Question about Turbo R hardware

Prophet (2135)

22-08-2010, 14:20

For some reason, I have always been fascinated by the technology behind computers and especially MSX. Even back then when I still actively used my MSX 2+ ,while I wasn't a programmer or hardware builder, I had a pretty decent understanding how games were build, how the music/graphics were created by the computer, I knew the specifications of most parts etc.

This curiosity never left me, and after all these years I am still wondering why it wasnt possible to mod your msx 2 or 2+'s into a turbo r.

Back when the MSX 2+ came out, shortly after it, it was possible to upgrade your msx2 to a 2+ by changing the videoprocessor, and iirc some new rom or whatever.

Though my knowledge of computer hardware is only based on theory, I can imagine the same thing being done for a upgrade to MSX turbo R. Switching the Z80 for a R800, update the rom, and add a adpcm chip somewhere. Maybe expand the internal memory to 256/512 to make it fully compatible.

I was just wondering why this was never done? Is the architecture of the Turbo R so much different compared to the msx 2(+)?

This is not a complain/demand thread ("omg still cant upgrade to turbo r? you guys suck!"), I am really curious about this since it has puzzled me for the last decade I think.

By muffie

Paladin (933)

22-08-2010, 14:44

Among several other things, it have both processors: z80 and R800. Just because of that, LOTSA strange electronic things would need to be implemented...

By Jipe

Paragon (1625)

22-08-2010, 16:22

download the Turbo-R manual and see
is not just a MSX2 + upgraded
look at the S1990 chip !!

By karloch

Prophet (2159)

23-08-2010, 00:45

As people is telling to you, a Turbo-R is not just a "MSX 2+ upgrade". In order to add the R800 processor while keeping backward compatibility, complex architecture was needed. In order to reduce this complexity, integration of components under one single chip was performed in the S1990 (it looks like Nishi was already aiming at developing a one chip computer).

Even if to the average user there is no big difference with a MSX 2+ computer, the internals are completely different from previous generations of the standard.

EDIT: No wonder why no one has adventured into making an amateur TurboR. Padial's ESE-MSX or CIEL one are boosted MSX 2+ with high frequency Z80's. Official One Chip MSX can go to MSX 2+ as maximum specs (and thanks to KdR's development). The reason is simple: it's not worth to go into that design hell for the little achievement you are going to get; way better and easier to boost your MSX 2+.

But ey, that makes our Turbo-R machines quite unique

By RetroTechie

Paragon (1563)

23-08-2010, 02:19

And last but not least: no parts, no documentation. Can't buy that MSX2+ engine that's also in there, can't buy an S1990, can't buy a loose R800. So you'd have to re-implement all that stuff in a new custom IC (mega-$$ project, won't happen), or in a large FPGA which would be very hard without documentation on the internals of MSX2+ engine / R800 / S1990.

But ey, that makes our Turbo-R machines quite unique
Unique + undocumented = dead end. While the Turbo-R is a nice machine, that's always been the case & the Turbo-R is no exception.

By muffie

Paladin (933)

23-08-2010, 02:48

Well, I'm very happy to own one.
Even if it's stored in a closet!
BUT, I would fell better owning a GT...

By syn

Prophet (2135)

25-08-2010, 22:50

Yes I understand now, thank you. In one of the newsposts about the turbo r game X-tazy someone mentioned that he could run it on his msx 2 or 2+ but it was very slow. So I thats why I thought the r800 was just a z80 at higher speed. But I gues the programmers just didnt used any turbo r specific stuff that the r800 was capable of and just pretended it was a z80 on crack, am I right?

I always wanted to have a turbo r, but even now I dont want to spend 300+ euros for a system that only has a limited number of software. With that money i rather buy some new hardware expansions for my current msx 2+.

Or I buy some retro console stuff like a neo geo arcade board or a new cpu for my pc

By edoz

Prophet (2501)

27-08-2010, 22:21

X-tazy runs verry well on my msx2+ and 7mhz and moonsound... when there are no enemies the game runs smooth .. but if there are more than three enemies the games gets slower .... to verry 'to' slow.. on 3 mhz is to slow... but it works..

By edoz

Prophet (2501)

27-08-2010, 22:31

You can also use an emulator if you don't have a turbo-r. I have both ..Turbo-r GT and MSX8280 (2+ 7hmz) .. the most time i used my msx2+ and not my turbo-r ..
The 7 Mhz is enough for me and not to slow ... Just right.. and i don't like the keyboard layout on the turbo-r..