The topic of

seven-segment display A seven-segment display is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot matrix displays. Seven-segment displays are widely used in digital clocks, electronic meters, basic ...

character representations revolves around the various shapes of

numerical digit A numerical digit (often shortened to just digit) is a single symbol used alone (such as "2") or in combinations (such as "25"), to represent numbers in a positional numeral system. The name "digit" comes from the fact that the ten digits (Latin ...

letters Letter, letters, or literature may refer to: Characters typeface * Letter (alphabet), a character representing one or more of the sounds used in speech; any of the symbols of an alphabet. * Letterform, the graphic form of a letter of the alphabe ...

, and

punctuation Punctuation (or sometimes interpunction) is the use of spacing, conventional signs (called punctuation marks), and certain typographical devices as aids to the understanding and correct reading of written text, whether read silently or aloud. An ...

devisable on

s. Such representation of characters is not standardized by any relevant entity (e.g.

ISO ISO is the most common abbreviation for the International Organization for Standardization. ISO or Iso may also refer to: Business and finance * Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007 * Iso ...

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operat ...

IEC The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and r ...

). Unicode provides encoding codepoint for segmented digits in Unicode 13.0 in

Symbols for Legacy Computing Symbols for Legacy Computing is a Unicode block containing graphic characters that were used for various home computers from the 1970s and 1980s and in Teletext broadcasting standards. It includes characters from the Amstrad CPC, MSX, Mattel Aqu ...

block.

Digit

Two basic conventions are in common use for some Arabic numerals: display segment ''A'' is optional for digit 6 (/), segment ''F'' for 7 (/), and segment ''D'' for 9 (/). Although ''EF'' () could also be used to represent digit 1, this seems to be rarely done if ever. ''CDEG'' () is occasionally encountered on older calculators to represent 0. In Unicode 13.0, 10 codepoints had been given for segmented digits 0–9 in the

block:

Alphabet

In addition to the ten digits, seven-segment displays can be used to show most letters of the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

, Cyrillic and

Greek alphabet The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as w ...

s including

. One such special case is the display of the letters A–F when denoting the hexadecimal values (digits) 10–15. These are needed on some scientific calculators, and are used with some testing displays on electronic equipment. Although there is no official standard, today most devices displaying hex digits use the unique forms shown to the right: uppercase A, lowercase b, uppercase C, lowercase d, uppercase E and F. To avoid ambiguity between the digit 6 and the letter b the digit 6 is displayed with segment A lit. However, this modern scheme was not always followed in the past, and various other schemes could be found as well: * The

Texas Instruments Texas Instruments Incorporated (TI) is an American technology company headquartered in Dallas, Texas, that designs and manufactures semiconductors and various integrated circuits, which it sells to electronics designers and manufacturers globa ...

seven-segment display decoder chips 7446/7447/7448/7449 and 74246/74247/74248/74249 and the Siemens FLH551-7448/555-8448 chips used truncated versions of "2", "3", "4", "5" and "6" for digits A–G. Digit F (1111 binary) was blank. * Soviet

programmable calculator Programmable calculators are calculators that can automatically carry out a sequence of operations under control of a stored program. Most are Turing complete, and, as such, are theoretically general-purpose computers. However, their user inter ...

s like the Б3-34 instead used the symbols "−", "L", "C", "Г", "E", and " " (space) to display hexadecimal numbers above nine. (The Б3-34 character set allowed for a cross-alphabet display of the English word "Error" as either EГГ0Г or 3ГГ0Г, depending on the error, in all-numeric form during error messages.) * Not all 7-segment decoders were suitable to display digits above nine at all. For comparison, the

National Semiconductor National Semiconductor was an American semiconductor manufacturer which specialized in analog devices and subsystems, formerly with headquarters in Santa Clara, California. The company produced power management integrated circuits, display dr ...

