GW-BASIC VS 8088_bios

Fun fact...Microsoft open sourced GW-BASIC under the MIT license a couple years ago...

https://github.com/microsoft/GW-BASIC

The blog post announcing it is here if you want more information about it...

https://devblogs.microsoft.com/commandline/microsoft-open-so...

I'm way ahead of you :)

Unfortunately, rewriting it without reverse engineering makes it almost impossible to reach the same performance characteristics. These are essential to reproduce proper timing in several games.

Also, it may not be much code, but the floating point operations are quite a piece of art. See the GW-BASIC source code, which is somewhat similar [1].

I also rewrote most of the BASIC interpreter directly in Kotlin, omitting assembly, but obviously that runs into the same compatibility issues.

As far as I understand it, reverse engineering is not allowed without permission, although some people suggest that it is ok to get other software to run. Not sure whether that case would hold up for my entertainment value.

[1] https://github.com/microsoft/GW-BASIC/blob/master/MATH2.ASM

Someone could take this and try to make it ROM-able in order to "complete" the BIOS:

https://github.com/microsoft/GW-BASIC

Hey! They use an emulation. You can implement this yourself but it's quite the undertaking if you also want trigonometry functions etc. There are libraries available but they can be hard to build on older compilers, search for floating point emulation c library to get some ideas. Depending on what you want to do however are you sure you need floating point? I thought so in the past but have reconsidered. Many times you can work something out by either scaling or smart fractions like 355/113 for pi etc. Regarding scaling, this is also how fixed point math works, certainly also of interest and maybe more then enough?

> but if ever the source for QBasic leaked

QBasic? - Why that modern thing. Just use the proper BASIC: https://github.com/microsoft/GW-BASIC ;)

Microsoft GW-Basic Interpreter Source Code\ (20 comments)

Just a heads up, it looks like these guys ripped off Serge Kiselev's 8088 BIOS [1].

[1] https://github.com/skiselev/8088_bios

There are at least three "real" 8086 BIOSes-- "real" as in they can work on actual hardware rather than just emulators-- available in source form, which might be worth examining.

https://www.phatcode.net/downloads.php?id=101 -- this is a respin of code that apparently originated in the 1980s in sketchy Taiwanese clones, so I think some of the docs are reverse engineered

http://glabios.org/ is an all-new-still-under-development project, but it works well enough for my hobby usage.

https://github.com/skiselev/8088_bios These are more targeted towards some specific hardware projects (Xi8088/Micro8088)

Obviously, being for a simple 8086 mrans they don't have some of the complex chipset config used in a modern PC, and even stuff like "hard disc support" is outsourced (for that, you might consider stuff like the XT-IDE Universal BIOS)

And another: https://github.com/skiselev/8088_bios