C-128 WorkSpace is a graphical desktop for the Commodore 128, written entirely in BASIC v7.0. A menu bar, twelve tools behind twelve PETSCII icons, windows with shadows, dialogs, three themes and a textured ground — on a 1 MHz VIC-IIe, in forty columns, with no REU, no 80-column monitor and not one bitmap. It draws by POKEing screen codes straight into screen and colour RAM, and it boots in about three seconds.
The C128 shipped with more machine than anyone gave it software for: an 8502, 128 KB, two video chips and a BASIC good enough to write real programs in. What it never got was a desktop that felt like one. GEOS was the C64's, and it wanted a mouse and time. WorkSpace is the other answer — keyboard and joystick, forty columns, instant.
The rule the whole thing is built around: the 40-column desktop is the mandatory primary UI, and it must run on a stock machine. No REU, no 80-column display, no bitmap assets, no cartridge, no modern libraries, no assumed mouse. If a C128 straight out of its box in 1985 cannot run it, it does not ship.
There is a second edition for people who do have the 80-column monitor — WorkSpace OS 128 v2.1, on the VDC at 2 MHz, with a two-pane launcher and seventeen applications. It shares the tools' logic with the 40-column desktop and changes only the presentation layer, which is the point of splitting them: the renderer, the theme manager, the dialog manager and the disk service are replaceable layers, so the interface can be rewritten without touching a single tool.
A desktop for a machine that never got one — forty columns, one megahertz, and it opens in three seconds.
files (a disk browser that runs, views, copies, renames and deletes) · calc · system (CPU, MMU and VDC report with a colour bank map) · memory (hex viewer) · clock · music (SID) · speed (1 vs 2 MHz benchmark) · sprite (a 24×21 editor that writes with SPRSAV) · disk (DOS status, validate, rename, format) · setup · help · editor (a line-based SEQ text editor that loads and saves to disk).
F1 to F5 open Disk, Tools, Media, View and Help; cursor keys or the joystick move, RETURN picks, ←/→ switch menus, ESC closes. The menus are a data-driven registry, so a new item is one line of DATA.
The launcher highlight moves with the cursor keys or a joystick in port 2, and only the two tiles that changed repaint — the one you left and the one you landed on.
Classic Blue, Dark Terminal and Light GEOS, each one a line in the theme manager. The desktop texture is checker, dots, mesh or plain, and the icons are plates or flat. All of it switches live in Setup.
Windows are drawn as shadow, frame and title by one primitive, and every dialog — alert, confirm, input, error — comes out of the same four routines. Leaving a tool restores the desktop underneath instead of redrawing it.
WorkSpace OS 128 v2.1 on the VDC at 2 MHz: a scrollable applications list of colour icon chips beside a live information panel, a clock that keeps ticking while you browse, and seventeen apps including a PETSCII character map and a dec/hex/binary converter.
Drive number, the video mode it detected by peeking 215, and a running clock.
c128-apps.d64 opens on a boot menu as its first file, so a cartridge's mount-and-run lands straight on it: press 1 for the desktop, 2 for the 80-column workspace.
The renderer writes screen codes and colour straight to 1024 and 55296. Five primitives — string, character, box, fill, window — are the whole drawing surface, and every tool is built on them, so a change to the look is a change in one place.
Hand-assembled fill, save and restore routines live in the documented C128 free-RAM block. Fill floods all 1000 screen cells and 1000 colour cells in one SYS; save copies the finished desktop to a buffer; restore blits it back. They touch only screen RAM, colour RAM and their own buffers below the BASIC program.
C128 BASIC keeps scalars first and arrays after, so creating a new scalar once the arrays exist shoves the whole array block up to make room — and the desktop dimensions about 7 KB of arrays. The palette routine alone measured four seconds of that. Predeclaring every variable before DIM took the cold start from ~31 s to ~22 s.
The remaining time was painting twelve framed tiles cell by cell, and that screen never changes — so it is captured once and blitted. Three companion files carry the ML helpers, the screen-code image and the colour image; boot BLOADs them and runs restore. Cold start fell to about three seconds.
Each captured image carries a version byte and a checksum. Boot checks the loads landed and that the version matches the one baked into the program; if a file is missing, a load fails or the version disagrees, it falls through to the original BASIC draw. A disk without the images still boots — just at the old speed.
The same idea inside the tools, in pure BASIC: the file browser and the text editor used to rebuild all sixteen visible rows on every cursor press. They repaint the two rows that actually changed, and re-read the disk only when something on it changed.
The source is tokenized with VICE's petcat at BASIC v7.0 and round-trips byte for byte, which is what proves every token is legal and nothing was invented.
No dangling jumps, no two-character variable collisions, no writes to reserved variables — the kind of thing that only shows up three menus deep, months later.
The three 6502 helpers are assembled again by an independent assembler in the build checks and compared against the bytes in the DATA statements, so a typo in a hex digit cannot ship.
Both programs are run in VICE with genuine C128 ROMs and confirmed to reach their desktops: the 40-column launcher and the 80-column WorkSpace splash.
A C128 as it came in the box. No REU, no 80-column display for the primary UI, no cartridge, no mouse.
Legal tokens only, proven by tokenizing with petcat. The 6502 helpers are bytes in DATA, so no assembler is needed to build it.
Every accelerator checks itself and drops to the slow path rather than paint the wrong screen. Nothing can end up half-drawn.
Tombatossals Softworks LLC.
Not yet. The repository is private, so there is no public disk image and no public source today. When that changes this page will carry the link — until then, everything described here is described, not offered.
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