Amiga memory map
Standard amount of memory in the Amiga
| Model | Chip RAM | Fast RAM | Kickstart ROM |
|---|---|---|---|
| Amiga 1000 | 256KB | None | 256KB |
| Amiga 500 | 512KB | None | 256KB |
| Amiga 500+ | 1MB | None | 512KB |
| Amiga 2000 | 512KB, later 1MB | None | 256KB |
| Amiga 3000 | 1-2MB | 1MB | 512KB |
| Amiga 600 | 1MB | None | 512KB |
| Amiga 1200 | 2MB | None | 512KB |
| Amiga 4000 | 2MB | 2-4MB | 512KB |
Memory map
Note: Models that are based on the same map are not listed, e.g. CDTV is based on A500 architecture, and the A1500 & A2500 are variations on the A2000. 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 & I/O registers | Reserved | ||||
| A80000-B7FFFF | 1024KB | Reserved | Additional system ROM space | Additional system ROM space (FMV ROM on CD32) | Reserved | ||||
| B80000-BEFFFF | 448KB | 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-D8FFFF | 64KB | Reserved | Reserved | Reserved (Real time clock on early A2000s) | Reserved | Reserved (Selected by SPARE_CS) | Clock Port (Selected by SPARE_CS) | Reserved | |
| D90000-D9FFFF | 64KB | Reserved | Reserved (Selected by NET_CS) | Reserved | |||||
| DA0000-DBFFFF | 128KB | Reserved | IDE controller | Reserved | |||||
| DC0000-DCFFFF | 64KB | Real Time Clock | Real time clock (RTC) | ||||||
| DD0000-DD0FFF | 4KB | Reserved | Reserved | SCSI controller | SCSI controller | ||||
| DD1000-DD3FFF | 12KB | IDE controller | |||||||
| DD4000-DDFFFF | 48KB | Reserved | |||||||
| DE0000-DFEFFF | 124KB | Mainboard resources | |||||||
| DFF000-DFFFFF | 4KB | 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 (various editions)
- M68000 Programmer's Reference Manual (1984, fourth edition)
- amiga-hardware.com (for standard amount of memory)
- Gayle, Gary specifications
- A1200 functional specification
