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--- sd:appendix_3_memory_map [2026/02/25 02:46] – created appledog
+++ sd:appendix_3_memory_map [2026/02/25 04:32] (current) – appledog
@@ Line 4: / Line 4: @@
 == Memory Map
-### BANK 0 - User RAM & System Variables ($00,0000–$00,FFFF)
+=== BANK 0 - User RAM & System Variables ($00,0000–$00,FFFF)
-^ Address Range       ^ Size        ^ Name / Area                  ^ Description / Notes ^
+^ Address Range ^ Size ^ Name / Area ^ Description / Notes ^
-| $000000–$00EEFF      | 61,184 B    | User RAM                       | General purpose free RAM |
+| $000000–$00FFFF | 61,184 B | User RAM | General purpose free RAM |
-| $00F000–$00FFFF      | 4,096 B     | User RAM                       | Additional free RAM                                        |
+| $000100–$00FF00 | ~64 KB | BASIC Program Area | Main BASIC program storage (see int0x05h.sda) |
-| $000100–$00FF00      | ~64 KB      | BASIC Program Area             | Main BASIC program storage (see int0x05h.sda)              |
 **Total free in Bank 0:** ≈65,280 bytes
-### BANK 1 - KERNAL ROM & HARDWARE ($010000–$01FFFF)
+=== BANK 1 - KERNAL ROM & HARDWARE ($010000–$01FFFF)
-^ Address Range       ^ Size          ^ Name / Symbol                ^ Description / Notes                                                                 ^
+^ Address Range ^ Size ^ Name / Symbol ^ Description / Notes ^
-| $010000–$0100FF      | 256 bytes     | Kernal Bootstrap               | Reserved for boot code                                                                    |
+| $010000–$0100FF | 256 bytes | Kernal Bootstrap | Reserved for boot code |
-| $010100–$013FFF      | ~16 KB        | Kernal Code                    | Main KERNAL routines + limited expansion space                                            |
+| $010100–$013FFF | ~16 KB | Kernal Code | Main KERNAL routines + limited expansion space |
-| $014000–$01DBFF      | 40,960 bytes  | RESERVED                       | Reserved for future KERNAL expansion                                                      |
+| $014000–$01DBFF | 40,960 bytes | RESERVED | Reserved for future KERNAL expansion |
-| $01DB00–$01DBFF      | 256 bytes     | PATB_TBUF                      | ROM BASIC tokenizer scratch space (currently underused?)                                  |
+| $01DB00–$01DBFF | 256 bytes | PATB_TBUF | ROM BASIC tokenizer scratch space (currently underused?) |
-| $01DC00–$01DFFF      | 1,024 bytes   | Stack Space                    | Hardware stack (grows down from $01DFFF; overflow if SP < $01DC00)                        |
+| $01DC00–$01DFFF | 1,024 bytes | Stack Space | Hardware stack (grows down from $01DFFF; overflow if SP < $01DC00) |
-| $01E000–$01E7FF      | 2,048 bytes   | VM1_CHAR_ROM                   | PETSCII font data (copied from character ROM at initialization)                           |
+| $01E000–$01E7FF | 2,048 bytes | VM1_CHAR_ROM | PETSCII font data (copied from character ROM at initialization) |
-| $01E800–$01E8FF      | 256 bytes     | Kernal Workspace               | Reserved for KERNAL internal use                                                          |
+| $01E800–$01E8FF | 256 bytes | Kernal Workspace | Reserved for KERNAL internal use |
-| $01E900–$01EBFF      | 768 bytes     | INT_VECTOR_TABLE               | Interrupt vector table (256 vectors × 3 bytes = 24-bit addresses, little-endian)          |
+| $01E900–$01EBFF | 768 bytes | INT_VECTOR_TABLE | Interrupt vector table (256 vectors × 3 bytes = 24-bit addresses, little-endian) |
-| $01EC00–$01ECFF      | 256 bytes     | SCRATCH_BUFFER                 | General-purpose scratch space (used by INPUT, expression eval, parsing, etc.)             |
+| $01EC00–$01ECFF | 256 bytes | SCRATCH_BUFFER | General-purpose scratch space (used by INPUT, expression eval, parsing, etc.) |
-| $01ED00–$01EDFF      | 256 bytes     | INPUT_BUFFER                   | Input line buffer (also used as part of PATB system variables)                            |
+| $01ED00–$01EDFF | 256 bytes | INPUT_BUFFER | Input line buffer (also used as part of PATB system variables) |
-| $01EE00–$01EEFF      | 256 bytes     | PATB_VARIABLES + stacks etc.   | PATB_BASIC variables, expression stack, GOSUB/FOR stacks, program pointers…               |
+| $01EE00–$01EEFF | 256 bytes | PATB_VARIABLES + stacks etc. | PATB_BASIC variables, expression stack, GOSUB/FOR stacks, program pointers… |
-| $01EF00–$01EF0B      | 12 bytes      | Video System Registers         | VIDEO_MODE, VIDEO_COLUMNS, VIDEO_ROWS, VIDEO_CHAR_WIDTH/HEIGHT, VIDEO_CLOCK…              |
+| $01EF00–$01EF0B | 12 bytes | Video System Registers | VIDEO_MODE, VIDEO_COLUMNS, VIDEO_ROWS, VIDEO_CHAR_WIDTH/HEIGHT, VIDEO_CLOCK… |
