I am curious if anyone can list some sources that really explain how to do standard 40-bit FP on a 6502. I’m aware of some sources from the 1970s, but have not come across anything really in-depth.
For instance, I’ve seen Woz’s code from Dr. Dobbs in 1976, but it is almost completely undocumented. A number of similar code-pulls from things like Commodore BASIC or Atari BASIC are easy to find, but they only explain the code, not the underlying theory.
There are some recent web pages that talk about different aspects, like Calc65, but this is really an application as opposed to an explanation and assumes you understand all the basics.
Finally, there are some in-depth sources, mostly books from the late 1970s. But I have been told they generally do not closely match real-world implementations, as there were issues with them that “everyone knew” but are never explained.
So does anyone know of a really good resource for this? One that starts with the basics but also has comparisons of various approaches and their trade-offs? One that explains, for instance, how the MS FP system works and then explains alternatives/problems/tradeoffs/improvements?