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Settings

Regenerator 2000 has two types of settings (like most modern editors):

  • Settings
  • Document Settings

Program Settings

The Settings dialog allows you to configure global preferences for the application. It can be accessed via File -> Settings or using the shortcut Alt+P or Ctrl+,.

┌ Settings ----------------------------------------┐
│                                                  │
│  [X] Sync Blocks View                            │
│  [X] Sync Hex Dump View                          │
│  [ ] Sync Sprites View                           │
│  [ ] Sync Charset View                           │
│  [ ] Sync Bitmap View                            │
│                                                  │
│  [X] Open the latest file on startup             │
│  [X] Default is Unexplored (for new files)       │
│  [X] Check for updates                           │
│                                                  │
│  Entropy Warning Threshold: < 7.5 >              │
│                                                  │
│  Theme: < Dracula >                              │
│                                                  │
└──────────────────────────────────────────────────┘

Options

Sync View Options

The following options control whether different views automatically synchronize their cursor with the main Disassembly View. When enabled, navigating in the Disassembly View will update the others to show the corresponding memory location. Listed in keyboard shortcut order (Ctrl+1 through Ctrl+5).

  1. Sync Blocks View (Ctrl+1): Synchronizes the Blocks view.
  2. Sync Hex Dump View (Ctrl+2): Synchronizes the Hex Dump view.
  3. Sync Sprites View (Ctrl+3): Synchronizes the Sprites view.
  4. Sync Charset View (Ctrl+4): Synchronizes the Charset view.
  5. Sync Bitmap View (Ctrl+5): Synchronizes the Bitmap view.

General Options

  1. Open the latest file on startup

  2. When enabled, the application will automatically open the last project you were working on when it starts up. This allows you to quickly resume your work.

  3. Default is Unexplored (for new files)

  4. When enabled, newly loaded files will treat all memory regions as Undefined/Unexplored rather than assuming they are Code. This is useful when you want to start disassembly from scratch without any automatic assumptions.

  5. Check for updates

  6. When enabled, the application checks for new releases on startup and displays the latest available version in the top-right corner if an update is available.

Advanced Options

  1. Entropy Warning Threshold

  2. Sets the Shannon entropy value above which the entire binary file is flagged as potentially encrypted or compressed during initial load. Use Left/Right to decrease/increase the value in 0.1 increments (range 0.0–8.0).

  3. Theme

    • Allows you to choose the visual theme of the application. There are 9 built-in themes available. You can change themes in two ways:

      • Quick cycle: Press Left/Right to cycle through themes with instant live preview.
      • Full list: Press Enter to open the theme selector popup and pick from the list.

      Available themes: Solarized Dark, Solarized Light, Dracula (default), Gruvbox Dark, Gruvbox Light, Monokai, Nord, Catppuccin Mocha, Catppuccin Latte. See Themes for screenshots and details.

Document Settings

You can customize how Regenerator 2000 analyzes the binary and exports the code by accessing the Document Settings dialog (Shortcut: Alt+D or Ctrl+Shift+D).

┌ Document Settings ─────────────────────────────────────────────────────┐
│                                                                        │
│  [ ] Display External Labels at top                                    │
│  [x] Preserve long bytes (@w, +2, .abs, etc)                           │
│  [x] BRK single byte                                                   │
│  [ ] Patch BRK                                                         │
│  [ ] Use Illegal Opcodes                                               │
│  [x] Auto-generate Labels & Cross-refs                                 │
│                                                                        │
│  Description:                                                          │
│  (empty)                                                               │
│                                                                        │
│  Max X-Refs: < 5 >                                                     │
│  Arrow Columns: < 6 >                                                  │
│  Text Line Limit: < 40 >                                               │
│  Words/Addrs per line: < 5 >                                           │
│  Bytes per line: < 8 >                                                 │
│  Fill run threshold: < 8 >                                             │
│  Assembler: < 64tass >                                                 │
│  Target System: < Commodore 64 >                                       │
│  System Labels:                                                        │
│    [x] KERNAL                                                          │
│    [ ] BASIC                                                           │
│    [ ] I/O                                                             │
│  [x] Exclude well-known addresses from symbolic analysis               │
│  [x] Show system comments                                              │
│                                                                        │
└────────────────────────────────────────────────────────────────────────┘

Note

The System Labels, Exclude well-known addresses, and Show system comments options are system-dependent and only appear when the selected system provides the corresponding data.

