CRTC

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register description
 0 - Horizontal total
 1 - Horizontal displayed characters
 2 - Horizontal sync position
 3 - Horizontal sync width/Vertical sync time
 4 - Vertical total
 5 - Vertical total adjust
 6 - Vertical displayed characters
 7 - Vertical sync position
 8 - Interlace/Display delay/Cursor delay
 9 - Scan lines per character
10 - Cursor start line and blink type
11 - Cursor end line
12 - Screen start address
13 - Screen start address
14 - Cursor position
15 - Cursor position
16 - Light pen position
17 - Light pen position
18 - Cursor width (BBFW)

Most systems without a hardware 6845 CRTC implement setting the cursor state with registers 10 and 11 via VDU 23;10 and VDU 23;11.


Jgharston 14:47, 24 December 2007 (UTC)