.FAT file systems are still commonly found on floppy disks, flash and other solid-state memory cards and modules (including USB flash drives), as well as many portable and embedded devices. FAT is the standard file system for digital cameras per the DCF specification.

JPEG Network Graphics

JPEG Network Graphics (JNG, ) is a JPEG-based graphics file format which is closely related to PNG: it uses the PNG file structure (with a different signature) as a container format to wrap JPEG-encoded image data.

JNG was created as an adjunct to the MNG animation format, but may be used as a stand-alone format. JNG files embed an 8-bit or 12-bit JPEG datastream in order to store color data, and may embed another datastream (1, 2, 4, 8, 16-bit PNG, or 8-bit JPEG grayscale image) for transparency information. However, a JNG may contain two separate JPEG datastreams for color information (one 8-bit and one 12-bit) to permit decoders that are unable to (or do not wish to) handle 12-bit datastreams to display the 8-bit datastream instead, if one is present.

Version 1.0 of the JNG specification was released on January 31, 2001 (initially as part of the MNG specification). Usually, all the applications supporting the MNG file format can handle JNG files too. For example, Konqueror has native MNG/JNG support, and MNG/JNG plugins are available for Opera, Internet Explorer, and Mozilla Firefox. The Mozilla Application Suite (and hence Netscape) originally supported MNG/JNG, but native support was removed in Mozilla 1.5a by developers, and Mozilla has not supported the format since, despite requests from its users. Safari does not support MNG/JNG.

JNG enhances the capabilities of the JFIF format (the usual JPEG file format) by supporting transparency, two consecutive color streams (one 8-bit and the other 12-bit), and other useful PNG features like color correction, gamma correction, embedded color profiles, PNG-style metadata, checksums, etc. The transparency information inside a JNG file (as an alpha channel) can be saved either in lossless PNG format or in lossy JPEG format. This way, users can benefit from the power of JPEG compression while preserving lossless (PNG-compressed) transparency information.

The chunk-based structure of JNG files is essentially the same as that of PNG files, differing only in the slightly different signature and the use of different chunks.

JNG does not have a registered Internet media type, but image/x-jng can be used.


The LINC (Laboratory INstrument Computer) is a 12-bit, 2048-word transistorized computer. The LINC is considered by some the first minicomputer and a forerunner to the personal computer. Originally named the "Linc", suggesting the project's origins at MIT's Lincoln Laboratory, it was renamed LINC after the project moved from the Lincoln Laboratory. The LINC was designed by Wesley A. Clark and Charles Molnar.

The LINC and other "MIT Group" machines were designed at MIT and eventually built by Digital Equipment Corporation (DEC) and Spear Inc. of Waltham, Massachusetts (later a division of Becton, Dickinson and Company). The LINC sold for more than $40,000 at the time. A typical configuration included an enclosed 6'X20" rack, four boxes holding tape drives, a small display, a control panel, and a keyboard.

Although the LINC's instruction set was small, it was larger than the tiny PDP-8 instruction set.

The LINC interfaced well with laboratory experiments. Analog inputs and outputs were part of the basic design. It was designed in 1962 by Charles Molnar and Wesley Clark at Lincoln Laboratory, Massachusetts, for NIH researchers. The LINC's design was literally in the public domain, perhaps making it unique in the history of computers. The number of LINCs and who built them is a minor subject of debate in the 12-bit-word community. One account states that a dozen LINC computers were assembled by their eventual biologist users in a 1963 summer workshop at MIT. Digital Equipment Corporation (starting in 1964) and Spear Inc. of Waltham, MA. manufactured them commercially.

