TRON code

Revision as of 04:43, 2 August 2022

This article describes the character encoding used in TRON. Unlike Unicode, it does not use the Han unification; it can clearly distinguish Japanese from Chinese texts.

Character codes are two byte codes and are split into four zones:

• A zone: High byte and low byte are both in range 0x21 to 0x7E.
• B zone: High byte in range 0x80 to 0xFD and low byte in range 0x21 to 0x7E.
• C zone: High byte in range 0x21 to 0x7E and low byte in range 0x80 to 0xFD.
• D zone: High byte and low byte are both in range 0x80 to 0xFD.

The character codes are grouped in planes; the language selection is by first byte 0xFE and then second byte makes the plane number added to 0x20 (for example, plane 1 is selection by code 0xFE21). The default plane (if not otherwise specified) is usually plane 1.

List of planes:

• 1 = JIS, GB2312, KS X 1001, and Braille
• 2,3 = GT
• 6 = Big5
• 8,9 = Dai-Kan-Wa-Jiten, hentaigana, etc
• 10 = Dongba symbols

Conversion other formats into TRON is described below.

Plane 1

JIS X 0208, and first plane of JIS X 0213:

hi = ku+0x20
lo = ten+0x20

JIS X 0212:

hi = ku+0xA0
lo = ten+0x20

Second plane of JIS X 0213:

hi = numbers 0x87 to 0xA0, contiguous by valid rows of JIS X 0213 (1,3-5,8,12-15,78-94)
lo = ten+0x20

GB 2312:

hi = ((ku-1)*94+ten-1)/126+0x21
lo = ((ku-1)*94+ten-1)%126+0x80

KS X 1001:

hi = ((ku-1)*94+ten-1)/126+0xB7
lo = ((ku-1)*94+ten-1)%126+0x80

Braille:

(unknown)

Plane 9

• Codes 0x9721 to 0x972A are the Chinese/Japanese numbers one to ten in the square.
• Codes 0x972B to 0x975A are the katakana in parentheses.
• Codes 0x975B to 0x9766 are the lowercase roman numbers i to xii in the circle.
• Codes 0x9767 to 0x977A are the numbers 1 to 20 in the triangle.

External resources

• Partially TRON plane 9 in GlyphWiki

Commentary

• A Message to GNU/Linux Hackers
• The Handling of Chinese Characters and TRON Code