Tooling and Disk Workshop

Tooling and Disk Workshop

Disk Workshop is the browser-local tool at tools/disk-workshop/index.html. Open that file directly after cloning the project; keep disk.js beside it. It requires no web server and uploads nothing. The selected disk is copied into browser memory; edits do not replace the host file automatically.

Import and install files

1. Run normal JavaVCPU at least once to install the system and initialize the directory, then stop the VM.
2. Back up storage.img and open Workshop's index.html in a modern browser.
3. Choose Open storage.img and select the project's 16 MiB disk.
4. Choose Import files, or New text file. For editor changes, choose Apply to disk.
5. Choose Download updated disk. The browser downloads storage-updated.img.
6. While the VM is stopped, replace the project's storage.img with the downloaded image using that exact name.
7. Restart JavaVCPU. Use DIR, then RUN, VIEW, IMAGE or PLAY for the imported file.

The directory allows 16 files of at most 240 bytes each. The tool preserves bytes outside its directory and initialization marker, including the BIOS/kernel. An import batch uses a working clone so a failed import does not partially apply the batch.

Editor and conversions

Select a directory row to inspect a file. Text / JVS uses ASCII text. Binary / COM, images and tunes use two-digit hex bytes separated by whitespace in the content editor. Choose the correct format when creating a new file. Renaming in the editor requires Apply to disk. Download file exports only the selected file. Delete file edits the browser copy; a disk download is still required.

Imported names are normalized to an eight-character base plus a three-character extension, uppercase; unsupported base characters become underscores. The underlying format supports up to 12 name bytes. Duplicate normalized names can replace an existing file, so check the directory after imports.

Import	Conversion / use
TXT, JVS, BAT, ASM, MD	UTF-8 decoded, then restricted to ASCII; CRLF becomes LF, tabs become four spaces
COM / other binary	Raw bytes; COM must use VM opcodes
PNG, JPEG, GIF, WebP, BMP	Proportional resize to at most 15 by 15, alpha composited on black, palette quantization
MID, MIDI	Standard MIDI format 0/1 with PPQN timing converted to JM events
IMG beginning JI	Existing guest image format
JMT	Existing guest music format

MIDI supports running status, tempo changes, note-on/off and four-note polyphony. Program changes and controller effects are not preserved; percussion becomes noise. More than four simultaneous notes or more than 59 output events requires shortening the input. The tune composer takes MIDI_NOTE FRAME_DURATION per line, up to 29 notes; e.g. 60 6, 64 6, 67 12 produces THEME.JMT.

Add sample files adds WELCOME.TXT, SMILE.IMG and THEME.JMT. Use VIEW WELCOME.TXT, IMAGE SMILE.IMG and PLAY THEME.JMT after downloading/installing the disk.

Palette preview	Short-tune composer

See Screenshots for the corresponding guest document, image and playback views.

Troubleshooting

Symptom	Check
No supported BIOS header	Start the current VM normally first; a blank or older-format image is rejected
File too large	240 bytes includes media headers and every source newline
Imported file absent in DOS	Apply edits, download disk, stop VM, replace correct working-directory disk, restart
Wrong execution behavior	Inspect file type; text is interpreted, binary is bytecode
Can't type	Focus the display window; hold quotes/backtick long enough for polling
Source error	Uppercase keywords, spaces between arguments, correct physical jump lines
Invalid executable	Import generated COM bytes, not text/hex or host executable bytes

The converter checks can be run by opening tools/disk-workshop/test.html. It exercises the format code in a browser. See Disk and media formats for byte layouts.