DEC's pioneer C. Gordon Bell states that the LINC project began in 1961, with first delivery in March 1962, and the machine was not formally withdrawn until December 1969. A total of 50 were built (all using DEC System Module Blocks and cabinets), most at Lincoln Labs, housing the desktop instruments in four wooden racks. The first LINC included two oscilloscope displays. Twenty-one were sold by DEC at $43,600 (equivalent to $361,100 in 2018), delivered in the Production Model design. In these, the tall cabinet sitting behind a white Formica-covered table held two somewhat smaller metal boxes holding the same instrumentation, a Tektronix display oscilloscope over the "front panel" on the user's left, a bay for interfaces over two LINC-Tape drives on the user's right, and a chunky keyboard between them. The standard program development software (an assembler/editor) was designed by Mary Allen Wilkes; the last version was named LAP6 (LINC Assembly Program 6).

List of Nokia products

The following is a list of products branded by Nokia.

MPEG-4 Part 2

MPEG-4 Part 2, MPEG-4 Visual (formally ISO/IEC 14496-2) is a video compression format developed by MPEG. It belongs to the MPEG-4 ISO/IEC standards. It is a discrete cosine transform compression standard, similar to previous standards such as MPEG-1 Part 2 and H.262/MPEG-2 Part 2. Several popular codecs including DivX, Xvid and Nero Digital implement this standard.

Note that MPEG-4 Part 10 defines a different format from MPEG-4 Part 2 and should not be confused with it. MPEG-4 Part 10 is commonly referred to as H.264 or AVC, and was jointly developed by ITU-T and MPEG.

MPEG-4 Part 2 is H.263 compatible in the sense that a basic H.263 bitstream is correctly decoded by an MPEG-4 Video decoder. (MPEG-4 Video decoder is natively capable of decoding a basic form of H.263.) In MPEG-4 Visual, there are two types of video object layers: the video object layer that provides full MPEG-4 functionality, and a reduced functionality video object layer, the video object layer with short headers (which provides bitstream compatibility with base-line H.263). MPEG-4 Part 2 is partially based on ITU-T H.263. The first MPEG-4 Video Verification Model (simulation and test model) used ITU-T H.263 coding tools together with shape coding.

NCR 315

The NCR 315 Data Processing System, released in January 1962 by NCR, is an obsolete second-generation computer. All printed circuit boards use resistor–transistor logic (RTL) to create the various logic elements. It uses 12-bit slab memory structure using magnetic core memory. The instructions can use a memory slab as either two 6-bit alphanumeric characters or as three 4-bit BCD digits.

Basic memory is 5000 "slabs" (10,000 characters or 15,000 decimal digits) of handmade core memory, which is expandable to a maximum of 40,000 slabs (80,000 characters or 120,000 decimal digits) in four refrigerator-size cabinets. The main processor includes three cabinets and a console section that houses the power supply, keyboard, output writer (an IBM electric typewriter), and a panel with lights that indicate the current status of the program counter, registers, arithmetic accumulator, and system errors. Input/Output is by direct parallel connections to each type of peripheral through a two-cable bundle with 1-inch-thick cables. Some devices like magnetic tape and the CRAM are daisy-chained to allow multiple drives to be connected.

The central processor (315 Data Processor) weighed about 1,325 pounds (601 kg).Later models in this series include the 315-100 and the 315-RMC (Rod Memory Computer).

Nokia 3200

The Nokia 3200 is a mobile phone, part of the Nokia Expression (youth) series and announced on 12 September 2003. It is based on the Nokia Series 40 platform. Its main feature set is a mix between the Nokia 3100 and Nokia 7250i. Like the Nokia 7250i, the phone has an integrated CIF camera. Other features include an XHTML browser, alarm clock, flashlight, EDGE and FM stereo radio with a 128 × 128 12-bit (4096) color screen. The phone has multimedia features such as picture and text messaging. Features carried over from the Nokia 3100 include ringer profiles and voice memo capability. It also has Java games (max downloadable size of game or application cannot exceed 64 kB). The phone has an extensive calendar with a lunar calendar (for the Chinese/Asian variants). The flashlight is located under the phone and can be activated by holding the "star" (asterisk) key. The camera is on the back of the phone. The 3200 can also play both polyphonic and monophonic ringtones. The phone's visual interface in its menu system is similar to that of the Nokia 3100, using large, static icons rather than animated ones.

