Product specifications

Register 7 This register is split into two nibbles ie two 4 bit values.
The upper 4 bits 7,6,5 and 4, contain the colour code of the ink colour for
characters in text mode.
The lower 4 bits 3,2,1 and 0, contain the colour code of the paper colour
for characters in text mode and the backdrop (border) colour in all
modes.
Graphics Mode 2
2.4
Graphics 2 mode is the normal BASIC graphics mode. The features which it provides
are summarised in the table below.
Screen 768 unique characters (24 rows by 32 columns). 256 (Horizontal) by 192
(Vertical) plottable pixels.
15 colours (See appendix C) plus transparent, in a 3 (Vertical) by 2
(Horizontal) colour matrix for each character.
15 border (Backdrop) colours plus transparent.
Sprites 32 sprites each one of which may have any one of 15 colours including
transparent and are plottable at. any of the 256 times 192 screen pixel
positions.
256 patterns for 8 pixel by 8 pixel sprites. Bits 1. and 0 in VDP write-only
register 1 are both 0.
64 patterns for 16 pixel by 16 pixel sprites. Bits
1 and 0 in VDP write only register 1 are 1 and 0 respectively.
The VDP is in graphics 2 mode when mode bits M1 = 0,M2 = 0 and M3 = 1 (see
section 2.2 register 1 bits 3 and 4).
When the DP is first initialised into graphics two mode, the VRAM is organised as
displayed in the table below.
VRAM sub block Length in bytes
Pattern generator table 6144
Pattern colour table 6144
Pattern name table (screen) 768
Sprite attribute table 128
Sprite generator table 2048
If you had created your own graphic 2 mode set up then these tables could be located
at various addresses. If however, you had set them up at the same addresses as
BASIC does, then the VRAM memory map for these tables would look like that below.