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usuario: can you please publish plans in English to HansO? Thanks a lot

Hi Adrian, it's a easy do it yourself:
http://msx.retro8bits.com/msxdocs/turbo7mhz.pdf
(schematics in page 3.) no translation is needed

how to built in(different msx models):
http://www.bas-ditta.info/verkoopenlinks/doehetzelf/7mhz.htm
in Dutch, a Dutch-English web translator will be enough

Hi ,
I was thinking in the limitation of the MHz due to the RAMs ROMs , going further than 8MHz look unstable and 2x3.57MHz= 7.14MHz
seems to be a perfect match , though slower.
I came to the conclusion that we need slow external BUS access between 3.5MHz and 8MHz and fast CPU inside , like 486DX266 processors.
This is possible only with the addition of cache memory, cahce memory is also 0 waitstate so you gain even more that the clock ratio.
A Z80 with cache and internal clock and external slower clock ?
IT EXIST(ED)
-> Z80280 MPU
as far as i can understand 80380 was not compatible with 280 , and has not cache memory.
the faster 280 is running at 12MHz and it accepts timings for external bus of 1/2 or 1/4 clock ratio.
So 12MHz cpu with 6MHz external bus is perfect match , with 1/2 ratio.
it has 256 +256 bytes of cache for instruction and data.

The only problem is the package PLCC68 , it needs a converter to DIP40...

more than 7.1 mhz

Z80 cartridge for EMSX system:
http://msx.deneb.nl/page1.HTM

EMSX:
http://msx.deneb.nl/page5.HTM

it is not comparable : these are more like mother boards and not turbo kit ! i am sure u know how to do the difference : in one case you end up with the same msx you had before but the cpu is replaced , in the other case you build a new computer from ground into a new case.
That is why you did not post these link in your previous message.
you cannot put these carts into regular msx , only lpe-Z380 could be and even in that case you have to rewrite the code to take advantage , it is not like doing all just like before but faster.
in that case you could even put a 33MHz Z180 also if we go that way

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it is not comparable :

why not? it's a question of speed

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these are more like mother boards and not turbo kit ! i am sure u know how to do the difference : in one case you end up with the same msx you had before but the cpu is replaced , in the other case you build a new computer from ground into a new case.

I know the difference, I've a EMSX(nice msx machine,you can build your own msx style) and other nice msx machines.

http://www.flickr.com/photos/44218601@N06/sets/72157622682682571/

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That is why you did not post these link in your previous message. you cannot put these carts into regular msx ,

I'm not saying it (I didn't write it, if I remember ^^!).

I'm sure I wrote in my last post "EMSX". You can read it.

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I was thinking in the limitation of the MHz due to the RAMs ROMs , going further than 8MHz look unstable and 2x3.57MHz= 7.14MHz

I put the example because EMSX is a msx computer running up 7mhz with a Z80 cpu.

my point was to go further 7MHz eventough legacy hardware cant work above, the poll is bout expansion , right it is written on the subject.
So the fact you can build a new computer from zero that runs 14MHz or above does not proove you can implement it into an old system.
EMSX is not a good example of an expansion that enable old system to run higher than 7MHz and the difference is not conceptual purism , the difference is $$$, a lot !

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my point was to go further 7MHz eventough legacy hardware cant work above, the poll is bout expansion , right it is written on the subject.

As I said, I answer your question about Mhz limitation, not other question:

• was thinking in the limitation of the MHz due to the RAMs ROMs , going further than 8MHz

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EMSX is not a good example of an expansion that enable old system to run higher than 7MHz and the difference is not conceptual purism , the difference is $$$, a lot !

EMSX is a modular MSX, you can easily change your hardware configuration (put/remove) hardware cartidges without hardware modification because it is (L.Padial slot expander based) and it's possible to use with it 16, 24 or 32 bits new hardware, PDA bus and DMA for using DSP,eZ80 or Z380 (possible linear memory addressing).

And about $$$... I'm sure you know build this kind of hardware is not cheap.

