In computing FOCAL character set refers to a group of 8-bit single byte

character set Character encoding is the process of assigning numbers to graphical characters, especially the written characters of human language, allowing them to be stored, transmitted, and transformed using digital computers. The numerical values tha ...

s introduced by Hewlett-Packard since 1979. It was used in several RPN

calculator An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics. The first solid-state electronic calculator was created in the early 1960s. Pocket-size ...

s supporting the FOCAL programming language, like the

HP-41C The HP-41C series are programmable, expandable, continuous memory handheld RPN calculators made by Hewlett-Packard from 1979 to 1990. The original model, HP-41C, was the first of its kind to offer alphanumeric display capabilities. Later cam ...

/ CV/ CX as well as the later HP-42S, which was introduced in 1988 and produced up to 1995. As such, it is also used by SwissMicros' DM41/ L, both introduced in 2015, and is implicitly supported by the DM42, introduced in 2017 (although the later calculator utilizes

Free42 The HP-42S RPN Scientific is a programmable RPN Scientific hand held calculator introduced by Hewlett Packard in 1988. It has advanced functions suitable for applications in mathematics, linear algebra, statistical analysis, computer science and ...

, which is based on

Unicode Unicode, formally The Unicode Standard,The formal version reference is is an information technology standard for the consistent encoding, representation, and handling of text expressed in most of the world's writing systems. The standard, ...

internally).

Character set

The character set is derived from

ASCII ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because ...

, but with the control code range and some high bit characters replaced by various special characters. When Hewlett-Packard introduced the HP-42S in 1988, the FOCAL character set was revised to include more characters, including a number of characters already provided by the HP 82240A infrared

thermo printer Thermal printing (or direct thermal printing) is a digital printing process which produces a printed image by passing paper with a thermochromic coating, commonly known as thermal paper, over a print head consisting of tiny electrically heat ...

, which had been introduced in 1986, as part of its extended variant of the 1985 revision of the

HP Roman-8 In computing HP Roman is a family of character sets consisting of HP Roman Extension, HP Roman-8, HP Roman-9 and several variants. Originally introduced by Hewlett-Packard around 1978, revisions and adaptations were published several times up t ...

character set, although at completely different code points. There is no code point definition for the

euro sign The euro sign () is the currency sign used for the euro, the official currency of the eurozone and unilaterally adopted by Kosovo and Montenegro. The design was presented to the public by the European Commission on 12 December 1996. It consi ...

in this character set. Translation from HP-42S character set to the modified HP Roman-8 (supported by HP 82240A etc.) character set:

Character set

See also

Notes

References

Further reading