3 RED 16 PINK
4 MAGENTA 17 PASTEL MAGENTA
5 MAUVE 18 BRIGHT GREEN
6 BRIGHT RED 19 SEA GREEN
7 PURPLE 20 BRIGHT CYAN
8 BRIGHT MAGENTA 21 LIME GREEN
9 GREEN 22 PASTEL GREEN
10 CYAN 23 PASTEL CYAN
11 SKY BLUE 24 BRIGHT YELLOW
12 YELLOW 25 PASTEL YELLOW
26 BRIGHT WHITE
1.4) Memory Map
The 64K of RAM is allocated as follows.
Note that part of the ROM overlays the screen RAM, thereby releasing the maximum possible area
to user RAM during BASIC operations.
0000H
ROM SECTION 0 <
3FFFH
4000H
7FFFH
8000H
BFFFH
C000H
ROM SECTION 1 <
> RAM [Screen 3]
FFFFH
When there is both RAM and ROM at an address, then READING accesses the ROM and WRITING
accesses the RAM. Either ROM section can be turned off,allowing read access to the RAM at the
same address.
1.5) Add-on ability
1.5.1) Sideways ROMS
Provision is made for additional ROMS to be selected in place of any part of the on-board ROM. The
address arbitration and bank selection logic will be contained in a module connected to the
expansion bus, but all the signals required are brought to the expansion bus.
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