An interesting feature present in this phone is that the face plate system allows users to print out their own cut-out cover designs and use it in the phone. The official special released designs include "Snowboard," "Street life" and "Urban chic". It was thus marketed as being "fun and funky" with a unique style.While the phone's feature set was an improvement over the Nokia 3100, the 3200 did not quite enjoy the popularity that the 3100 did. Some known complaints with the phone included its low CIF resolution camera, quirky circular keypad design, and its small 12-bit color display.

The Nokia 3220 addresses some of the 3200's flaws, including a better VGA resolution camera, more standard keypad layout, and 16-bit color display.

Nokia 6100

The Nokia 6100 is a popular mid-range Nokia mobile phone that was available from 2002 to 2005. It was announced on 4 September 2002 (together with Nokia 7250).The Nokia 6100 was Nokia's lightest phone with a full 12-key keypad at the time. Combined with its battery, it weighs only 76 grams (2.68 ounces) and measures 102 x 44 x 13.5 mm. Its smaller size compared with other contemporary phones might make it difficult for the elderly, or people with large fingers, to use its keypad. The phone supports Xpress-On covers, and is packaged along with any of 4 colours. Its feature set is very similar to the Nokia 7210, although with a more conservative design.The Nokia 6100 has a display with a resolution of 128 x 128 pixels, featuring 12-bit color (allowing for 4096 possible colors). Its features include Internet connectivity via GPRS, an infrared port, inbuilt calendar and polyphonic ring tones. It does not have a camera. It could be considered the true successor of the Nokia 8210 and Nokia 8250 in terms of design functionality and its small flat size.

The LCD screen comes in two main versions which are very similar. One version of the LCD is controlled by an EPSON S1D15G00 driver chip, whilst the other version uses a Philips PCF8833 instead. There are also clones of these drivers. Early releases had a slightly blurry, yellower and duller screen compared with the Nokia 7210 and 6610 of the same period, but later screens improved this shortcoming.

Both driver chips allow the display to be used with 8-bit (256 colors) or 12-bit (4096 colors) RGB. Only the Philips version provides, on a low-level, the ability to use 16-bit RGB. This is achieved through dithering. 16-bit RGB gives 65536 different colors, sixteen times that available in the Nokia 12-bit RGB colour mode.


The PDP-5 was Digital Equipment Corporation's first 12-bit computer, introduced in 1963.


The PDP-8 was a 12-bit minicomputer produced by Digital Equipment Corporation (DEC). It was the first commercially successful minicomputer, with over 50,000 examples being sold over the model's lifetime. Its basic design followed the pioneering LINC but had a smaller instruction set, which was an expanded version of the PDP-5 instruction set. Similar machines from DEC were the PDP-12 which was a modernized version of the PDP-8 and LINC concepts, and the PDP-14 industrial controller system.

The earliest PDP-8 model, informally known as a "Straight-8", was introduced on 22 March 1965 priced at $18,500 (equivalent to about $150,000 in 2018). It used diode–transistor logic packaged on flip chip cards in a machine about the size of a small household refrigerator. It was the first computer to be sold for under $20,000, making it the best-selling computer in history at that time. The Straight-8 was supplanted in 1966 by the PDP-8/S, which was available in desktop and rack-mount models. Using a one-bit serial arithmetic logic unit (ALU) allowed the PDP-8/S to be smaller and less expensive, although slower than the original PDP-8. A basic 8/S sold for under $10,000, the first machine to reach that milestone.Later systems (the PDP-8/I and /L, the PDP-8/E, /F, and /M, and the PDP-8/A) returned to a faster, fully parallel implementation but use much less costly transistor–transistor logic (TTL) MSI logic. Most surviving PDP-8s are from this era. The PDP-8/E is common, and well-regarded because many types of I/O devices were available for it. The last commercial PDP-8 models introduced in 1979 were called "CMOS-8s", based on CMOS microprocessors. They were not priced competitively, and the offering failed. Intersil sold the integrated circuits commercially through to 1982 as the Intersil 6100 family. By virtue of their CMOS technology they had low power requirements and were used in some embedded military systems.

