Ancient Web: Piotr Piatek Kept Programmable Casios Open to Inspection

Part of the Ancient Web Collection.

An old programmable calculator is not much use if its cassette interface fails and nobody remembers the undocumented commands. Piotr Piatek's website approaches that problem like an electronics workshop whose shelves happen to be made of hyperlinks.

Visit the Vintage Programmable Calculators archive.

Its main index ranges through Casio FX-700P, PB-700, PB-1000, PB-2000C, FX-870P, FX-8000G and other handheld computers, along with pocket-sized printers and floppy disk drives. For each machine, the links may include schematics, memory maps, manuals, emulator downloads, assembly-language notes and partially annotated ROM listings.

A model's official manual is only the beginning. On the PB-1000 section Piatek links a reconstruction of the internal six-kilobyte ROM, documentation for the HD61700 processor, a Forth implementation, and even a version of Tetris contributed by another programmer.

Recreating parts that collectors can no longer buy

The MD-100 replacement project goes beyond historical description. It documents a device using EEPROM chips to emulate the floppy storage portion of a Casio drive. A circuit diagram, prototype photograph, finished-board photograph and source-code archive are supplied. Piatek is careful to say that the parallel and serial ports of the original are not implemented.

The site also records imperfections. An alternative printer interface may miss characters when used with a fast computer, and a reconstructed VX-3 ROM listing was assembled from related machines instead of being read directly. Such admissions help future restorers understand what is known and what remains experimental.

The updates log documents ongoing emulator revisions into 2026, including ports to Lazarus and work on cassette and disk support. That makes the site a living specialist archive rather than a frozen homepage. Its historical value lies in preserving older hardware knowledge with the original diagrams, chips and file formats clearly identified.

There is no verified foundation date in the inspected pages, so a 1990s launch is not assumed. The hand-organized documentation and repair knowledge are enough to make the site distinctive.

The real achievement is that these machines are treated as understandable computers rather than sealed collector's items.

Explore the calculator index and MD-100 storage project.

Part of the Ancient Web Collection.