At zilog.com I saw that there is a z80 at 20 MHz.
Why has nobody tried to implement this hi-speed z80 into an MSX computer?

There are 6 and 7 mhz extentions for MSX. Why not a 20 mhz extention?

Furthermore, what are the problems for implementing a new CPU like eZ80 of z180 (oka, not so new, but faster then z80 )?

For other computer systems(c64) there are speedups available, why almost none for MSX?

I find the padial hardware not interesting because it to expensive, but a extention board with a cheap z180 or ez80 could be interesting, or not?

I look forward to your reactions

greetzz

Padial, Sunrise and Ademir from Brazil hae projects based on z380 and Ez80I can say that the EZ80 can be obtained as 20 mhz and 50 mhz
Look at : www. msx.ch for our project the ethernetcard and lpdial.aamsx.org amd I donot now exactly the page opf ademir -if someone want to add-
The Z380 will be limited at 20 mhz and not 33 mhz because Zilog has no plans in short term to upgrade to 33 mhz.

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Why has nobody tried to implement this hi-speed z80 into an MSX computer?

The MSX-Engine chipset can't handle speeds higher than 10MHz, the VDP can't handle high speeds, even a 7MHz extension needs to be switched back to 3.5MHz during VDP access.

MSX cartridge devices (RS232, IDE/SCSI, soundcards, etc) can't handle the higher speed either. The system RAM would be far too slow too, so that must be replaced by new/fast/expensive chips.

An upgrade like this would need pretty complicated circuitry to switch back to acceptable clock speeds for the various MSX devices, while analyzing the instructions the Z80 recieves. Even 7MHz kits are only possible because of a special ZiLOG switchchip.

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Furthermore, what are the problems for implementing a new CPU like eZ80 of z180 (oka, not so new, but faster then z80 )? [quote]For other computer systems(c64) there are speedups available, why almost none for MSX?

MSX turboR (R800 is REALLY fast), several 7MHz kits, LPE-Z380 (18MHz, 32 bit)
Why do you say 'almost none'? For c64 there is only ONE speedup available, and it was released many years later than the first MSX speedups.

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I find the padial hardware not interesting because it to expensive, but a extention board with a cheap z180 or ez80 could be interesting, or not?

As stated above, the amount of modifications needed will make this very expensive, not cheap at all.

I understand that the msx-engine and other parts cannot run @ 20 Mhz, but isn't it possible to use some sort of clock divider (18/5 maybe?) so that the z80 runs at a much higer frequency then the other parts. The performance will be influenced but i think it'a better then 7 MHZ, or not?
Or use a Zilog switch chip that you mentioned?

Yes, I know, I don't have a clue

Okay, shame on me..I forgot the Turbo R...

I also understand that these modifications cost money, but choosing a expensive CPU like z380 won't help selling speedups. Why not use a z180 @ 20-33 mhz?

Or even a eZ80 @ 50 Mhz? This CPU costs aprox 15-20 euros and is really fast and a lot cheaper then a z380 (100 euro or more for a z380, I think). I think it should also be easier to implement a less complex CPU (like z180 or ez80) compared to a Z380.

I would buy a speedup or a new MSX board for 100-250 euro but not Padial harware for over 1000 euro (okay, a little over the top, but you got my point).

Z80 @ 20 Mhz costs aprox 15 euros, so (if techical possible) a speedup set like the 7Mhz sets would cost maybe..what?...40-60 euro?

I find it frustrating that there are a lot faster z80 compatible CPUs that are not powering my beloved MSX.

Why not use an emulator on a very fast computer?

I don't think it's usefull to make a z80-based system at 500MHz or something. I have a 7MHz upgrade, and I almost never use it, it isn't that much faster...

But if I would want a z80-based computer, it would be with the z380. It's 16bit instead op 8bit, and has more registers, and is new to me => more fun to program...

Why do we need such a upgrades? I think that the whole point of this retrocomputing thing, is that we stick with features given in the computer itself. Programmers of these 8-bit machines get very nice results with 1mhz (c-64) or 3.5mhz (z80) . If you wanna go fast, then use your 3.5ghz PC.

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Why not use an emulator on a very fast computer? I don't think it's usefull to make a z80-based system at 500MHz or something. I have a 7MHz upgrade, and I almost never use it, it isn't that much faster... But if I would want a z80-based computer, it would be with the z380. It's 16bit instead op 8bit, and has more registers, and is new to me => more fun to program...

Nahh..I want a real msx computer...not a emulator..

Well, I think if there is no performance gain when a faster z80 (20Mhz for example) is implemented in a MSX2(+) then your'e right..

But do you really think that a new msx-system with specs like: eZ80 50 Mhz, VDP (at least 10 times as fast as currect VDP), USB and IDE is not usefull?

If that kind of system cost not more then 200 euro I think that a lot of MSX fans will buy this board.

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I understand that the msx-engine and other parts cannot run @ 20 Mhz, but isn't it possible to use some sort of clock divider (18/5 maybe?) so that the z80 runs at a much higer frequency then the other parts.

The clock signal not being 3.58MHz is not the biggest problem. Another problem is the speed at which the I/O communication with these devices is taking place. For a 20MHz Z80 all programs must be rewritten to include delays for I/O access, or use a chip to do it. In a turboR there is such a chip. The S1190 Bus Controller sees if the R800 is trying to access the VDP, and then inserts delays.
Creation of such a Bus Controller is not trivial and expensive.

