VIA 6522 support in Emulator

StephenHorn · Post by **StephenHorn** » Fri Apr 02, 2021 10:33 pm

1 minute ago, Elektron72 said:

Are you referring to the BSD license or to the GPL and the FSF?

Ack, seems we both flubbed that. Of course I meant GPL.

Wavicle · Post by **Wavicle** » Sat Apr 03, 2021 2:55 am

7 hours ago, Elektron72 said:

If you find a VIA emulation library licensed under the MIT, BSD, Apache, or similar licenses, then using it in the project should be fine. On the other hand, we cannot use GPL-licensed code in the emulator (due to this, we'll probably have to replace the ambiguously-licensed YM2151 emulation at some point; luckily, someone has already found a suitable replacement).

Jarek Burczynski has set the license for his YM2151 driver source as GPLv2. See this commit in the MAME source.

ETA: The latest YM2151 driver in MAME is BSD 3 Clause: mame/ym2151.cpp at master · mamedev/mame · GitHub - that one might be better for the X16 emulator.

BruceMcF · Post by **BruceMcF** » Sat Apr 03, 2021 4:11 am

6 hours ago, ZeroByte said:

I think I'm just going to release most of my stuff into public domain - lol.

Note that in some countries there is not really such a thing as a release into the public domain of code still in its copyright period ... AFAIU there are some European countries where were a creator could say, "never mind" and the code would be under copyright again ... and that is what is handy about the Creative Commons CC0 license ... it gives a close equivalent to a release into the public domain even in countries where releasing something into the public domain isn't supported.

https://creativecommons.org/share-your-work/public-domain/cc0/

StephenHorn · Post by **StephenHorn** » Sat Apr 03, 2021 5:05 am

51 minutes ago, BruceMcF said:

Note that in some countries there is not really such a thing as a release into the public domain of code still in its copyright period ... AFAIU there are some European countries where were a creator could say, "never mind" and the code would be under copyright again ... and that is what is handy about the Creative Commons CC0 license ... it gives a close equivalent to a release into the public domain even in countries where releasing something into the public domain isn't supported.

https://creativecommons.org/share-your-work/public-domain/cc0/

That's another good point in favor of including at least some sort of license.

TomXP411 · Post by **TomXP411** » Sat Apr 03, 2021 6:03 am

8 hours ago, ZeroByte said:

So what is it about GPL that is so incompatible? I mean, I haven't gotten out my legalese decoder kit and started reading to know what it is. Every time I read GPL, it seems like it basically says "anyone can do anything except not include the source and the list of changes" - is it this last proviso? I have been finding several emu projects that have good VIA support, but they all seem to be using GPL because, at least from my own perspective, that's "just the one everybody uses" - I think I'd rather go hungry than be a lawyer, so if there's a TL;DR version of why GPL is incompatible with BSD licensing, I'm very curious.

I mean, I've even used plenty of proprietary closed-source commercial applications and devices which made use of GPL software, and there's usually a README or "ABOUT" page that mentions the presence of opensource code being available upon request / available in the "extra crap" folder, etc... Couldn't x16emu do the same thing - i.e. include a GPL license for the YM code and make that an explicitly-mentioned thing in the sources / license documents? Again, I'm not legal-savvy so this is an "educate me plz" post, not a "let's do this and everything will be fine" post.

I suspect it's the part that says nothing more restrictive can ever happen to this code... (section 6)

GPL requires you to GPL (or compatible) anything you create with GPL code.

This is the primary distinction between GPL and things like the BSD or Apache license, which allow you to use those products to build software that is not necessarily open source.

The requirement to GPL anything that includes or statically links to GPL code is why the GPL is often called a "viral" license... and so you can't mix GPL with more permissive licenses like the BSD license.

On one hand, it forces companies like Red Hat to continue giving away their Linux distros for free... on the other hand, it makes it difficult to use open source bits of code in commercial programs. So if I make a BSD licensed audio program, and I want to use something like LAME to encode the audio to MP3, I can't without adding the GPL's restrictions to my product.