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Color Computer 2 Memory Map

From CoCopedia - The Tandy/Radio Shack Color Computer Wiki
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Overview

Start address End address Size (KB) Contents
0000 03FF 1 System Use
0400 05FF 0.5 Text screen memory
0600 0DFF 2 Disk System RAM
0E00 7FFF 30.5 Free RAM (depending on use of graphics pages)
0E00 25FF 4.5 Hires graphics page 1 (disk systems)
2600 3DFF 4.5 Hires graphics page 2 (disk systems)
8000 9FFF 8 Extended BASIC ROM
A000 BFFF 8 COLOR BASIC ROM
C000 DFFF 8 Cartridge ROM
C000 D800 6 Disk BASIC ROM
E000 FEFF 7.75 Unused
FF00 FFFF 0.25 Input/Output Area

Graphics page areas on cassette based systems:

Start address End address Size (KB) Contents
0600 1DFF 4.5 Hires graphics page 1 (cassette systems)
1E00 35FF 4.5 Hires graphics page 2 (cassette systems)

System Use

coming soon...

Input/Output Area

Start address End address Contents / Function
FF00 FF1F Peripheral Interface Adapter (PIA) 0
FF00 PIA0 data port A: Keyboard rows & joystick button
FF01 PIA0 control port A: Horizontal sync & interrupt control
FF02 PIA0 data port B: Keyboard columns
FF03 PIA0 control port B: Vertical sync control
FF04 FF1F PIA0 mirrors
FF20 FF3F Peripheral Interface Adapter (PIA) 1
FF20 PIA1 data port A: sound/cassette/RS-232 output/input
FF21 PIA1 control port A: Cassette motor control
FF22 PIA1 data port B: VDG control
FF23 PIA1 control port B: FIRQ & sound control
FF24 FF3F PIA1 mirrors
FF40 FF5F Diskette I/O usage
FF60 FF7F Miscellaneous external hardware control
FF80 FFBF Unused in CoCo 1 & 2
FFC0 FFDF SAM registers (screen mode & offset)
FFE0 FFF1 Reserved
FFF2 FFFF Interrupt vectors