-| $01EF0C–$01EF0F      | 4 bytes       | Cursor System                  | CURSOR_BLINK, CURSOR_STATE, CURSOR_X, CURSOR_Y                                            |
+| $01EF0C–$01EF0F | 4 bytes | Cursor System | CURSOR_BLINK, CURSOR_STATE, CURSOR_X, CURSOR_Y |
-| $01EF10–$01EF31      | 34 bytes      | Keyboard System                | KBD_STATUS_FLAGS, KEYBOARD_COUNT, KEYBOARD_BUFFER (32 bytes)                              |
+| $01EF10–$01EF31 | 34 bytes | Keyboard System | KBD_STATUS_FLAGS, KEYBOARD_COUNT, KEYBOARD_BUFFER (32 bytes) |
-| $01EF32–$01EF3A      | 9 bytes       | Input/Syscall System           | INPUT_MODE, INPUT_LENGTH, SYSCALL_STATUS/ADDR, KBPC (BASIC program counter)               |
+| $01EF32–$01EF3A | 9 bytes | Input/Syscall System | INPUT_MODE, INPUT_LENGTH, SYSCALL_STATUS/ADDR, KBPC (BASIC program counter) |
-| $01EF3B–$01EF42      | 8 bytes       | FREE                           | Reserved for future use                                                                   |
+| $01EF3B–$01EF42 | 8 bytes | FREE | Reserved for future use |
-| $01EF43–$01EF49      | 7 bytes       | Extended Video System          | VIDEO_COLOR_MODE, VIDEO_TEXT_BASE, VIDEO_COLOR_BASE                                       |
+| $01EF43–$01EF49 | 7 bytes | Extended Video System | VIDEO_COLOR_MODE, VIDEO_TEXT_BASE, VIDEO_COLOR_BASE |
-| $01EF4A–$01EF7F      | 54 bytes      | FREE                           | Reserved for hardware expansion                                                           |
+| $01EF4A–$01EF7F | 54 bytes | FREE | Reserved for hardware expansion |
-| $01EF80–$01EFBF      | 64 bytes      | Sound System (4 voices)        | 4 × SID-like voices (frequency, gate, ADSR, volume, etc.)                                 |
+| $01EF80–$01EFBF | 64 bytes | Sound System (4 voices) | see: [[Appendix 5 Sound System|SD-450 Sound System]] |
-| $01EFC0–$01EFFF      | 64 bytes      | FREE                           | Reserved for sound system expansion                                                       |
+| $01EFC0–$01EFFF | 64 bytes | FREE | Reserved for sound system expansion |
-| $01F000–$01F3E7      | 1,000 bytes   | VM1_TEXT_BASE                  | Video Mode 1 – 40×25 text character map                                                   |
+| $01F000–$01F3E7 | 1,000 bytes | VM1_TEXT_BASE | Video Mode 1 – 40×25 text character map |
-| $01F3E8–$01F7FF      | 1,048 bytes   | FREE (text area)               | —                                                                                         |
+| $01F3E8–$01F7FF | 1,048 bytes | FREE (text area) | — |
-| $01F800–$01FBE7      | 1,000 bytes   | VM1_COLOR_BASE                 | Video Mode 1 – 40×25 color attribute map                                                  |
+| $01F800–$01FBE7 | 1,000 bytes | VM1_COLOR_BASE | Video Mode 1 – 40×25 color attribute map |
-| $01FBE8–$01FFFF      | 1,048 bytes   | FREE (color area)              | —                                                                                         |
+| $01FBE8–$01FFFF | 1,048 bytes | FREE (color area) | — |
-### BANK 2 – USER RAM ($020000–$02FFFF)
+=== BANK 2 – USER RAM ($020000–$02FFFF)
-^ Address Range       ^ Size        ^ Name / Area      ^ Description ^
+^ Address Range ^ Size ^ Name / Area ^ Description ^
-| $020000–$02FFFF      | 65,536 B    | User RAM           | Completely free                                           |
+| $020000–$02FFFF | 65,536 B | User RAM | Completely free |
-### BANK 3 – USER RAM ($030000–$03FFFF)
+=== BANK 3 – USER RAM ($030000–$03FFFF)
-^ Address Range       ^ Size        ^ Name / Area      ^ Description ^
+^ Address Range ^ Size ^ Name / Area ^ Description ^
-| $030000–$03FFFF      ^ 65,536 B    | User RAM           | Completely free                                           |
+| $030000–$03FFFF ^ 65,536 B | User RAM | Completely free |
-### Quick Free Space Summary
+=== Quick Free Space Summary
-^ Bank   ^ Free Bytes     ^ Notes                              ^
+^ Bank ^ Free Bytes ^ Notes ^
-| 0      | 65,280        | Mostly user RAM + small BASIC area   |
+| 0 | 65,280 | Mostly user RAM + small BASIC area |
-| 1      | ~40,960       | Reserved for future KERNAL expansion |
+| 1 | ~40,960 | Reserved for future KERNAL expansion |
-| 2      | 65,536        | Completely free                      |
+| 2 | 65,536 | Completely free |
-| 3      | 65,536        | Completely free                      |
+| 3 | 65,536 | Completely free |
-| **Total** | **237,312** | Available for user programs & data   |
+| **Total** | **237,312** | Available for user programs & data |
-You can copy-paste the tables directly into a DokuWiki page. Let me know if you'd like any section split further, merged, or additional columns (e.g. read/write access, usage examples).