Elektor and OSI's OS-65D (was OHIO-DOS)

As the owner of a modified and still-working OSI Superboard 2 running under OS-65D 3.3, I may have a few insights about the Elektor link to OS-65D: - I had owned my machine for around 5 years (that would make it 1985) when a friend showed me the two-part Elektor article of a floppy-disk interface for the ongoing "Junior Computer" series. Using the schematics, I hand-wired (anyone else remember Vector's "Pencil Wiring" with solder-through insulation?) a disk interface for my Superboard. - The Elektor article "adopted" OS-65D because OSI sold the DOS as a stand-alone product, complete with utilities for customizing disks, developing code in BASIC and Assembler, and capable of running serial or memory-mapped user I/O with the change of a byte in DOS. It sounds like the Elektor authors went forward and used OD-65D for later projects. - By 1985, MA/COM had renamed OSI to ISOTRON during the slow- and shut-down of manufacturing - they stopped buying masked ROMs, and made Superboards and C1Ps patched to use 2716 EPROMs instead - but were still selling the Disk OS. When I telephone-ordered a copy and asked for "OS-65D V. 3.3 for a C1P", a fellow worker figured I was some sort of spy speaking code! Fortunately, the folks at the factory knew what I was talking about. The documentation binder bears the name ISOTRON on its cover. - Like the Elektor authors, I patched my OS-65D, for an 80x24 video card in my system. I had written extensions into a copy of the OSI Monitor ROM: I was a little peeved when OS-65D loaded, ignored the redirected video, and brought in its own drivers for the original 24x24 screen... I was sooo glad I maintained back-compatibility. I still have the original OSI disks and docs: there are 5 disks with all sorts of utilities (mostly in BASIC), the binder for the OS and separate manuals for the "Assembler/Editor and Extended Monitor" and disk BASIC. The handiest thing (and most well-worn!) is the little fold-out card listing DOS commands, memory locations and error code descriptions. I'm a little puzzled at the reference to OS-65D V3.2... Version 3.3 was the "full" version, and the single-floppy reduced version was 3.1: perhaps someone patched a version 3.1 disk for their own project, and just incremented the number? Bob Maxwell --- Original Message ---