Chris Collins

Tools · retro

Retro disk and tape images

One toolkit for retro disk and tape images — Amiga ADF, C64 D64/D71/D81/T64/TAP, Atari ATR and ST/MSA, Amstrad CPC and Spectrum +3 DSK, ZX TAP/TZX, BBC SSD/DSD, Apple II DOS 3.3 and ProDOS, MSX and PC FAT — auto-detected; browse, view files as hex, text in the machine's own character set, listed BASIC or pictures; add, delete and rename; create blank disks, convert, and open them in the emulators.

Added

Works with

How to use it

Drop a disk or tape image on the page, or tap to choose one. Nothing is uploaded: the image is read and changed in your browser, and the one you have open is kept in this browser (IndexedDB) so a reload brings it back. Download saves your copy; Close forgets it.

How to use it

  • Open works out what the image is from its contents (signatures, boot sectors, catalogue sanity checks), not just its name. When an image could be more than one thing — a FAT disk that might be MSX or PC, an Apple disk in DOS or ProDOS sector order — Open as lists the other readings with their scores. A ZIP holding images opens the image inside; .adz and .gz are unpacked first. Amiga LHA, LZX and DMS archives go to the archive extractor rather than being unpacked twice.

  • Disk shows what the file system knows: disk name and ID, DOS version, geometry, free space, boot options, container details (MSA, extended DSK, 2MG).

  • Files lists everything with its type, load address, protection bits and date where the format has them. Tap a file to open it:

    • Hex, with the C64 load address (or the file’s own load address) as the left column.

    • Text in a character set you choose — PETSCII upper or lower case, ATASCII, Amiga Latin-1 with ANSI codes removed, ZX Spectrum (£, ©, block graphics and UDGs), Apple II high-bit ASCII, BBC, CPC, MSX — remembered per machine.

    • BASIC, detokenised: Commodore BASIC V2 (through the C64 BASIC tool’s detokeniser) and Atari BASIC (Atari BASIC tool), plus Sinclair, BBC BASIC, Locomotive BASIC, MSX-BASIC and Applesoft.

    • Picture for Koala and Art Studio (C64), SCREEN$ (Spectrum), Micro Painter (Atari 8-bit), MSX Screen 2, Degas / NEOchrome (ST) and IFF ILBM, drawn by the retro image converter's decoders; Download PNG saves it.

  • Add files… writes into the open image (or the folder you tapped). The fields beside it are the format’s own: C64 file type, ZX start address, BBC load and exec addresses, Apple type and address, AMSDOS or +3DOS header. A .bas or .txt listing (lines starting with numbers) is tokenised for the machine first, so it LOADs and RUNs. Rename and Delete are on each file; tapes also have ↑ ↓ to reorder.

  • New blank image formats an empty disk for any format below — D64, D71, D81, T64, C64 and ZX TAP, ATR single or double density, ADF OFS or FFS, ST/MSA, CPC data or system, +3, SSD, DSD, DOS 3.3, ProDOS 140 KB or 800 KB, MSX and PC FAT.

  • Convert copies the files into another format for the same machine — D64 ⇄ D71 ⇄ D81 ⇄ T64 ⇄ TAP, ZX TAP ⇄ +3 disk (with +3DOS headers made from the tape headers), DOS 3.3 ⇄ ProDOS, SSD ⇄ DSD, CPC data ⇄ system, OFS ⇄ FFS — or changes the container without touching the sectors (ST ⇄ MSA, TZX → TAP, Apple DOS order ⇄ ProDOS order).

  • ▶ emulator opens the image in the site’s C64, Atari 8-bit, Atari ST, ZX Spectrum or Amiga emulator, in a new tab. A C64 PRG or an Atari executable can be run straight from the file view.

  • Extract all (ZIP) keeps folder paths and gives files a sensible extension (.prg, .seq, .bas, .bin).

Formats

Machine Images File system

Amiga

ADF, ADZ

AmigaDOS OFS / FFS (INTL), through the ADF explorer's module; delete and rename added here

Commodore 64 / 128

D64 (35 and 40 tracks, error bytes), D71, D81, T64, TAP

CBM DOS; TAP is decoded from the Kernal ROM loader’s pulses

Atari 8-bit

ATR, XFD

Atari DOS 2.0S / 2.5, MyDOS (read); writing for DOS 2 single and double density

Atari ST

ST, MSA

GEMDOS FAT12

Amstrad CPC

DSK (standard and extended)

AMSDOS / CP/M 2.2 data and system formats, AMSDOS headers

Spectrum +3

DSK

+3DOS (CP/M), PLUS3DOS headers, the disk specification sector

ZX Spectrum

TAP; TZX (read)

ROM tape headers: Program, Code, arrays, headerless blocks

BBC Micro

SSD, DSD

Acorn DFS, both sides of a DSD, Compact

Apple II

DSK, DO, PO, 2MG

DOS 3.3 and ProDOS (folders, seedling / sapling / tree files), either sector order

MSX

DSK

MSX-DOS FAT12, also disks with no BPB (geometry from the media byte)

PC

IMG, IMA, VFD

FAT12 and FAT16 with folders and long names (read)

Limits

  • Copy-protected images that need track timing (STX, IPF, G64, NIB, WOZ, EDSK weak sectors) are not read; nor is FAT32.

  • C64 TAP: only blocks in the standard Kernal ROM loader format are decoded — turbo loaders show up as nothing. Adding, deleting or renaming re-encodes the whole tape with standard timing. SEQ files on tape are not decoded.

  • TZX opens read-only (convert it to TAP to edit); direct-recording and CSW blocks are skipped.

  • Atari ST disks with copy protection or a non-standard boot sector may not have a usable BPB. DOS 2.5 enhanced density and MyDOS disks open read-only.

  • Files added to a CP/M (CPC / +3) disk without a header are padded to 128-byte records with ^Z, as CP/M itself does; the exact length is lost.

  • Blank DOS 3.3 and SYSTEM-format CPC disks have no DOS or CP/M on their system tracks, so they don’t boot — they are data disks. DOS 3.3 keeps tracks 0–2 reserved for the DOS image.

  • Long FAT file names are shown but new files get 8.3 names; renaming drops the long name.

Layouts are from the published references: Peter Schepers' D64/D71/D81/T64/TAP notes and the 1541/1571/1581 user’s guides; Beneath Apple DOS and Beneath Apple ProDOS; the CPCEMU and extended DSK specifications and the CPC 6128 manual; the Spectrum +3 manual (chapter 8) and The Complete Spectrum ROM Disassembly; the Acorn DFS user guide and the BBC Micro User Guide (BBC BASIC tokens); the MSX Red Book; Microsoft’s FAT specification; the Applesoft II reference manual. The code is in retro-disk.js and retro-basic.js, which the emulator pages can load to look inside disks too.

Linking to an example

Share link copies a link that opens the example you have open (your own images never go into a link). Write one by hand with example:

Parameter Meaning

example

c64, c64tape, zx, plus3, cpc, bbc, apple, prodos, atari, st, amiga, msx or pc

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