HIGH-RESOLUTION TEXT SCREEN
Code for the example display above:
10 WIDTH 80 20 CLS 30 FOR I=0 TO 255 40 LPOKE &H6C000+(I*2),I:'CHARACTER VALUE 50 LPOKE &H6C000+(I*2)+1,I:'COLORS AND ATTRIBUTES 60 NEXT
COLORS AND ATTRIBUTES
When Bit Plane (BP) is zero, and Color Res (CRES) is one, then each character value in the high resolution text screen is followed by an attributes byte which is formatted like this:
| Bit 7 | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
|---|---|---|---|---|---|---|---|
| BLINK | UNDLN | FGND2 | FGND1 | FGND0 | BGND2 | BGND1 | BGND0 |
Foreground colors are controlled by GIME palette registers 8-15
Background colors are controlled by GIME palette registers 0-7
MEMORY
Super Extended Color BASIC locates the High Resolution Text Screen memory buffer on MMU page 36 by default, from extended memory addresses $6C000 - $6DFFF.
| TEXT RESOLUTION | CHARACTER RAM | COLOR ATTRIBUTES |
|---|---|---|
| 80 x 24 | 1920 bytes | 1920 bytes |
| 80 x 25 | 2000 bytes | 2000 bytes |
| 80 x 28 | 2240 bytes | 2240 bytes |
Even switching to 28-line per screen mode, there is more than enough memory in the 8192-byte MMU page for the text characters and color attribute bytes (if used).
SEE ALSO
Hi-Res Text Window by Trey Tomes
Hprint Font Editor by John Strong
RTS
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