SUPPORTED FORMATS
SSD / DSD (Acorn DFS) · ADFS S / M / L / D / E / E+ / F / F+ · beeb.MMB (511-slot container) · HFE (Gotek / HxC) · Acorn File Server Level 2 / 3 · UEF (tape) · RFS (ROM filing system)

LOADING A DISK
Click 💾 OPEN above a panel, drag-and-drop a disk image file onto it, paste a direct download link with 🔗 URL, or search 🔍 bbcmicro.co.uk's game archive by name.

CREATING A NEW DISK
Click 💾 OPEN, then + NEW DISK. Choose a size for DFS/ADFS, or pick MMB / UEF / RFS from Other Formats. A blank RFS ROM includes a genuine working boot handler — see the UEF & RFS tab for details.

TWO DRIVES SIDE BY SIDE
Each panel is an independent drive. Load a different disk in each to copy files between them — drive 0's COPY button points right (→) toward drive 1, and drive 1's points left (←) toward drive 0.

SAVING YOUR WORK
Click ↓ SAVE above a panel to download the modified disk image, or ↓ HFE to download the disc as an HFE file for a Gotek or HxC floppy emulator (DFS, any ADFS floppy, or the current MMB disc). Nothing is saved automatically or kept on the server — download before you close the tab. See the ABOUT tab for what happens to uploaded files.

RUN IT
▶ RUN boots the disc in jsbeeb, a BBC Micro emulator in your browser (DFS on a BBC B, ADFS S/M/L on a Master 128). It opens a new tab with a copy of the disc as it is now; the link lasts two hours.

VIEWING & EDITING A FILE
Click VIEW (or double-click a row) to open a file. BASIC programs detokenise automatically; text files show as text; anything else shows as a hex dump you can edit directly. Extra read-only tabs: DISASM (6502 disassembly from the load address), MODE 7 for teletext screens, and SCREEN for MODE 0–6 screen dumps (the mode is guessed from the size and can be changed).

EDIT FILE DETAILS
Click EDIT to change a file's name, load/exec address, locked flag, and (ADFS only) readable/writable access and RISC OS filetype. For a typed ADFS file, LOAD ADDR/EXEC ADDR double as a filetype code and a timestamp — the FILETYPE dropdown and a live date picker handle the encoding for you; you don't need to work out the bit-packing by hand.

SELECTING & DELETING
Tick checkboxes or click rows (Shift/Ctrl-click for ranges) to select multiple files, then DEL to delete, or ATTR to set Locked/Readable/Writable on all of them at once. Locked files must be unlocked before they can be deleted or overwritten.

REORDERING & COMPACT
Drag a row onto another row within the same panel to reorder it — files are listed in physical disk order by default (earliest first), matching how COMPACT lays them out. COMPACT repacks all files with no gaps, in whatever order is currently shown, so dragging first lets you choose the final layout (useful for grouping frequently-used files to reduce head-seek time on real hardware). Available for DFS, MMB and every ADFS format (see the ADFS tab); RFS's flat catalogue has no equivalent.

EXPORTING FILES
Tick checkboxes, then click ↓ ZIP to download them as a ZIP with a .inf sidecar per file (preserving load/exec/locked for round-tripping through other tools). A single ticked file downloads directly.

COPYING BETWEEN DRIVES
Select file(s) and click COPY TO 0/1, or drag a row across to the other panel. A name clash offers Ignore, Replace or Rename (with "apply to all"), or Cancel to stop. Copying a folder (ADFS) recurses into its contents automatically.

IMPORTING A FILE OR ZIP
Click ↑ IMPORT and browse for a file or ZIP, or just drag-and-drop it onto a loaded panel. A .inf sidecar alongside a file (inside a ZIP, or dropped together) supplies its BBC attributes automatically; without one, load/exec default to &00000000.

LOADING A WHOLE DISK'S FILES INTO ANOTHER
Drop a disk image file onto an already-loaded panel and choose Import All Files to pull every file from it into the current disk, instead of replacing what's loaded.

URL IMPORT
Click 🔗 URL and paste a direct link to a disk image, or to a ZIP containing one — from any site. If the ZIP has more than one disk image, you'll be asked which one to load. Capped at 128MB, and the URL's host is checked to make sure it doesn't point at a private/internal address.

SEARCH BBCMICRO.CO.UK
Click 🔍 bbcmicro.co.uk to search the Complete BBC Micro Games Archive by title or publisher and load a result straight into a drive — no separate download needed. The game list is cached for a day so repeat searches are instant.

MAP TYPES
Old-map (S/M/L/D) uses a fixed 47-entry root catalogue, like DFS. New-map splits into Nick (E/F: fixed-size directories, up to 77 entries) and Big (E+/F+: directories grow to fit their contents, no fixed limit).

SUBDIRECTORIES
Double-click a folder row to enter it; the breadcrumb bar at the top lets you navigate back out. NEW DIR creates a subdirectory in the current location, in every ADFS format.

