8-bit character set
The TRS-80 computer manufactured by Tandy / Radio Shack contains an 8-bit character set.[1] It is partially derived from ASCII, and shares the code points from 32 - 95 on the standard model. Code points 96 - 127 are supported on models that have been fitted with a lower-case upgrade.
The character set consists of letters, various numeric and special characters[1] as well as 64 semigraphics called squots (square dots) from a 2×3 matrix.[3] These were located at code points 128 to 191 with bits 5-0 following their binary representation,[3] similar to alpha-mosaic characters in World System Teletext.[4][5] These characters were used for graphics in games, such as Android Nim.
Character set
The following table shows the TRS-80 model I character set. Each character is shown with a potential Unicode equivalent. Space and control characters are represented by the abbreviations for their names.
- ^ Backspace and erase current character
- ^ Cursor on
- ^ Cursor off
- ^ Toggles Katakana characters (Model III)
- ^ Converts to wide 32 column mode
- ^ Backspace ← Cursor
- ^ Advance → Cursor
- ^ Downward ↓ linefeed
- ^ Upward ↑ linefeed
- ^ Move cursor to (0,0), also turns off 32 column mode
- ^ Move to start of line
- ^ Erase to end of line
- ^ Erase to end of frame
- ^ 192 to 255 are "Space Compression Codes", tabs for 0 to 63 spaces
References
Citations
- ^ a b Fylstra, Dan (April 1978). "Radio Shack TRS-80: An Owner's Report" (PDF). BYTE. Boston, MA, USA: BYTE Publications Inc.: 49–59. Archived (PDF) from the original on 2017-07-29. Retrieved 2017-07-29.
- ^ a b c Goldklang, Ira (2015). "Graphic Tips & Tricks". Archived from the original on 2017-07-29. Retrieved 2017-07-29.
- ^ Wiels. "TeleText - Het Protocol" (in Dutch). Mosaic characters. Archived from the original on 2017-12-22. Retrieved 2017-12-21.
- ^ "ETS 300 706 - Graphics Character Sets" (PDF).
- ^ Level II Basic Manual. Tandy / Radio Shack. 1978. pp. C1/C2.
- ^ "TRSM1ICH.TXT" (PDF), L2/19-025: Proposal to add characters from legacy computers and teletext to the UCS, 2019-01-04
Sources
- Heiserman, David L. (1983). Computer art and animation for the TRS-80. Prentice-Hall. ISBN 978-0-131-64749-7.
- Crawford, Chris (2003). Chris Crawford on Game Design. New Riders. ISBN 978-0-131-46099-7.
Further reading
- Bettencourt, Rebecca G. (2017) [2015]. "The Ultimate TRS-80 Font". Kreative Korporation. Archived from the original on 2017-07-29. Retrieved 2017-07-29.