Seven-segment display character representations
Encyclopedia
The topic of seven-segment display character representations revolves around the various shapes of numerical digit
Numerical digit
A digit is a symbol used in combinations to represent numbers in positional numeral systems. The name "digit" comes from the fact that the 10 digits of the hands correspond to the 10 symbols of the common base 10 number system, i.e...

s, letters
Letter (alphabet)
A letter is a grapheme in an alphabetic system of writing, such as the Greek alphabet and its descendants. Letters compose phonemes and each phoneme represents a phone in the spoken form of the language....

, and punctuation
Punctuation
Punctuation marks are symbols that indicate the structure and organization of written language, as well as intonation and pauses to be observed when reading aloud.In written English, punctuation is vital to disambiguate the meaning of sentences...

 devisable on seven-segment display
Seven-segment display
A seven-segment display , or seven-segment indicator, is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot-matrix displays...

s. Such representation of characters is not standardized by any relevant entity (e.g. ISO
International Organization for Standardization
The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

, IEEE or IEC
International Electrotechnical Commission
The International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...

).

Digit conventions

Two basic conventions can be seen for Hindu-Arabic numerals: segment A is optional for digit 6, segment F for 7, and segment D for 9; also, either BC or EF may represent a 1.

Alphabetic letters

In addition to the ten digits, seven-segment displays can be used to show letters of the latin
Latin alphabet
The Latin alphabet, also called the Roman alphabet, is the most recognized alphabet used in the world today. It evolved from a western variety of the Greek alphabet called the Cumaean alphabet, which was adopted and modified by the Etruscans who ruled early Rome...

, cyrillic
Cyrillic alphabet
The Cyrillic script or azbuka is an alphabetic writing system developed in the First Bulgarian Empire during the 10th century AD at the Preslav Literary School...

 and greek alphabet
Greek alphabet
The Greek alphabet is the script that has been used to write the Greek language since at least 730 BC . The alphabet in its classical and modern form consists of 24 letters ordered in sequence from alpha to omega...

s including punctuation
Punctuation
Punctuation marks are symbols that indicate the structure and organization of written language, as well as intonation and pauses to be observed when reading aloud.In written English, punctuation is vital to disambiguate the meaning of sentences...

, but only few representations are unambiguous and intuitive at the same time: uppercase A, B, C, E, F, G, H, I, J, L, N, O, P, S, U, Y, Z, and lowercase a, b, c, d, e, g, h, i, n, ñ, o, q, r, t, u.
Also, alphabetic letters, and many other characters, are much clearer, and unambiguously shown on the currently ubiquitous and low-priced dot matrix display
Dot matrix display
A dot matrix display is a display device used to display information on machines, clocks, railway departure indicators and many other devices requiring a simple display device of limited resolution...

s, as well as on fourteen-segment
Fourteen-segment display
A fourteen-segment 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 common seven-segment display, having an additional four diagonal and two vertical segments with the middle horizontal segment...

 and sixteen-segment displays. All this obviates the need for seven-segment displays to show letters in all but the most special cases.

One such special case is the display of the letters A–F when denoting the hexadecimal
Hexadecimal
In mathematics and computer science, hexadecimal is a positional numeral system with a radix, or base, of 16. It uses sixteen distinct symbols, most often the symbols 0–9 to represent values zero to nine, and A, B, C, D, E, F to represent values ten to fifteen...

 values (digits) 10–15. These are needed on some scientific calculators, and are used with some test displays on electronic equipment. Although there is no official standard, most devices displaying hex digits use the unique forms shown in the leftmost column of the Latin alphabet section below — uppercase A, C, E, and F, and lowercase b and d.

All in all, ad hoc
Ad hoc
Ad hoc is a Latin phrase meaning "for this". It generally signifies a solution designed for a specific problem or task, non-generalizable, and not intended to be able to be adapted to other purposes. Compare A priori....

 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.

Display pattern tables

The tables below show alternative seven-segment display patterns for the Hindu-Arabic numerals, the 26 letters of the English language part of the Latin alphabet
Latin alphabet
The Latin alphabet, also called the Roman alphabet, is the most recognized alphabet used in the world today. It evolved from a western variety of the Greek alphabet called the Cumaean alphabet, which was adopted and modified by the Etruscans who ruled early Rome...

, and the Greek alphabet
Greek alphabet
The Greek alphabet is the script that has been used to write the Greek language since at least 730 BC . The alphabet in its classical and modern form consists of 24 letters ordered in sequence from alpha to omega...

. Finally, some examples of words spelled using the patterns are shown.

Hindu-Arabic numerals

0 1 2 3 4 5 6 7 8 9



Latin alphabet

A, a; @
At sign
The at sign , also called the ampersat, apetail, arroba, atmark, at symbol, commercial at or monkey tail, is formally an abbreviation of the accounting and commercial invoice term "at the rate of"...


