NEW MSX by TECNOBYTES

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Van Grauw

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04-05-2014, 04:09

No, gfx9000 is a v9990 chip, not compatible with v9938 (MSX2) / v9958 (MSX2+), and there are only a few small games for it.

That’s why this project has both a v9958 and v9990.

Van foody

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04-05-2014, 04:09

OK...had this card being a v9938 would that then turn my MSX1 and into an MSX2?

Van Grauw

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04-05-2014, 04:14

Something like it exists (NEOS MA-20) but it’s not common and many games still don’t work if you use it, because of some hardware addressing details. It’s better to just get an MSX2.

Van foody

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04-05-2014, 04:14

But you said that is why this project have both V9958 and V9990...but this for the new MSX, which is MSX 3..correct? So is it hard to have a card like this one GFX9000 that have the same chip as MSX 2 and thus you can upgrade your MSX 1 to MSX 2 using this card?

I am just curious.

Van Grauw

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04-05-2014, 04:26

Well if you want to know the technical details… The TMS9918 (MSX1), v9938 (MSX2) and v9958 (MSX2+) VDPs are all backwards compatible with each other and are accessed on I/O ports 98H-9BH. However, only one of these can be present on these I/O ports, otherwise if you read data, they would both try to answer and it will fail.

The NEOS MA-20 cartridge works by adding a v9938 VDP on another port range (88H-8BH), and replacing the BIOS with an MSX2 version. This BIOS contains information about the new I/O ports for the VDP. However many, many MSX2 software does not look at the BIOS to know what I/O port to use and just always uses ports 98H-9BH. Also there is an issue with the BIOS replacement which can cause some issues. This is why it works in theory but in practice there are a lot of compatibility problems and it is better to just get a real MSX2.

The Graphics9000’s v9990 is a completely separate, incompatible VDP, and therefore uses different I/O ports (60H-6FH). Because it is an additional VDP and does not need to be compatible with existing software, the above issues are not present. It has other issues though, e.g. it has a separate video output so you need two monitors or a manual switch. This TECNOBYTES MSX project solves that problem by using the superimpose-functionality, so that they can both use a single video output.

Van foody

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04-05-2014, 04:41

  • So what you are saying then is that technically speaking (both technically and theory wise) the GFX9000 and the opl4 are graphics card and sound card for the MSX, correct? Since the games at the time where developed with these two cards NOT on mind and never thought these cards would exist, the video card and sound card will not work with the games made already for the MSX2/2+, etc. That in order to enjoy these two cards you actually have to develop games or apps with these two cards in mind. Am I correct so far?
  • Am I also correct to assume that the NEOS MA-20 was suppose to be a patch to get the old "airplane" upgrades to new "airplane" features? Meaning this card was in theory a patch to make the MSX1 into MSX2, so people who own MSX1 and do not feel like to own two computers..would upgrade their MSX1 to MSX2 giving their MSX1 more usage time and now have more and better purpose than say throwing it away for MSX2. However, the games developed for the MSX is so badly coded and such a hack and forced code that it will not work on the NEOS MA-20 cartridge patch. But theory wise, this card should do the job and should technically upgrade your MSX1 to MSX2 100% like an MSX 2 but because the game is coded badly it will not work and thus you are forced to own MSX 2 regardless making this card useless and not necessary. Am I correct so far?

If what you are saying for the above statement is correct for both lists, then my real question comes why even make these cards from the first place if they are useless? Forget the NEOS MA-20, assume that these two cards gfx9000 and opl4 are indeed a video card and sound card and as specs they can do as good stuff as MSX3 could. Why not develop games for these two cards in mind...instead of making say MSX 3? Even if MSX 3 is going to be better than these cards, since these cards already exist and they do upgrade your MSX computer why not have great deal of game collections for these cards and when MSX 3 comes have games for MSX 3....thus making your game collections for these different configurations:

MSX/MSX2/MSX2+/Turbo-R/MSX3 and gfx9000 and opl4 MSX system combinations?

Van Manuel

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04-05-2014, 11:17

You 2 points are correct, in principle.
But:
- The NEOS MA-20 is a very rare piece of hardware. Only a few are known to exist still today. It's only released in Japan around 1986 by the professional company Neos (Nihon Electronics). At that time it wasn't of course useless at all.
- There is also a lot of software that did keep to the standard which works fine with it
- GFX9000 is a hobby project which got released around 1995. It's an add-on. It's not meant to be compatible. It needs software written for it specifically. So, it becomes useful if people write software for it. (Chicken/egg thing.) It was not useless at all when released, it just needed people to write software for it (like for all new hardware).

It's not useful to write something specifically for the Neos MA-20. You can then just as write something specifically for MSX2 (and keep to the standards). WHich has already been done a lot, as I already pointed out. But just forget about the Neos MA-20. It's a curiosity.

And yes, I hope people develop for the GFX9000. I think/hope that the Tecnobytes MSX3 will be compatible with the GFX9000 cartridge.

Because the cart isn't compatible with the MSX1/2/2+/tR video chips (as grauw pointed out), you always get a game either for one of these (where they are all backwards compatible) or for the GFX9000. OPL4: you either write music for OPL4 or for the other chips (or both, as has been done often). And then there are some other requirements for games, like RAM, or DOS2. That doesn't directly depend on MSX type, but it does depend on what you have in your machine.

Van Grauw

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04-05-2014, 13:09

@foody Your two points are correct although I wouldn’t go so far as calling that software “badly coded”. Information was simply limited at the time, especially in Europe, and as all known MSX computers had their VDP in the same port, it’s no surprise this happened.

Also, even if they knew, people probably simply did not care to support this MA-20 curiosity. For sure this is the case for me now. And it is said the MSX2+ standard specifies that the VDP will always be on ports 98H-9BH, so that settles the debate.

As for Graphics 9000, indeed people can develop software for it today on MSX1 / MSX2, you can plug in an OPL4, IDE and 4 MB RAM too (I have all these). However it’s nice to have a new system which includes these, because cartridge slots are limited and by bundling it like this it kinda sets a new base standard. Also combining graphics on one video output is a great feature. A HDMI or VGA output would be nice to have, I hope it will be included in the specs.

p.s. @Tecnobytes: I think it would be better to have an SD-cardreader rather than an IDE interface…

Van foody

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04-05-2014, 13:55

Think you Gauw and Manuel for clarifying it to me Smile. It is nice to know with msx you can develop your games based on your favourite chip...hehehe..like a console! Grauw I was hoping they implement both IDE and CF combination for people like me who still like the good old days IDE HD with mechanics and slow RPM choice......Smile

Actually if msx 3 did come up and manage to get new games developed for it that makes gfx9000 super useful as games will be developed for it and thus I can hook it into my msx 1 to make it run these games...I might consider going through this route for msx 3 games instead of getting the actual msx 3. Bare with me I am just thinking loudly.

Van Manuel

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04-05-2014, 14:33

As everyone said: just get an MSX2 or higher with more built in RAM and you'll be so much more enjoying MSX stuff.

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