Difference between revisions of "MODE 10"

From BeebWiki
Jump to: navigation, search
m (1 revision)
m (1 revision)
(No difference)

Revision as of 19:12, 8 March 2015

Demonstration of 'MODE 10' (BBC)

MODE 10 is the unofficial title of a low-resolution screen MODE, developed by Ian Robertson and published in The Micro User magazine (November 1985, p.123). It works on the BBC Micro but not the Electron or Master, or the Archimedes (where MODE 10 is officially a 256-colour version of MODE 2).

The MODE 10 code adapts the MODE 6 screen to provide a 20 × 25 text display in 4 colours. The MOS does not allow complete support of this MODE and some bugs can be seen: for instance, text windows do not work correctly.

'MODE 10'
Type Bitmapped, text only ('ASCII')
Resolution Text 20 × 25 characters
Graphics n/a
Character size 8 × 10 pixels, top 8 lines user definable
Pixel aspect 2:1 (wide)
Bits per pixel 2
Default palette Logical colour Actual colour
0 0 (black)
1 1 (red)
2 3 (yellow)
3 7 (white)
Memory allocated 8192 bytes
on screen 8000 bytes
Address range Model B etc. &6000..&7FFF
Configuration Video ULA control register &84
Video ULA palette register file &07 &17 &26 &36
&47 &57 &66 &76
&84 &94 &A0 &B0
&C4 &D4 &E0 &F0
CRTC register file &3F &28 &31 &24
&1E &02 &19 &1B
&01 &09 &67 &09
(from table in MOS 1.20 at &C492..&C49D)

-- beardo 12:59, 20 September 2006 (BST)