Ghosts from the past... If you've been reading this blog a long time, then you probably already know that I'm the author of Tarbell Basic. What? You never heard of Tarbell Basic? Well, don't feel bad – neither has about 99.99999% of humanity, and about 99% of the remainder wish they hadn't heard of it :)
I wrote Tarbell Basic in the late '70s, nearly 40 years ago. In the world of software, that qualifies as genuinely ancient history, I think. It was written in Z80 assembly language to run on the operating system CP/M, using an assembler, linker, and debugger that I also wrote as part of the same project. The last time I worked on any of the source code for Tarbell Basic was probably in 1980 or 1981 – about 35 years ago.
I have no memory of when I last had an actual copy of that source code, but I strongly suspect that it was around the same time I switched over from CP/M to MS-DOS for my development environment – in 1982 or 1983. It wasn't so easy to move files from CP/M to MS-DOS, and so far as I know I never did move the Tarbell Basic source over. In any case, I haven't had access to that source code for something like 35 years.
Starting about 15 years ago, or maybe a tad more, I've occasionally been contacted by an enthusiastic hobbyist. It's happened several times a year; probably over 50 times altogether by now. Most often they want help fixing a bug they've found in Tarbell Basic. Sometimes they want help understanding the non-standard Z80 mnemonics we used. Sometimes they want the latest version of the source. Once (just once!) someone wanted me to autograph their copy of the Tarbell Basic manual (I did!).
This morning I had two people contact me about Tarbell Basic. One fellow, from New York, was very insistent that I immediately email him a copy of the very latest source code. When I emailed him back to tell him that I couldn't do that, as (a) I no longer had access to it, and (b) I didn't own it – he threatened to sue me, and recommended that I “lawyer up”. I wonder what theory he'd pursue in a lawsuit? Willfully thwarting a New Yorker? I wrote back telling him to quit being such an idiot, and asking why this was so important to him. I got an answer just now: this guy is running his business (a pawn shop) on a custom program written in Tarbell Basic! It was originally written in the early '80s for a CP/M machine, and was long since ported to a standard PC running a CP/M emulator. His current programmer, a kid, told him that he had to have the source code to modify Tarbell Basic to accept bigger programs, as he was out of memory. Hah! I told him he was doing the equivalent of patching his horse-drawn chariot to compete with modern taxis, and he should bite the bullet and rewrite it in a language from the current century. We'll see what happens with that :)