This story came together fully in the very late stages of production of my new book about Sphere, Go Computer Now!, and includes new reporting that didn’t make the book. So here, for the first time, I’d like to tell the rather incredible story of Sphere BASIC.
Titled “Provisional BASIC,” Sphere’s version of the user-friendly programming language arrived late—some six months after the Sphere itself… it was huge, requiring nearly twenty kilobytes of memory… once loaded, Sphere BASIC was slow. Incredibly so.
Sphere Provisional BASIC, of April 1976, was in fact an emulated version of Hewlett-Packard’s single-user BASIC, a system then in wide use on the line of HP 2100 series minicomputers.
And yet, you don’t find an HP2100 emulator in there - the story is more interesting than that!
About this kind of emulation being rare in 1976, there was the famous IBM 5100 from 1975 emulating a System/370 to run APL and a System/3 to run Basic. But its PALM processor had been designed for the task.
While the 6502 was pretty awkward at handling 16 bits (which is why Woz included his Sweet 16 emulator to make Integer Basic easier to implement) the 6800 was a bit better at it (and the later 6809 was great at it).
But note that nothing released by Apple ever actually used Sweet-16… Woz’s Game/Integer Basic didn’t actually use it.
And as a “seasoned” 6502 programmer, I don’t think it’s awkward at all - it’s just different, having 128 x 16-bit registers at your disposal - you just have to load and store the registers one byte at a time. (Obviously biased here due to 48 years of writing 6502 code!)
