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Author Topic: One Chip MSX mkII - a chance for an Enterprise in FPGA? (Read 13989 times)

Offline marcof

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One Chip MSX mkII - a chance for an Enterprise in FPGA?
« on: 2006.August.21. 16:32:07 »
I'm a big MSX fan. But I own an Enterprise 128 for some years as well.
on MSX.org, there's new development for a "one-chip" MSX on FPGA. I think this could also be used for enterprise, since the CPU is the same (Z80), only the architecture would need to be developed in VHDL.

Any info on project like this?

Offline lgb

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One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #1 on: 2006.August.21. 17:25:09 »
Quote from: "marcof"
I'm a big MSX fan. But I own an Enterprise 128 for some years as well.
on MSX.org, there's new development for a "one-chip" MSX on FPGA. I think this could also be used for enterprise, since the CPU is the same (Z80), only the architecture would need to be developed in VHDL.

Any info on project like this?


Also, there is an open source Z80 core (called t80) at opencores.org as far as I can remember. You can buy some FPGA development  board and play with these stuffs. Also, you can buy a C-1 (Commodore One) ATX motherboard, which carries two FPGAs, and there is some CPC core currently for example ... Major advantage of a C-1 motherboard, that is has got connectivity for common hardwares, like PC case+power supply, PS/2 keyboard, VGA monitor ... So you can focus on the FPGA core itself without the need to create everything from zero.

Offline tigrian

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One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #2 on: 2006.August.21. 18:37:50 »
Yes it wold be possible to create such design. But the Enterprise 128 has two special chip, NICK and DAVE, and nobody knows their insides exactly.
However, it is not impossible to make it. But there is another thing. Most of us are agree that the Enterprise 128 means not only the software but the design and hardware as it is. Running EP softwares are easy: just pick up a simulator. There are at least two of them we are using every day. But the "Enterprise feeling" is more than that.   :smt001
We who implement hardwares to the EP, are trying to expand its possibilities, instead of substituting them.

Maybe others have different opinions.  :wink:
re' mi' do' do sol

Offline marcof

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One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #3 on: 2006.August.21. 19:15:43 »
Quote from: "tigrian"
Yes it wold be possible to create such design. But the Enterprise 128 has two special chip, NICK and DAVE, and nobody knows their insides exactly.
However, it is not impossible to make it. But there is another thing. Most of us are agree that the Enterprise 128 means not only the software but the design and hardware as it is. Running EP softwares are easy: just pick up a simulator. There are at least two of them we are using every day. But the "Enterprise feeling" is more than that.   :smt001
We who implement hardwares to the EP, are trying to expand its possibilities, instead of substituting them.

Maybe others have different opinions.  :wink:


Actually, if you consider FPGA, it is possible to addd new hardware (using VHDL) and extensions more easily. I agree that the "enterprise feeling" is special (same goes for MSX of course), but FPGA also offers possibilities to extend the system more than is possible now, for a smaller budget as well.

Regarding Nick and Dave, I think this might be an issue. Although there's also FPGA Arcade. I think that guy "reverse engineers" the systems by grabbing timings over PINs... difficult, but I guess the same can be done for Nick and Dave.

Anyway, it was just an idea that popped up. I wished my hungarian was, well.. at least something :) I'd like to look for much more EP hard/software, but apart from german, french, english (some korean and japanese), hungarian is not in my vocabulary :)

Would be nice to have the full specs of Nick and Dave indeed...

Offline pepax

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #4 on: 2008.July.23. 22:35:47 »
Would be nice to have the full specs of Nick and Dave indeed...

Has anyone ever asked Nick or Dave if it was possible to find the specs somewhere?

Offline Jimmy

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #5 on: 2008.July.29. 14:06:41 »
IMHO, there is enough specifications to prototype them both.
When I was a student (long time ago :lol:), I've designed Nick on a discrete chips. Dave was more complex for me as I haven't known how to synthesize noise by the mean of polynomial counter or make a distortion effects by the same means.

Offline Zozosoft

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #6 on: 2008.July.30. 12:46:41 »
IMHO, there is enough specifications to prototype them both.
But not enought for the 100% compatibility :-(
In the hungarian forum, now we discussing about timing problems in the emulators. The ep128emu developed by the documentations, but now I found many difference about the memory and video memory access timing in the real and emulated machine.
Quote
When I was a student (long time ago :lol:), I've designed Nick on a discrete chips.
Wow! It is exist any documentations about this project?
Quote
Dave was more complex for me as I haven't known how to synthesize noise by the mean of polynomial counter or make a distortion effects by the same means.
Yes, the synthesizer is the largest problem :-(

Offline IstvanV

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #7 on: 2008.July.30. 15:29:26 »
But not enought for the 100% compatibility :-(
In the hungarian forum, now we discussing about timing problems in the emulators. The ep128emu developed by the documentations, but now I found many difference about the memory and video memory access timing in the real and emulated machine.Wow! It is exist any documentations about this project?Yes, the synthesizer is the largest problem :-(
The video memory timing accuracy issues in emulators are mainly caused by not emulating the Z80 bus timing in a cycle accurate way (that is, knowing exactly what the Z80 does in every 4 MHz cycle; this could be emulated with sufficient information and/or extensive testing of the real hardware, although the emulation speed would be obviously reduced).
However, I did make many sound tests to reverse engineer the synthesizer in DAVE to have more complete information than what is available in the documentation, and this area is generally fairly accurate in ep128emu. It does emulate the filters, ring modulation, and polynomial counters (distortion and noise), and also the pseudo-random sequences generated by the polynomial counters should be reproduced correctly.

Offline Saint

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #8 on: 2012.September.24. 10:50:20 »
This topic is continued here...

http://enterpriseforever.com/hardware/enterprise_vhdl-t716.0.html

I don't think it should be too tricky to get Nick running, I'm starting to work on it now. Just figuring out how everything hangs together, then Nick will be the first chip I'll have a bash at.

Things like noise shouldn't be tricky for Dave either as you have chips like the YM2149/AY38910 with polynomial noise modelled in other projects (ST or CPC emulator). As long as Dave doesn't have any analogue stages like SID, then it shouldn't be too bad.

Getting them to be accurate enough and ironing out the bugs will be tricky, though. :)

Once anything is vaguely running on my Altera DE1, I'll create a sourceforge (or similar) project an opensource it.

James

Offline IstvanV

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #9 on: 2012.September.24. 12:37:12 »
Things like noise shouldn't be tricky for Dave either as you have chips like the YM2149/AY38910 with polynomial noise modelled in other projects (ST or CPC emulator). As long as Dave doesn't have any analogue stages like SID, then it shouldn't be too bad.

The sound generators in DAVE are already well emulated by ep128emu, and are documented here (in Hungarian). Perhaps the emulation code could be useful to get started with a complete model of the DAVE chip.

Offline Saint

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Re: One Chip MSX mkII - a chance for an Enterprise in FPGA?
« Reply #10 on: 2012.September.24. 12:51:03 »
The sound generators in DAVE are already well emulated by ep128emu, and are documented here (in Hungarian). Perhaps the emulation code could be useful to get started with a complete model of the DAVE chip.

Yes, the software emulation will be a great place to understand how the hardware works. Thanks for the link!

James