Options

  1. Display External Labels at top

  2. Description: If enabled, generates labels, including external labels in the disassembly view. The exported file will contain all labels, regardless of this option.

  3. Preserve long bytes

  4. Description: Ensures that instructions using absolute addressing (3 bytes) are not optimized by the assembler into zero-page addressing (2 bytes) upon re-assembly. It adds prefixes like @w, +2, or .abs depending on the selected assembler to maintain the exact byte count of the original binary.

     This is useful to preserve the original byte count of the binary, for example, when disassembling a binary that
 contains absolute addresses.

  5. BRK single byte

  6. Description: Treats the BRK instruction as a 1-byte instruction. By default, this is enabled as most C64 code historically used BRK as a 1-byte instruction in practice, even though the 6502 architecture technically treats it as a 2-byte instruction (the instruction itself followed by a padding/signature byte). Disable this if your code specifically relies on the 2nd byte after a BRK.

    When "BRK single byte" is enabled, it gets represented as:

    ; These bytes will be diassembled as:
; $00, $00, $00, $00
; Each BRK consumes only one byte
$c000   brk
$c001   brk
$c002   brk
$c003   brk

  7. Patch BRK

  8. Description: If BRK single byte is disabled, this option ensures that the exported assembly code correctly includes the padding byte after BRK, preserving the original program structure on assemblers that might otherwise treat BRK as a single byte.
  9. Notice that not all assemblers support the "Patch BRK" disabled.

  10. This option is disabled (greyed out) when BRK single byte is enabled, or when the assembler is KickAssembler or ca65.

    When "Patch BRK" is enabled, it gets represented as:

    ; These bytes will be diassembled as:
; $00, $00, $00, $00
; Each BRK consumes two bytes (BRK + byte data)
$c000   brk
$c001   .byte $00
$c002   brk
$c003   .byte $00

    When "Patch BRK" is disabled, it gets represented as:

    ; These bytes will be diassembled as:
; $00, $00, $00, $00
; Each BRK consumes two bytes
$c000   brk #$00
$c002   brk #$00

  11. Use Illegal Opcodes

  12. Description: Enables the disassembler to recognize and decode undocumented (illegal) opcodes. If disabled, these bytes will be treated as data.

     When "Use Illegal Opcodes" is disabled, the disassembly might look like the following:

 ```asm
 sei
 .byte $ab        ; Invalid or partial instruction
 brk
 .byte $8e
 jsr $8ed0
 and ($d0,x)
 lda $d012        ; Raster Position
 cmp #$60
 bne $0816
 ldy #$00
 .byte $bf        ; Invalid or partial instruction
 brk
 .byte $09
 stx $d020        ; Border Color
 lda #$04
 sta $02
 .byte $c7        ; Invalid or partial instruction
 .byte $02        ; Invalid or partial instruction
 bne $0829
 .byte $8f        ; Invalid or partial instruction
 brk
 .byte $04
 iny
 cpy #$28
 bne $081f
 lda #$80
 .byte $0b        ; Invalid or partial instruction
 .byte $ff        ; Invalid or partial instruction
 bcc $083e
 jmp $0816
 inc $d020        ; Border Color
 jmp $083e
 ```

