DSK Manager

A command-line tool and Rust library for reading, writing, and analyzing DSK, MGT, and TRD disk image files. Built for retro computing enthusiasts working with Amstrad CPC, ZX Spectrum +3, Amstrad PCW, SAM Coupe, and IBM PC floppy images.

Install

cargo install --path .

Or run directly:

cargo run --bin dsk

You can also open a file directly from the command line:

dsk disk.dsk
dsk disk.mgt
dsk disk.trd
dsk disk.json

CLI

dsk is an interactive REPL for exploring disk images. Open a file and poke around:

> open game.dsk
> info
> tracks
> sectors
> fs-list
> map
> verify

Commands

Disk management

Command	Description
open <path>	Open a .dsk, .mgt, .trd, or .json file
save <path>	Save image (format determined by extension)
create [amstrad|spectrum|pcw]	Create a new blank disk image
info	Show disk information
spec	Show the disk specification (geometry, filesystem layout)

Filesystem

Command	Description
fs-list	List files on the disk (cat, dir, ls also work)
fs-read <filename>	Display file contents
fs-export <filename> [output] [raw]	Export file to host (strips headers unless raw)
fs-switch [auto|cpm|mgt|trdos]	Switch filesystem driver
fs-info	Show filesystem details

Low-level

Command	Description
tracks	List all tracks
sectors	List all sectors
read-sector <side> <track> <sector>	Dump a sector (sector ID can be hex like 0xC1)

Analysis

Command	Description
detect-protection	Detect copy protection schemes
disassemble [track] [sector]	Disassemble Z80 code from a sector
strings [len] [uniq] [charset]	Search for strings in the disk image
map [side]	Visual sector map (▓ = in use, ░ = empty)
verify	Verify disk structure and filesystem integrity

File Formats

Disk image formats

Format	Extension	Description
Standard DSK	.dsk	Fixed track size (Amstrad CPC, Spectrum +3, PCW)
Extended DSK	.dsk	Variable track sizes, SAMDisk V5 extensions
MGT raw	.mgt	800KB DSDD raw sector dump (SAM Coupe, DISCiPLE/+D)
TRD raw	.trd	TR-DOS raw sector dump (ZX Spectrum Beta Disk Interface) — experimental
JSON	.json	Human-readable, editable representation of any format

open and save detect the format from the file extension. You can open a .dsk, edit it, and save as .json — or vice versa. JSON files preserve all metadata (CHRN IDs, FDC status, per-sector data lengths) so the round-trip is lossless.

Disk geometry presets

Built-in configurations for common formats:

• Amstrad CPC System/Data (40 tracks, 9 sectors, 512 bytes)
• ZX Spectrum +3 (40 tracks, 9 sectors, 512 bytes)
• Amstrad PCW (40 tracks, 9 sectors, 512 bytes)
• IBM PC 360K/720K (40/80 tracks, 9 sectors, 512 bytes)
• Tatung Einstein
• MGT Disciple/+D/SAM Coupe
• TR-DOS (80 tracks, 16 sectors, 256 bytes, single-sided)

Filesystems

• CP/M — read-only support for Amstrad CPC, Spectrum +3, PCW, and Tatung Einstein
• MGT — read-only support for DISCiPLE/+D and SAM Coupe (SAMDOS, MasterDOS, BDOS)
• TR-DOS — experimental read-only support for the ZX Spectrum Beta Disk Interface (directory listing and file extraction; writing not yet implemented)

Copy protection detection

Automatically detects 20+ copy protection schemes used on Amstrad CPC and ZX Spectrum +3 disks: Alkatraz, Speedlock, Hexagon, Frontier, Paul Owens, Three Inch Loader, P.M.S., DiscSYS, Mean Protection System, KBI-19, CAAV, KBI-10, and many more.

Library

DSK Manager is also a Rust library. Add it to your project:

[dependencies]
dskmanager = "0.1"

use dskmanager::{DiskImage, FormatSpec, CpmFileSystem, FileSystem};

let image = DiskImage::open("disk.dsk")?;

let data = image.read_sector(0, 0, 0xC1)?;
println!("Sector data: {} bytes", data.len());

let fs = CpmFileSystem::from_image(&image)?;
for entry in fs.read_dir()? {
    println!("{}: {} bytes", entry.name, entry.size);
}

let mut image = DiskImage::create(FormatSpec::amstrad_data())?;
image.write_sector(0, 0, 0xC1, &vec![0xE5; 512])?;
image.save("new_disk.dsk")?;

License

MIT OR Apache-2.0 at your convenience.

Contributing

Contributions welcome! Please ensure:

1. Code compiles without warnings: cargo build
2. Tests pass: cargo test
3. Code is formatted: cargo fmt
4. No clippy warnings: cargo clippy

Run the test suite:

# Unit tests
cargo test --lib

# Integration tests
cargo test --test integration

# All tests
cargo test

Acknowledgments

• Claude Code, Copilot, and Cursor are used in the development of this library and tool
• Based on my original Pascal/Lazarus DiskImageManager implementation