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== Examples ==
== Examples ==
The following phrases come from a [[portable media player]]'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 [[fourteen-segment display|14]]- or [[sixteen-segment display|16-segment display]], if not a [[dot matrix display|dot matrix]] one.
The following phrases come from a [[portable media player]]'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 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 [[fourteen-segment display|14]]- or [[sixteen-segment display|16-segment display]], if not a [[dot matrix display|dot matrix]] one.


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Revision as of 01:28, 9 August 2012

The topic of seven-segment display character representations revolves around the various shapes of numerical digits, letters, and punctuation devisable on seven-segment displays. Such representation of characters is not standardized by any relevant entity (e.g. ISO, IEEE or IEC).

The individual segments of a seven-segment display.

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, Cyrillic and Greek alphabets including punctuation, 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 displays, as well as on fourteen-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 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 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, and the Greek alphabet. Finally, some examples of words spelled using the patterns are shown.

Hindu-Arabic numerals

0 1 2 3 4 5 6 7 8 9
0 0 1 1 2 3 4 5 6 6 7 7 8 9 9


Latin alphabet

A, a; @
A
a/@
B, b
b
b
B
C, c
C
c
D, d
d
d
D
E, e
E
e
F, f
F/f
G, g
G
g
H, h
H
h
I, i
I
I i
J, j
J
J
J
j
K, k
K
K
K
K
k
L, l
L
l
l
l
M, m
M/m
M/m
M/m
M/m
M/m
N, n
n
N
N
O, o
O
o
P, p
P/p
Q, q
q
Q
R, r
r
r
R
S, s, ſ
S/s
S
ſ
T, t
t
t
T
T
U, u
U
u
V, v
V
v
V
v
W, w
W/w
W/w
W/w
W/w
W/w
X, x
X
H
Y, y
Y/y
Y/y
Y/y
Y/y
Z, z
Z/z
Z
z


Greek alphabet

Α, α
Α
Β, β
Β
Β/β
Γ, γ
Γ
Δ, δ
δ
δ
Ε, ε
Ε/ε
Ζ, ζ
Ζ
Η, η
Η
Θ, θ
Θ/θ
Ι, ι
Ι
Λ, λ
Λ/λ
Μ, μ
μ
Ξ, ξ
Ξ
Ο, ο
Ο
ο
Π, π
Π
π
Ρ, ρ
Ρ/ρ
Σ (C)
Σ/Ϲ/ϲ


Examples

The following phrases come from a portable media player'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 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- or 16-segment display, if not a dot matrix one.

On On   Off Off
Open OPEN   Close CLOSE
Play PLAy   Pause PAUSE
Stop Stop   (Play) List LISt
Track TrACK   Repeat Repeat
Shuffle SHUffLE   Random random
Tune Tune  

See also