 When "Use Illegal Opcodes" is enabled, the disassembly might look like the following:

 ```asm
 sei
 lax #$00
 stx $d020        ; Border Color
 stx $d021        ; Background Color 0
 lda $d012        ; x-ref: $081b, $083b; Raster Position
 cmp #$60
 bne $0816
 ldy #$00
 lax $0900,y      ; x-ref: $0833
 stx $d020        ; Border Color
 lda #$04
 sta a_0002
 dcp a_0002          ; x-ref: $082b
 bne $0829
 sax $0400
 iny
 cpy #$28
 bne $081f
 lda #$80
 anc #$ff
 bcc $083e
 jmp $0816
 inc $d020        ; x-ref: $0839, $0841; Border Color
 jmp $083e
 ```

  13. Auto-generate Labels & Cross-refs

  14. Description: When enabled, the application will automatically perform a code analysis to generate auto-labels, cross-references, and other analysis data when the project is loaded or as needed.

  15. Description

  16. Description: A short free-form description or note for this document/binary. Press Enter to start editing; press Enter again to save or Esc to cancel.

  17. Max X-Refs

  18. Description: The maximum number of Cross-References (addresses that call/jump to a location) to display in the side comments for any given line.

  19. Arrow Columns

  20. Description: The number of character columns reserved on the left side of the disassembly view for drawing control flow arrows (branches and jumps). Increasing this can make complex control flow easier to read.

  21. Text Line Limit

    • Description: The maximum number of characters to display on a single line for Text block types before wrapping or truncating.

  22. Words/Addrs per line

    • Description: Controls how many 16-bit values (Words or Addresses) are displayed on a single line when using that Block Type. Range: 1-8.

  23. Bytes per line

    • Description: Controls how many 8-bit values (Bytes) are displayed on a single line when using the Byte Block Type. Range: 1-40.

  24. Fill run threshold

    • Description: When a Byte block contains a run of N or more consecutive identical bytes, the disassembler automatically collapses the entire run into a single assembler fill directive instead of emitting one .byte per value. Set to 0 to disable the optimization entirely (default: 8).

      The directive name varies by assembler:

      Assembler Directive syntax
      64tass .fill count, value
      ACME !fill count, value
      KickAssembler .fill count, value
      ca65 .res count, value

      Example — 16 consecutive $00 bytes (64tass format):

      ; Without fill run threshold (or threshold > 16):
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00

; With fill run threshold <= 16:
.fill 16, $00

      Runs are only coalesced within a single Byte block. A label, cross-reference, splitter, or comment mid-block will break the run at that boundary.

  25. Assembler

    • Description: Selects the target assembler syntax for export. Supported assemblers include 64tass, ACME, KickAssembler, and ca65. Changing this updates the syntax used in the disassembly view to match the target. Press Enter to open the assembler selector popup, or use Left/Right to cycle.

  26. Target System

    • Description: Defines the target hardware system (e.g., Commodore 64). This helps the analyzer identify system-specific memory maps, hardware registers (like VIC-II or SID), and ROM routines. Press Enter to open the system selector popup, or use Left/Right to cycle. Changing the system resets the enabled System Labels features.

  27. System Labels (system-dependent)

    • Description: A group of checkboxes that control which system label sets are loaded for the current system. For example, on the Commodore 64 the available sets include KERNAL, BASIC, I/O, etc. Each set provides pre-defined labels for well-known addresses (ROM entry points, hardware registers, etc.). Toggle a set with Space or Enter. The available sets depend on the selected System.

  28. Exclude well-known addresses from symbolic analysis (system-dependent)

    • Description: When enabled, addresses that are covered by the system's system label definitions are excluded from the analyzer's code-walking pass. This prevents the analyzer from chasing into ROM routines or hardware registers, which can reduce false positives in the disassembly. Only appears for systems that define excluded address ranges in their system config.

  29. Show system comments (system-dependent)

    • Description: When enabled, pre-defined system comments (e.g. hardware register descriptions like "Border Color" for $D020 on the C64) are displayed as side comments in the disassembly view. Only appears for systems that include system comments in their system config.