FILETYPE & DATE
A RISC OS "typed" file (top 12 bits of its load address all set) shows its filetype code and name in the LOAD column, and a decoded date — fixed to Europe/London regardless of your own timezone — in the EXEC column. An untyped/legacy file just shows its plain load and exec addresses.

READABLE / WRITABLE / LOCKED
ADFS has separate read and write access bits alongside the locked flag; DFS and MMB only have locked. The EDIT and ATTR (batch) dialogs show whichever set applies to the loaded format.

COMPACT
On old-map ADFS (S/M/L/D) it repacks the files of the directory you're browsing into the lowest free space. On E/E+/F/F+ it defragments the whole disc, like RISC OS *COMPACT, placing the current directory's files first in the order shown.

WHAT MMB IS
A beeb.MMB file is a container of up to 511 independent 200KB DFS disk images ("slots"), used by MMFS on SD/MMC card interfaces to swap disks without physical media. Loading one shows a scrollable slot list instead of a single catalogue.

BROWSING SLOTS
Click any slot to open that disk. Slots marked empty are unformatted and become formatted when you first save a file to them; slots marked locked are read-only in MMFS and here. Slots marked killed were removed with *DKILL but still hold their files: they open read-only, and RESTORE (like *DRESTORE) brings them back. Double-click a slot's name to rename it (the MMB index name; if the disc's own title differs, it's in the tooltip). The box above the list filters by number or name.

MMB TOOLS
+ ADD DISCS puts SSD/DSD images (or a ZIP of them) into free slots — or just drop disc images onto the MMB. EXPORT ALL downloads every disc as a ZIP of SSDs. FIND FILES searches file names on every disc. DUPLICATES lists discs with identical contents.

EXPORTING A SLOT
Each in-use slot has its own download button to export just that slot as a standalone .ssd file, without affecting the rest of the MMB.

PERFORMANCE NOTE
An MMB file is often ~100MB. The server only ever reads the discs it needs, so even hosts with small memory limits cope, and uploads go in pieces sized to what the host accepts.

UEF (TAPE)
UEF is a cassette-tape image format, holding files as Acorn cassette-format blocks. Full read/write: add, delete, rename and edit files, and create a blank tape from New Disk. Status messages say "Tape" instead of "Disk" when a UEF is loaded, and DEL/EXEC columns behave the same as DFS.

RFS (ROM FILING SYSTEM)
RFS is a 16KB sideways-ROM filesystem — multiple files packed into one ROM image, the kind used by things like the BBC Master Demonstration Cartridge. Full read/write is supported: browse, add, delete, rename and edit files exactly as with any other format.

ROM SETS (UP TO 64K)
A filing system bigger than 16K lives in several ROMs fitted in adjacent banks, read from the highest bank down — a file can carry on from one ROM into the next. Open or drop all the ROMs of a set together (2–4 .rom files) to load them as one catalogue; if they arrive in the wrong order, the working order is found for you. When a ROM fills up it grows into another 16K ROM automatically, up to four. SAVE then downloads a ZIP of the ROMs, numbered from 1: put ROM 1 in the highest bank, ROM 2 in the next one down, and so on. A single ROM from a set, loaded on its own, opens read-only.

A GENUINELY WORKING BLANK ROM
Creating a new RFS ROM builds a real, assembled 6502 boot handler — not a placeholder — so the result actually works if written to a real EPROM or used in an emulator, not just within this app. Editing an existing ROM never touches its original header or handler bytes, only the file catalogue, so it stays safe to edit regardless of which tool originally built it.

THE TITLE ENTRY
RFS conventionally starts with a zero-length "title block" naming the filing system. It's hidden from the file list (it isn't a real file), but it's still there and still renamed via the disk title field like any other format.

SINGLE-GAME ROMS AREN'T RFS
Some .ROM files (game cartridges with their own custom auto-boot code, e.g. most single-game ROMs) use the same paged-ROM header but have no file catalogue at all — the whole ROM is one block of code. These won't show a file listing here; there's nothing to browse.

KEYBOARD SHORTCUTS
(Active over a drive panel; ignored while typing in a field or with a modal open)

F1	Open drive 0
F2	Open drive 1
Enter	Edit the selected file
Delete	Delete the current selection
↑ / ↓	Move the selection up/down in the active panel
Escape	Close the open modal

WHAT HAPPENS TO YOUR FILES
Every uploaded disk is saved to a temporary server-side file tied to your browser session — never permanently stored, never shared between users, and never sent anywhere except back to you when you click SAVE. Idle sessions are automatically cleaned up. Uploads and URL imports are capped at 128MB.

DISKS LOADED COUNTER
The counter in the status bar is a running, never-resetting count of disks loaded (uploaded or imported by URL) or newly created from blank, by everyone who's used this tool — not tied to your session.

TIMEZONE
Dates shown anywhere in the app (RISC OS file timestamps, session info) are fixed to Europe/London, correctly handling the GMT/BST switch, regardless of your own device's timezone.

FEEDBACK
Something not working as expected, or just want to say thanks? Please contact me via Stardot.org.uk Forums.