MM74C912 displayed "o" for A and B, "−" for C, D and E, F, and blank for G. * The CD4511 even just displayed blanks. * The Magic Black Box, an electronic version of the

Magic 8-Ball The Magic 8 Ball is a plastic sphere, made to look like an oversized , that is used for fortune-telling or seeking advice. It was invented in 1946 by Albert C. Carter and Abe Bookman and is currently manufactured by Mattel. The user asks a yes� ...

toy, used a ROM to generate 64 different 16-character alphanumeric messages on a LED display. It could not generate K, M, V, W, and X but it could generate a question mark. For the remainder of characters,

ad hoc Ad hoc is a Latin phrase meaning literally 'to this'. In English, it typically signifies a solution for a specific purpose, problem, or task rather than a generalized solution adaptable to collateral instances. (Compare with '' a priori''.) C ...

and corporate solutions dominate the field of using seven-segment displays to show general words and phrases. Such applications of seven-segment displays are usually not considered essential and are only used for basic notifications on consumer electronics appliances (as is the case of this article's example phrases), and as internal test messages on equipment under development. Certain letters (M, V, W, X in the Latin alphabet) cannot be expressed unambiguously at all due to either diagonal strokes, more than two vertical strokes, or inability to distinguish them from other letters, while others can only be expressed in either capital form or lowercase form but not both. The

Nine-segment display A nine-segment display is a type of display based on nine segments that can be turned on or off according to the graphic pattern to be produced. It is an extension of the more common seven-segment display, having an additional two diagonal or ver ...

fourteen-segment display A fourteen-segment display (FSD) (sometimes referred to as a starburst display or Union Jack display) is a type of display based on 14 segments that can be turned on or off to produce letters and numerals. It is an expansion of the more com ...

sixteen-segment display A sixteen-segment display (SISD) is a type of display based on sixteen segments that can be turned on or off to produce a graphic pattern. It is an extension of the more common seven-segment display, adding four diagonal and two vertical segments ...

dot matrix display A dot-matrix display is a low cost electronic digital display device that displays information on machines such as clocks, watches, calculators, and many other devices requiring a simple alphanumeric (and/or graphic) display device of limited res ...

are more commonly used for hardware that requires the display of messages that are more than trivial.

Examples

The following phrases come from a portable media player's seven-segment display. They give a good illustration of an application where a seven-segment display may be sufficient for displaying letters, since the relevant messages are neither critical nor in any significant risk of being misunderstood, much due to the limited number and rigid domain specificity of the messages. As such, there is no direct need for a more expressive display, in this case, although even a slightly wider repertoire of messages would require at least a 14-segment display or a

dot matrix A dot matrix is a 2-dimensional patterned array, used to represent characters, symbols and images. Most types of modern technology use dot matrices for display of information, including mobile phones, televisions, and printers. The system is al ...

one.

References

{{reflist, refs= {{cite web , title=Application Note 3210 – Quick-Start: Driving 7-Segment Displays with the MAX6954 , author= , publisher=

Maxim Integrated Maxim Integrated, a subsidiary of Analog Devices, designs, manufactures, and sells analog and mixed-signal integrated circuits for the automotive, industrial, communications, consumer, and computing markets. Maxim's product portfolio includes p ...

, orig-date=2004-06-25 , edition=3 , date=March 2008 , url=http://datasheets.maximintegrated.com/en/ds/MAX6955.pdf , type=Application note , access-date=2013-05-06 , url-status=live, archive-url=https://web.archive.org/web/20170320002007/https://datasheets.maximintegrated.com/en/ds/MAX6955.pdf , archive-date=2017-03-20 {{cite web , publisher=

, title=Driving 7-Segment Displays , date=2004 , url=http://www.maximintegrated.com/app-notes/index.mvp/id/3210 , access-date=2017-03-20 , url-status=live , archive-url=https://web.archive.org/web/20170320000854/https://www.maximintegrated.com/en/app-notes/index.mvp/id/3210 , archive-date=2017-03-20 {{cite book , title=electronic hexadecimal calculator/converter SR-22 , publisher=

Texas Instruments Incorporated Texas Instruments Incorporated (TI) is an American technology company headquartered in Dallas, Texas, that designs and manufactures semiconductors and various integrated circuits, which it sells to electronics designers and manufacturers globall ...

