Amiga memory map

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Standard amount of memory in the Amiga

  • Amiga 1000 - 256KB chip RAM
  • Amiga 500 - 512KB chip RAM
  • Amiga 500+ - 1MB chip RAM
  • Amiga 2000 - 512KB chip RAM, later 1MB chip RAM
  • Amiga 3000 - 1-2MB chip RAM, 1MB fast RAM
  • Amiga 600 - 1MB chip RAM
  • Amiga 1200 - 2MB chip RAM
  • Amiga 4000 - 2MB chip RAM, 2-4MB fast RAM

Memory map

Note: Models that are based on the same map are not listed, e.g. CDTV is based on A500 architecture. Where differences exist they are specified in brackets.

Address Range Size Category Function
A1000 A500 / 2000 A500+ A600 A1200 A3000 A4000
000000-03FFFF 256KB Chip RAM First 256KB of chip RAM
040000-07FFFF 256KB 256KB chip RAM expansion card Second 256KB of chip RAM (to 512KB)
080000-0FFFFF 512KB Reserved 512KB chip RAM expansion card (A500 trapdoor) Second 512KB of chip RAM (to 1MB)
100000-1FFFFF 1MB Reserved 1MB chip RAM expansion card Second 1MB of chip RAM (to 2MB)
200000-5FFFFF 4MB Zorro-II space First 4 MB Auto-config space / Fast RAM
600000-9FFFFF 4MB Second 4 MB Auto-config space / Fast RAM PCMCIA memory card / Fast RAM Second 4 MB Auto-config space / Fast RAM
A00000-A7FFFF 512KB Reserved Reserved PCMCIA control registers Reserved
A80000-BEFFFF 1471KB Reserved
BF0000-BFFFFF 64KB CIAs 8520 CIAs and timers
C00000-C7FFFF 512KB Slow-fast RAM Reserved Pseudo-fast RAM Reserved Chip register shadow
C80000-CFFFFF 512KB Reserved for pseudo-fast RAM
D00000-D7FFFF 512KB Reserved
D80000-D9FFFF 128KB Reserved Reserved
DA0000-DBFFFF 128KB Reserved IDE controller Reserved
DC0000-DCFFFF 64KB Clock port Real time clock / Clock port
DD0000-DD0FFF 4KB Reserved Reserved SCSI controller SCSI controller
DD1000-DD3FFF 12KB IDE controller
DD4000-DDFFFF 48KB Reserved
DE0000-DEFFFF 64KB Custom chip registers and mainboard resources
DF0000-DFFFFF 64KB Custom chip registers
E00000-E7FFFF 512KB Reserved Reserved for first 512KB of 1MB system ROM Reserved
E80000-E8FFFF 64KB Auto-config space. Boards appear here before the system relocates them to their final address.
E90000-EFFFFF 448KB Secondary auto-config space (usually 64K I/O boards)
F00000-F7FFFF 512KB Extended ROM Reserved Extended ROM (CDTV) Reserved Flash ROM / Extended ROM (CD32) Diagnostic ROM
F80000-FBFFFF 256KB Kickstart ROM Reserved System ROM
FC0000-FFFFFF 256KB System ROM
32-bit Addresses
01000000 - 03FFFFFF 48MB Reserved N/A Reserved
04000000-06FFFFFF 48MB Fast RAM Reserved for motherboard RAM expansion
07000000-07FFFFFF 16MB Motherboard RAM
08000000-0FFFFFFF 128MB CPU slot expansion
10000000-7FFFFFFF 1792MB Zorro-III space Zorro-III expansion space
80000000-FEFFFFFF 2032MB Reserved Reserved
FF000000-FF00FFFF 64KB Zorro-III config space
FF010000-FFFFFFFF 16320KB Reserved

Note that various modifications and third party hardware can change the details of this map, particularly those expansions that add additional addressing capabilities, e.g. 32-bit accelerators in A1200s, 2MB chip RAM modifications in A500s etc.

Some special addresses:
* 000000-000100 - MC680x0 Exception Vector Assignment table  (if VBR=0)
* 000004        - Exec base (pointer to exec.library jumptable) 

Sources for this info

  • Amiga Hardware Reference Manual (1986)
  • M68000 Programmer's Reference Manual (1984,fourth edition)
  • (for standard amount of memory)