The chief engineer who designed the initial version of the PDP-8 was Edson de Castro, who later founded Data General.

Programmable system-on-chip

PSoC (programmable system-on-chip) is a family of microcontroller integrated circuits by Cypress Semiconductor. These chips include a CPU core and mixed-signal arrays of configurable integrated analog and digital peripherals.

Roland S-50

The Roland S-50 is a 61 key 12-bit sampler keyboard produced by the Roland Corporation in 1986. It featured a 3.5" DSDD Floppy Disk Drive and had external CRT monitor support to facilitate editing of samples. It could hold up to 32 samples. A rack mounted version was also available which featured expanded memory.

Sampler (musical instrument)

A sampler is an electronic or digital musical instrument similar in some respects to a synthesizer, but instead of generating new sounds with voltage-controlled oscillators, it uses sound recordings (or "samples") of real instrument sounds (e.g., a piano, violin or trumpet), excerpts from recorded songs (e.g., a five-second bass guitar riff from a funk song) or other sounds (e.g., sirens and ocean waves). The samples are loaded or recorded by the user or by a manufacturer. These sounds are then played back by means of the sampler program itself, a MIDI keyboard, sequencer or another triggering device (e.g., electronic drums) to perform or compose music. Because these samples are usually stored in digital memory, the information can be quickly accessed. A single sample may often be pitch-shifted to different pitches to produce musical scales and chords.

Often samplers offer filters, effects units, modulation via low frequency oscillation and other synthesizer-like processes that allow the original sound to be modified in many different ways. Most samplers have Multitimbrality capabilities – they can play back different sounds simultaneously. Many are also polyphonic – they are able to play more than one note at the same time.

Syllable (computing)

In computing, a syllable is a name for a platform-dependent unit of information storage. Depending on the target hardware, various bit widths (and sometimes internal groupings) are associated with it. Commonly used in the 1960s and 1970s, the term has mostly fallen into disuse in favour of terms like byte or word.


3-bit syllables: some experimental CISC designs

8-bit syllables: English Electric KDF9 (represented as syllabic octals in this context) and Burroughs large systems (see also: Burroughs B6x00-7x00 instruction set)

12-bit syllables: NCR computers such as the NCR 315 (also called slabs in this context) and Burroughs large systems

13-bit syllables: Saturn Launch Vehicle Digital Computer (LVDC) and Gemini Spacecraft On-Board Computer (OBC)


The UNI/O bus is an asynchronous serial bus created by Microchip Technology for low speed communication in embedded systems. The bus uses a master/slave configuration, requiring one signal to pass data between devices. The first devices supporting the UNI/O bus were released in May 2008.

Yamaha YM2610

YM2610, a.k.a. OPNB, is a fifteen-channel sound chip developed by Yamaha. It's a member of Yamaha's OPN family of FM synthesis chips, and related to the YM2608. It was most notably used in SNK's Neo Geo arcade and home game systems, along with other arcade game systems. The YM2610 was used in conjunction with a YM3016 stereo DAC.

The YM2610 has the following features:

Four concurrent FM channels (voices), four operators per channel, DAC compatible with YM3016

Three SSG channels: compatible with YM2149 (Atari ST)

One programmable noise channel

ADPCM-A: Six ADPCM channels, fixed pitch, 18.5 kHz sampling rate at 12-bit from 4-bit data

ADPCM-B: One ADPCM channel, variable pitch, 18.5–55.5 kHz sampling rate

Two interval timers

A low frequency oscillator (LFO)The YM2610B variant added two extra FM channels for a total of six, but was identical in every other feature. It was used in Taito's arcade boards, such as the Taito Z System, amongst others.

Instruction set
Word size
Core count

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