Editing Binary clock

{{Short description|Clock that displays the time in a binary format}}
{{more footnotes|date=September 2019}}
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! colspan="2" | GMT at page generation (<small>[https://en.wikipedia.org/w/index.php?title=Binary_clock&action=purge Update]</small>)
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| 24-hour time || style="white-space:nowrap" | {{#time:H:i:s}}
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| Expressed in Binary || style="white-space:nowrap" | {{#invoke:BaseConvert|10to2|{{#time:H}}}}:{{#invoke:BaseConvert|10to2|{{#time:i}}}}:{{#invoke:BaseConvert|10to2|{{#time:s}}}}
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| "True" Binary Time<br>(Seconds since start of day) || {{#invoke:BaseConvert|10to2|{{#expr:({{#time:H}}*3600)+({{#time:i}}*60)+{{#time:s}}}}|width=16}}
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A '''binary clock''' is a [[clock]] that displays the time of day in a [[binary numeral system|binary]] format.  Originally, such clocks showed ''each decimal digit'' of [[sexagesimal]] time as a binary value, but presently binary clocks also exist which display hours, minutes, and seconds as binary numbers. Most binary clocks are [[Digital clock|digital]], although [[analog clock|analog]] varieties exist. True binary clocks also exist, which indicate the time by successively halving the day, instead of using hours, minutes, or seconds. Similar clocks, based on [[Gray code]]d binary, also exist. 

== Binary-coded decimal clocks ==
[[File:Binary clock.svg|thumbnail|right|Reading a [[binary-coded decimal]] clock: Add the values of each column of [[Light-emitting diode|LEDs]] to get six decimal digits. There are two columns each for hours, minutes and seconds.]]
[[File:Digital-BCD-clock.jpg|thumbnail|right|Both clocks read 12:15:45.]]

Most common binary clocks  use six columns of [[LED]]s to represent [[0 (number)|zeros]] and [[1 (number)|ones]]. Each column represents a single decimal digit, a format known as [[binary-coded decimal]] (BCD). The bottom row in each column represents 1 (or 2<sup>0</sup>), with each row above representing higher powers of two, up to 2<sup>3</sup> (or 8). 

To read each individual digit in the time, the user adds the values that each illuminated [[light-emitting diode|LED]] represents, then reads these from left to right. The first two columns represent the [[hour]], the next two represent the [[minute]] and the last two represent the [[second]]. Since zero digits are not illuminated, the positions of each digit must be memorized if the clock is to be usable in the dark.

== Binary-coded sexagesimal clocks ==

[[File:Binary clock samui moon.jpg|thumbnail|right|Time Technology's Samui Moon binary-coded sexagesimal wristwatch. This clock reads 3:25.]]

Binary clocks that display time in binary-coded [[sexagesimal]] also exist. Instead of representing each digit of traditional sexagesimal time with one binary number, each component of traditional sexagesimal time is represented with one binary number, that is, using up to 6 bits instead of only 4.

For 24-hour binary-coded sexagesimal clocks, there are 11 or 17 LED lights to show the time. There are 5 LEDs to show the hours, there are 6 LEDs to show the minutes, and there are 6 LEDs to show the seconds (which aren't used in clocks with 11 LED lights).

{| class="wikitable" style="text-align: center;"
|-
| 
! Hours
! Minutes
! Seconds
|-
! 32
|  
| 1
| 1
|-
! 16
| 0
| 0
| 1
|-
! 8
| 1
| 0
| 0
|-
! 4
| 0
| 1
| 0
|-
! 2
| 1
| 0
| 0
|-
! 1
| 0
| 1
| 1
|-
| 
! 10
! 37
! 49
|}

[[File:Binary clock Swiss railway station.jpg|thumbnail|right|Binary large-scale electronic clock, designed by the artist [[Norbert Möslang]], to indicate the time of day on 3 lines in hours, minutes, seconds on the face of the main railway station in [[St. Gallen]], Switzerland. Time indicated is 9 o'clock 25 minutes 46 seconds.]]
A format exists also where hours, minutes and seconds are shown on three lines instead of columns as binary numbers.<ref>{{Cite web|url=https://www.tagblatt.ch/ostschweiz/stgallen-gossau-rorschach/stgallen-verpassen-sie-den-zug-oder-koennen-sie-eine-binaer-uhr-lesen-ld.1013362|title=ST.GALLEN: Verpassen Sie den Zug oder können Sie eine Binär-Uhr lesen?|website=St.Galler Tagblatt|date=6 April 2018 |language=de|access-date=2020-04-02}}</ref>

== Binary time ==
Less commonly, the day could be divided in binary fractions, such as ½ day, ¼ day, etc. The clock would show the time in 16 bits, where the smallest unit would be exactly {{frac|1|65536}} day, or {{frac|675|512}} (about 1.318) seconds.<ref>{{Cite web|url=http://www.abulsme.com/binarytime/|title=Abulsme True Binary Time|website=www.abulsme.com|access-date=2020-04-02}}</ref> An analog format also exists of this type.<ref>{{Cite web|url=http://anthony.liekens.net/index.php/Misc/TrueBinaryTime|archive-url=https://web.archive.org/web/20070202184501/http://anthony.liekens.net/index.php/Misc/TrueBinaryTime|url-status=dead|archive-date=February 2, 2007|title=anthony.liekens.net » Misc » True Binary Time|website=anthony.liekens.net|access-date=2020-04-02}}</ref> However,  it is much easier to write and express this in hexadecimal, which would be [[hexadecimal time]].

==References==
{{Reflist}}

[[Category:Clock designs]]
[[Category:Time measurement systems]]
[[Category:Binary arithmetic]]