Not too long ago I had a need and an opportunity to re-acquaint myself with the mechanism used for software emulation of the 8087 FPU on 8086/8088 machines.
↫ Michal Necasek
Look, when a Michal Necasek article starts out like this, you know you’re in for a learnin’ ol’ time.
The 8087 was a floating-point coprocessor for the 8086 and 8088 processors, since back in those early days, processors did not include an integrated floating-point unit. It wouldn’t be until the release of the 486DX, in 1989, that Intel would integrate an FPU inside the processor itself, negating the need for a separate chip and socket. Interestingly enough, Intel also released a cut-down version of the 486 with the FPU removed, the 486SX, for which an optional external FPU did exist.
…though, as Wikipedia says:
Thank you Clippy!
Yeah, but the cool kids have Weitek and, yes!, our software did support it! Not many did though.
I remember the time when, in my 286, i received a pirated copy of Autocad 10 and I wanted to run on it anyways, excecuted the 8087 emulator , opened the program and let it load the “demo”, a 3D diagram of the space Shuttle. I think it lasted two hours to draw that completely, but, oh man, that’s was pure joy and glory
I had a 286 with a Hercules graphics card and alien green CRT. Monochrome only, but it did have a graphics mode. Every draw seemed to take an eternity. The screensaver trails were amazing – I wish I still had it.