, date=1974 , page=7 , edition=Revision A , id=1304-389 Rev A , url=http://www.datamath.net/Manuals/SR-22_US.pdf , access-date=2017-03-20 , url-status=live , archive-url=https://web.archive.org/web/20170320001329/http://www.datamath.net/Manuals/SR-22_US.pdf , archive-date=2017-03-20 {{cite book , title=electronic calculator – TI programmer , publisher=

, date=1977 , page=7 , url=http://www.datamath.net/Manuals/TI-Programmer_US.pdf , access-date=2017-03-28 , url-status=live , archive-url=https://web.archive.org/web/20170328231050/http://www.datamath.net/Manuals/TI-Programmer_US.pdf , archive-date=2017-03-28 {{cite book , title=electronic calculator – TI LCD programmer , publisher=

, date=1981 , page=8 , url=http://www.datamath.net/Manuals/LCD-Programmer_US.pdf , access-date=2017-03-28 , url-status=live , archive-url=https://web.archive.org/web/20170328231558/http://www.datamath.net/Manuals/LCD-Programmer_US.pdf , archive-date=2017-03-28 {{cite book , title=Werkbuch Elektronik , language=German , author-first=Dieter , author-last=Nührmann , publisher= Franzis-Verlag GmbH , publication-place=Munich, Germany , location=Achim, Bremen, Germany , date=1981 , edition=3 , isbn=3-7723-6543-4 , page=695 {{citation , title=BCD-to-Seven-Segment Decoders/Drivers: SN54246/SN54247/SN54LS247, SN54LS248 SN74246/SN74247/SN74LS247/SN74LS248 , date=March 1988 , orig-date=March 1974 , id=SDLS083 , publisher=

, url=http://www.ralphselectronics.com/ProductImages/SEMI-SN74247N.PDF , access-date=2017-03-30 , url-status=live , archive-url=https://web.archive.org/web/20170329223343/http://www.ralphselectronics.com/ProductImages/SEMI-SN74247N.PDF , archive-date=2017-03-29 , quote=They can be used interchangeable in present or future designs to offer designers a choice between two indicator fonts. The '46A, '47A, 'LS47, and 'LS48 compose the 6 and the 9 without tails and the '246, '247, 'LS247, and 'LS248 compose the 6 and the 0 with tails. Composition of all other characters, including display patterns for BCD inputs above nine, is identical....Display patterns for BCD input counts above 9 are unique symbols to authenticate input conditions. {{cite book , title=Digitaltechnik , author-first1=Klaus , author-last1=Beuth , author-first2=Annette , author-last2=Beuth , language=German , work=Elektronik , volume=4 , publisher={{ill, Vogel Buchverlag, de , location=Würzburg, Germany , date=1990 , edition=7 , isbn=3-8023-0584-1 , pages=301–303 {{cite book , title=Datenblatt FLH551-7448, FLH555-8448, 74248 , publisher= Siemens , language=de {{cite magazine , title=junior cookbook: a few healthy recipes to keep your computer in shape , author-first1=H. P. , author-last1=Diehl , author-first2=H. D. , author-last2=De Mulder , date=April 1981 , volume=1981 , issue=72 , magazine=

elektor :''Elektor (ἠλέκτωρ) is also an ancient Greek name or epithet of the Sun, see Helios.'' ''Elektor'', also known as ''Elektor Magazine'', is a monthly magazine about all aspects of electronics, originally published in the Netherlands as ''E ...

(UK) – up-to-date electronics for lab and leisure , language=en , pages=4-28–4-31 -30 Figure 4, url=https://worldradiohistory.com/UK/Elektor/80s/Elektor-1981-04.pdf , access-date=2020-07-03 , url-status=live , archive-url=https://web.archive.org/web/20200703164044/https://worldradiohistory.com/UK/Elektor/80s/Elektor-1981-04.pdf , archive-date=2020-07-03 {{cite magazine , author-last=Friese , author-first=Michael , title=Electronic Magic Box , magazine=

Popular Electronics ''Popular Electronics'' was an American magazine published by John August Media, LLC, and hosted at TechnicaCuriosa.com. The magazine was started by Ziff-Davis Publishing Company in October 1954 for electronics hobbyists and experimenters. It soo ...

, date=January 1980 , volume=17 , issue=1 , pages=61–66 , url=https://worldradiohistory.com/Archive-Poptronics/80s/1980/Poptronics-1980-01.pdf , access-date=2021-12-30

External links

Seven Segment Optical Character Recognition
Display technology Digital typography Writing systems introduced in the 1900s

Digit

Alphabet

Examples

See also

References

External links