Display
The ByteFrost uses a 2004A LCD display. This is a character LCD display with 4 rows and 20 columns.
Instead of interfacing with the display directly, an Arduino Nano is used to serve as a display card for the ByteFrost. This makes printing characters in assembly significantly easier, as well as implementing new characters not found in the 2004A's character set (such as a new-line). The Arduino code for the display card is available under the Display/ directory in the ByteFrost repository as Display.ino.
The character set of the display is somewhat similar to ASCII. However, there are major differences, such as 256 possible characters instead of the 128 in ASCII, and some repetitions of characters (courtesy of our display card). Interestingly, our 2004A model's character ROM includes a Katakana character set!
The character set of the display is given by the following two tables - the first shows our added characters (added via the display card), and the second is the 2004A's character set.
| Dec | Hx | Oct | Char |
|---|---|---|---|
| 0 | 0 | 000 | 0 |
| 1 | 1 | 001 | 1 |
| 2 | 2 | 002 | 2 |
| 3 | 3 | 003 | 3 |
| 4 | 4 | 004 | 4 |
| 5 | 5 | 005 | 5 |
| 6 | 6 | 006 | 6 |
| 7 | 7 | 007 | 7 |
| 8 | 8 | 010 | 8 |
| 9 | 9 | 011 | 9 |
| 10 | A | 012 | A |
| 11 | B | 013 | B |
| 12 | C | 014 | C |
| 13 | D | 015 | D |
| 14 | E | 016 | E |
| 15 | F | 017 | F |
| 16 | 10 | 020 |
\n (new-line) |