B, b


C, c

D, d


E, e

F, f
G, g

H, h

I, i

J, j



K, k




L, l



M, m




N, n


O, o

P, p
Q, q

R, r


S, s, ſ
S
S is the nineteenth letter in the ISO basic Latin alphabet.-History: Semitic Šîn represented a voiceless postalveolar fricative . Greek did not have this sound, so the Greek sigma came to represent...



T, t



U, u

V, v



W, w




X, x

Y, y



Z, z





Greek alphabet

Α, α
Alpha (letter)
Alpha is the first letter of the Greek alphabet. In the system of Greek numerals it has a value of 1. It was derived from the Phoenician letter Aleph...

Β, β
Beta (letter)
Beta is the second letter of the Greek alphabet. In Ancient Greek, beta represented the voiced bilabial plosive . In Modern Greek, it represents the voiced labiodental fricative ....


Γ, γ
Gamma
Gamma is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. It was derived from the Phoenician letter Gimel . Letters that arose from Gamma include the Roman C and G and the Cyrillic letters Ge Г and Ghe Ґ.-Greek:In Ancient Greek, gamma represented a...

Δ, δ
Delta (letter)
Delta is the fourth letter of the Greek alphabet. In the system of Greek numerals it has a value of 4. It was derived from the Phoenician letter Dalet...


Ε, ε
Epsilon
Epsilon is the fifth letter of the Greek alphabet, corresponding phonetically to a close-mid front unrounded vowel . In the system of Greek numerals it has a value of 5. It was derived from the Phoenician letter He...

Ζ, ζ
Zeta (letter)
Zeta is the sixth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 7. It was derived from the Phoenician letter Zayin...

Η, η
Eta (letter)
Eta ) is the seventh letter of the Greek alphabet. Originally denoting a consonant /h/, its sound value in the classical Attic dialect of Ancient Greek was a long vowel , raised to in medieval Greek, a process known as itacism.In the system of Greek numerals it has a value of 8...

Θ, θ
Theta
Theta is the eighth letter of the Greek alphabet, derived from the Phoenician letter Teth...

Ι, ι
Iota
Iota is the ninth letter of the Greek alphabet. In the system of Greek numerals it has a value of 10. It was derived from the Phoenician letter Yodh . Letters that arose from this letter include the Roman I and J and the Cyrillic І , Yi , Je , and iotified letters .Iota represents...

Λ, λ
Lambda
Lambda is the 11th letter of the Greek alphabet. In the system of Greek numerals lambda has a value of 30. Lambda is related to the Phoenician letter Lamed . Letters in other alphabets that stemmed from lambda include the Roman L and the Cyrillic letter El...

Μ, μ
Mu (letter)
Carlos Alberto Vives Restrepo is a Grammy Award and three-time Latin Grammy Award winning-Colombian singer, composer and actor.-Biography:...

Ξ, ξ
Ο, ο
Omicron
Omicron is the 15th letter of the Greek alphabet. In the system of Greek numerals it has a value of 70. It is rarely used in mathematics because it is indistinguishable from the Latin letter O and easily confused with the digit 0...


Π, π
Pi (letter)
Pi is the sixteenth letter of the Greek alphabet, representing . In the system of Greek numerals it has a value of 80. Letters that arose from pi include Cyrillic Pe , Coptic pi , and Gothic pairthra .The upper-case letter Π is used as a symbol for:...


Ρ, ρ
Rho
Rho is the 17th letter of the Greek alphabet. In the system of Greek numerals, it has a value of 100. It is derived from Semitic resh "head"...

Σ (C)
Sigma
Sigma is the eighteenth letter of the Greek alphabet, and carries the 'S' sound. In the system of Greek numerals it has a value of 200. When used at the end of a word, and the word is not all upper case, the final form is used, e.g...


Examples

The following phrases come from a portable media player
Portable media player
A portable media player or digital audio player, is a consumer electronics device that is capable of storing and playing digital media such as audio, images, video, documents, etc. the data is typically stored on a hard drive, microdrive, or flash memory. In contrast, analog portable audio...

's seven-segment display. They give a good illustration of an application where a 7-segment display may be sufficient for displaying letters, since the relevant messages are neither life/mission 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
Fourteen-segment display
A fourteen-segment 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 common seven-segment display, having an additional four diagonal and two vertical segments with the middle horizontal segment...

- or 16-segment display, if not a dot matrix
Dot matrix display
A dot matrix display is a display device used to display information on machines, clocks, railway departure indicators and many other devices requiring a simple display device of limited resolution...

one.
On   Off
Open   Close
Play   Pause
Stop   (Play) List
Track   Repeat
Shuffle   Random
Tune  


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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