millfork/docs/lang/text.md

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Text encodings ans escape sequences

Text encoding list

• default – default console encoding (can be omitted)

• scr – default screencodes (usually the same as default, a notable exception are the Commodore computers)

• ascii – standard ASCII

• pet or petscii – PETSCII (ASCII-like character set used by Commodore machines from VIC-20 onward)

• petjp or petsciijp – PETSCII as used on Japanese versions of Commodore 64

• origpet or origpetscii – old PETSCII (Commodore PET with original ROMs)

• oldpet or oldpetscii – old PETSCII (Commodore PET with newer ROMs)

• cbmscr or petscr – Commodore screencodes

• cbmscrjp or petscrjp – Commodore screencodes as used on Japanese versions of Commodore 64

• apple2 – Apple II charset ($A0–$DF)

• bbc – BBC Micro character set

• sinclair – ZX Spectrum character set

• zx80 – ZX80 character set

• zx81 – ZX81 character set

• jis or jisx – JIS X 0201

• iso_de, iso_no, iso_se, iso_yu – various variants of ISO/IEC-646

• iso_dk, iso_fi – aliases for iso_no and iso_se respectively

• iso15 – ISO 8859-15

• latin0, latin9, iso8859_15 – aliases for iso15

• msx_intl, msx_jp, msx_ru, msx_br – MSX character encoding, International, Japanese, Russian and Brazilian respectively

• msx_us, msx_uk, msx_fr, msx_de – aliases for msx_intl

• atascii or atari – ATASCII as seen on Atari 8-bit computers

• atasciiscr or atariscr – screencodes used by Atari 8-bit computers

• koi7n2 or short_koi – KOI-7 N2

• vectrex – built-in Vectrex font

• utf8 – UTF-8

• utf16be, utf16le – UTF-16BE and UTF-16LE

When programming for Commodore, use pet for strings you're printing using standard I/O routines and petscr for strings you're copying to screen memory directly.

Escape sequences

Escape sequences allow for including characters in the string literals that would be otherwise impossible to type.

Some escape sequences may expand to multiple characters. For example, in several encodings {n} expands to {x0D}{x0A}.

Available everywhere

• {q} – double quote symbol

• {x00}–{xff} – a character of the given hexadecimal value

• {copyright_year} – this expands to the current year in digits

• {program_name} – this expands to the name of the output file without the file extension

• {program_name_upper} – the same, but uppercased

• {nullchar} – the null terminator for strings ("{nullchar}" is equivalent to ""z).
  The exact value of {nullchar} is encoding-dependent:

  • in the vectrex encoding it's {x80},
  • in the zx80 encoding it's {x01},
  • in the zx81 encoding it's {x0b},
  • in the petscr and petscrjp encodings it's {xe0},
  • in the atasciiscr encoding it's {xdb},
  • in the utf16be and utf16le encodings it's exceptionally two bytes: {x00}{x00}
  • in other encodings it's {x00} (this may be a subject to change in future versions).

Available only in some encodings

• {apos} – apostrophe/single quote (available everywhere except for zx80 and zx81)

• {n} – new line

• {b} – backspace

• {lbrace}, {rbrace} – opening and closing curly brace (only in encodings that support braces)

• {up}, {down}, {left}, {right} – control codes for moving the cursor

• {white}, {black}, {red}, {green}, {blue}, {cyan}, {yellow}, {purple} – control codes for changing the text color

• {bgwhite}, {bgblack}, {bgred}, {bggreen}, {bgblue}, {bgcyan}, {bgyellow}, {bgpurple} – control codes for changing the text background color

• {reverse}, {reverseoff} – inverted mode on/off

• {yen}, {pound}, {cent}, {euro}, {copy} – yen symbol, pound symbol, cent symbol, euro symbol, copyright symbol

• {u0000}–{u1fffff} – Unicode codepoint (available in UTF encodings only)

Character availability

Encoding	lowercase letters	backslash	currencies	intl	card suits
pet,	yes¹	no	£	none	yes¹
origpet	yes¹	yes		none	yes¹
oldpet	yes²	yes		none	yes²
petscr	yes¹	no	£	none	yes¹
petjp	no	no	¥	katakana³	yes³
petscrjp	no	no	¥	katakana³	yes³
sinclair, bbc	yes	yes	£	none	no
zx80, zx81	no	no	£	none	no
apple2	no	yes		none	no
atascii	yes	yes		none	yes
atasciiscr	yes	yes		none	yes
jis	yes	no	¥	both kana	no
iso15	yes	yes	€¢£¥	Western	no
msx_intl,msx_br	yes	yes	¢£¥	Western	yes
msx_jp	yes	no	¥	katakana	yes
msx_ru	yes	yes		Russian⁴	yes
koi7n2	no	yes		Russian⁵	no
vectrex	no	yes		none	no
utf*	yes	yes	all	all	yes
all the rest	yes	yes		none	no

1. pet, origpet and petscr cannot display card suit symbols and lowercase letters at the same time. Card suit symbols are only available in graphics mode, in which lowercase letters are displayed as uppercase and uppercase letters are displayed as symbols.

2. oldpet cannot display card suit symbols and lowercase letters at the same time. Card suit symbols are only available in graphics mode, in which lowercase letters are displayed as symbols.

3. petjp and petscrjp cannot display card suit symbols and katakana at the same time. Card suit symbols are only available in graphics mode, in which katakana is displayed as symbols.

4. Letter Ё and uppercase Ъ are not available.

5. Only uppercase. Letters Ё and Ъ are not available.

If the encoding does not support lowercase letters (e.g. apple2, petjp, petscrjp, koi7n2, vectrex), then text and character literals containing lowercase letters are automatically converted to uppercase. Only unaccented Latin and Cyrillic letters will be converted as such. Accented Latin letters will not be converted and will fail to compile without -flenient-encoding.
To detect if your default encoding does not support lowercase letters, test 'A' == 'a'.

Escape sequence availability

Encoding	new line	braces	backspace	cursor movement	text colour	reverse	background colour
pet,petjp	yes	no	no	yes	yes	yes	no
origpet	yes	no	no	yes	no	yes	no
oldpet	yes	no	no	yes	no	yes	no
petscr, petscrjp	no	no	no	no	no	no	no
sinclair	yes	yes	no	yes	yes	yes	yes
zx80,zx81	yes	no	yes	yes	no	no	no
ascii, iso_*	yes	yes	yes	no	no	no	no
iso15	yes	yes	yes	no	no	no	no
apple2	no	yes	no	no	no	no	no
atascii	yes	no	yes	yes	no	no	no
atasciiscr	no	no	no	no	no	no	no
msx_*	yes	yes	yes	yes	no	no	no
koi7n2	yes	no	yes	no	no	no	no
vectrex	no	no	no	no	no	no	no
utf*	yes	yes	yes	no	no	no	no
all the rest	yes	yes	no	no	no	no	no