MODE 1
MODE 1 is a medium-resolution screen MODE, introduced on the BBC Micro Model B and supported by the entire BBC series including the Archimedes. It allows colour graphics to be shown but leaves only 9 KB for programs -- even less if a disc interface or Econet is fitted.
| Type | Graphical ('ASCII') | |
| Resolution | Text | 40 × 32 characters |
| Graphics | 320 × 256 pixels | |
| Character size | 8 × 8 pixels, user definable | |
| Pixel aspect | 1:1 (square) | |
| Bits per pixel | 2 | |
| Default palette | Logical colour | Actual colour |
|---|---|---|
| 0 | 0 (black) | |
| 1 | 1 (red) | |
| 2 | 3 (yellow) | |
| 3 | 7 (white) | |
| Memory | allocated | 20480 bytes |
| on screen | 20480 bytes | |
| Address range | Model B etc. | &3000..&7FFF |
| Configuration | Video ULA control register | &D8 |
| Video ULA palette register file | &07 &17 &26 &36 &47 &57 &66 &76 &84 &94 &A0 &B0 &C4 &D4 &E0 &F0 | |
| CRTC register file | &7F &50 &62 &28 &26 &00 &20 &22 &01 &07 &67 &08 (from table in MOS 1.20 at &C46E..&C479) | |
-- beardo 14:10, 16 September 2006 (BST)