Also, the problem of RAM remains, and a 20MHz Z80 will only approximately be as fast a R800.

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I also understand that these modifications cost money, but choosing a expensive CPU like z380 won't help selling speedups. Why not use a z180 @ 20-33 mhz?

A Z180@33MHz is only marginally faster than a Z380@18MHz at executing Z80 code, and a Z180@20MHz is even slower than a Z380@14MHz!
The Z380 has the added advantage of 32 bit registers and addressing, and a full 16 bit instruction set, it's really much more powerful.

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Or even a eZ80 @ 50 Mhz? This CPU costs aprox 15-20 euros and is really fast and a lot cheaper then a z380 (100 euro or more for a z380, I think). I think it should also be easier to implement a less complex CPU (like z180 or ez80) compared to a Z380.

Sunrise is currently using an eZ80 in their ethernet-board for MSX. Apparently its features are not limited to ethernet only, although like Z380 it's not a direct replacement.

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Why not use an emulator on a very fast computer? I don't think it's usefull to make a z80-based system at 500MHz or something. I have a 7MHz upgrade, and I almost never use it, it isn't that much faster...

Not much faster? It is 100% faster except for accessing the v99x8 and the disk drive everything else is 100% faster

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>>Why not use an emulator on a very fast computer? I don't think it's usefull to make a z80-based system at 500MHz or something. I have a 7MHz upgrade, and I almost never use it, it isn't that much faster... << Not much faster? It is 100% faster except for accessing the v99x8 and the disk drive everything else is 100% faster

100% faster isn't much faster. I have some pc's at home and my fastest pc doesn't feel over 20 times faster than the slowest.
And most programs use the videochip or the disk drive. This makes a 7MHz MSX (except the turbor of course) not twice as fast as a normal MSX. Things will be even worse when the cpu is faster... I don't think there is a lot of software that would benefit from a speed increase. Well, maybe Basic...
And to benefit from the z380 you have to use software that was written for the z380.

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And most programs use the videochip or the disk drive. This makes a 7MHz MSX (except the turbor of course) not twice as fast as a normal MSX.

Hello?! HARDDISK! Accessing HD/CompactFlash at 7MHz is definitely twice as fast.

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Things will be even worse when the cpu is faster... I don't think there is a lot of software that would benefit from a speed increase. Well, maybe Basic...

LOL
Development tools, graphics tools, games (Solid Snake and SD-Snatcher being great examples), etc etc...

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I have some pc's at home and my fastest pc doesn't feel over 20 times faster than the slowest. And most programs use the videochip or the disk drive. This makes a 7MHz MSX (except the turbor of course) not twice as fast as a normal MSX. Things will be even worse when the cpu is faster... I don't think there is a lot of software that would benefit from a speed increase. Well, maybe Basic... And to benefit from the z380 you have to use software that was written for the z380.

for example meridian, benefits greatly from 7.16Mhz,actually almost every program benifits from it except maybe some interrupt timed games and demo's.
Or even the DIR command in dos. it is so slow on 3.54Mhz

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>>And most programs use the videochip or the disk drive. This makes a 7MHz MSX (except the turbor of course) not twice as fast as a normal MSX.<< Hello?! HARDDISK! Accessing HD/CompactFlash at 7MHz is definitely twice as fast.

Owjah! Harddisk! That solves the vdp slowdown

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>>Things will be even worse when the cpu is faster... I don't think there is a lot of software that would benefit from a speed increase. Well, maybe Basic...<< LOL Development tools, graphics tools, games (Solid Snake and SD-Snatcher being great examples), etc etc...

Don't forget to mention Sonyc, unplayable with MoonSound with 3.5MHz...
Still, I don't develop on msx (anymore), and I'm to slow myself to notice that graphic tools work faster. Conversiontool work faster, pack and unpack tools work faster...
And come to think of it, I probably played Solid Snake and SD-Snatcher on 7MHz... Took me half the time to complete these games

I didn't state it wasn't faster, I just said 7MHz isn't twice as fast, and I didn't find much use for it.

7MHz is ALWAYS twice as vast, EXCEPT when using the FTP.

So using harddisk/compactflash, compiling sources, unpacking LZH or PMA files etc. all go twice as fast. What's wrong about that.

About the fast MSX topic: we're all forgetting the slowly progressing CIEL3++ project here. Ultimate MSX

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>>I have some pc's at home and my fastest pc doesn't feel over 20 times faster than the slowest. And most programs use the videochip or the disk drive. This makes a 7MHz MSX (except the turbor of course) not twice as fast as a normal MSX. Things will be even worse when the cpu is faster... I don't think there is a lot of software that would benefit from a speed increase. Well, maybe Basic... And to benefit from the z380 you have to use software that was written for the z380.<< for example meridian, benefits greatly from 7.16Mhz,actually almost every program benifits from it except maybe some interrupt timed games and demo's. Or even the DIR command in dos. it is so slow on 3.54Mhz

Well, I have some experience with Realfun on 7MHz and it's only noticeble faster on the blockfunctions (which already are very fast en well optimized and good coded, of course 8) ). Still this speed up isn't useful here. But maybe Meridian with it's user interface benefits more from 7MHz...
A lot of programs run faster, but when userinput is needed or it's interrupt driven, than the speed up is mostly useless.

But it may be too long ago since I actually touched a MSX to do something with it other than testing some stuff I recently coded... To see it runs also on MSX, and not only on the emulators...