Sixteen-segment display

Segments layout.

Arabic numerals and letters of the ISO basic Latin alphabet on a typical 16-segment display.

A sixteen-segment display (SISD) , sometimes called a "Union Jack" display or a "British Flag" display^{[citation needed]}, is a type of display based on 16 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, adding four diagonal and two vertical segments and splitting the three horizontal segments in half. Other variants include the fourteen-segment display which splits only the middle horizontal segment.

Often a character generator is used to translate 7-bit ASCII character codes to the 16 bits that indicate which of the 16 segments to turn on or off.^[1]

History

Sixteen-segment displays were originally designed to display alphanumeric characters (Latin letters and Arabic digits). Later they were used to display Thai numerals^[2] and Persian characters.^[3]

Before the advent of inexpensive dot-matrix displays, sixteen and fourteen-segment displays were some of the few options available for producing alphanumeric characters on calculators and other embedded systems. However, they are still sometimes used on VCRs, car stereos, microwave ovens, telephone Caller ID displays, and slot machine readouts.

Sixteen-segment displays may be based on one of several technologies, the three most common optoelectronics types being LED, LCD and VFD. The LED variant is typically manufactured in single or dual character packages, to be combined as needed into text line displays of a suitable length for the application in question.

As with seven and fourteen-segment displays, a decimal point and/or comma may be present as an additional segment, or pair of segments; the comma (used for triple-digit groupings or as a decimal separator in many regions) is commonly formed by combining the decimal point with a closely 'attached' leftwards-descending arc-shaped segment. This way, a point or comma may be displayed between character positions instead of occupying a whole position by itself, which would be the case if employing the bottom middle vertical segment as a point and the bottom left diagonal segment as a comma. Such displays were very common on pinball machines for displaying the score and other information, before the widespread use of dot-matrix display panels.

See also

• Seven-segment display
• Nine-segment display
• Fourteen-segment display
• Dot matrix display
• Nixie tube
• Hexadecimal

References