Try to do it yourself a Z380 cartridge.....

i said it is more expensive to build a complete new computer like emsx i never said it was overpriced wrt to what you get : you can read me twice.

i was not asking about Mhz limitation , i was try to find a new solution to Mhz limitation of old ram and roms.( 120ns and 150ns access time most of the time ) you talk about ez80 : to let it run full speed 50Mhz you need far less 20ns access time due wire and logic decode delays , this access time are not common for dram or sram inside 80's msx ...

aaaanyway i feel like i ll drop it

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i said it is more expensive to build a complete new computer like emsx i never said it was overpriced wrt to what you get : you can read me twice.

Sorry for misunderstanding

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you talk about ez80 : to let it run full speed 50Mhz you need far less 20ns access time due wire and logic decode delays , this access time are not common for dram or sram inside 80's msx ...

Yes I talk about eZ80 but EMSX running, now you must read me twice

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aaaanyway i feel like i ll drop it

I'm agree with you that main problem is it: old chips.
If you want to use new hardware with critical specs. you must change "all" parts from old msx.

nice options:

* EMSX: Modular MSX
* One Chip MSX

i can read on l.padial the list of emsx configs and card required for minimal working system, but i am curious about your emsx config :
what had to buy :
slot expansor
cpu card ( which one did you actually pick )
vdp card
what else ?
i see there is fdc card , but i am unsure it is interesting
to add floppy to a emsx ,
was it easy to hook up power to main board ?

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i can read on l.padial the list of emsx configs and card required for minimal working system, but i am curious about your emsx config : what had to buy :

Minimal EMSX System:
================
* Slot Expander
* VDP 9938/9958 card
* keyboard+RTC card
* CPU card
* GSB card

My EMSX System (now using):
=======================

* Slot Expander
* VDP 9958 card
* keyboard+2 serial+RTC+Parallel bidirectional port (MSX<->PC)
* CPU card
* GSB card (ROM+512k SRAM 20ns)
* LPE-SAN3-V1(SCC+PSG+FM_PAC+512k flash SCC+512k flash FM_PAC) card
* Sinfox V2.2 card or L.Padial SD card
* 2 empty slots for use other cards (4mb,gfx9000,moonsound,mp3...)

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i see there is fdc card , but i am unsure it is interesting to add floppy to a emsx ,

It's no needed using a SD card.

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was it easy to hook up power to main board ?

Yes, AT is ready to plug.
But I use a mini-ATX(adapted for me)

for bios rom's you use msx2+roms or msx2 ?
that gsb card is not clear or me , there are many versions not sure which one has ram rom and which one are needed for standalone emsx or not.
is it possible to build emsx with z380 card ?
at 14Mhz what is the score in dhrytones with this utility :
http://www.alsoftware.com.br/adrianpage/dhryston.lha
??

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for bios rom's you use msx2+roms or msx2 ?

msx2 with basic 3.0

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that gsb card is not clear or me , there are many versions not sure which one has ram rom and which one are needed for standalone emsx or not.

* gsb ram/rom/slot expander logic for EMSX
* gsb slot expander logic for stand alone use with msx computers

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is it possible to build emsx with z380 card ?

I've not z380, ask about it to L.Padial

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at 14Mhz what is the score in dhrytones with this utility : http://www.alsoftware.com.br/adrianpage/dhryston.lha ??

benchmark EMSX/msx machines/turboR was published some years ago. I don't remember where

Interestingly I compiled your test using HTC v 7.8PL2 and the result gives 24 Dhrystones.
The .com program in the package gives 23 Dhrystones (on the same msx configuration)

It can be a nice way to compare C compilers

you can download this version of dhryton , it has a pile of results in comments
http://www.democity.drn.digitalriver.com/free-download/General-Information/dhry0217zip/46826.html

i am puzzled by the fact that turboR rate 247 with dhryston v1.1 you just tried and pc-xt @4.77Mhz rate 271 to 423 with this code ... even 6510 @1MHz scores 36...

well compiler matters a lot looking at these results !
turboR looks 10x faster than regular Z80 tough .