68000 CPU Accelerator on STE?

[projectwoofer]

Hello to all!

Please excuse my ignorance but sometime ago I came across this accelerator which originally came for Mac but also features a 16 MHz 68000 CPU (with cache?) and it reminded me of the ICD AdSpeed Accelerator...anyone ever used this to speed-up an ST? Of even if it did do the job, it will probably need some kind of drivers maybe? As the accelerator boards for the ST are becoming more and more rare, I just wanted to check if these would work...any ideas?

Some info about the Brainstorm Accelerator: http://lowendmac.com/benchmarks/brainstorm.html

[karlm]

In theory if all it did was replace the cpu with a faster clocked one and the cache was directly interfaced to the acutal cpu, and it had it's own clock generator, not trying to pick it up from the system ... it could work. A lot of the Amiga accelerators (the 16mhz 68000s) did this and were basically usuable on both Amiga and ST.
This type of accelerator for the Mac will not work however because the cpus in those low end macs were DIL type chips whereas the STe is PLCC iirc. This is why you see those ide interfaces for ST or STe. It may work in a bog standard ST though.
Bear in mind though a lot of games etc and some apps will not work with this - they are expecting certain timings etc.

Worth investigating though.

[projectwoofer]

This type of accelerator for the Mac will not work however because the cpus in those low end macs were DIL type chips whereas the STe is PLCC iirc. This is why you see those ide interfaces for ST or STe. It may work in a bog standard ST though.

Yes, you're right...I didn't notice that it was a DIL type...

[simbo]

hi

you need to add a chip to allow 16 mhz operation
if you just plug it in it wont work at 16mhz but just still 8mhz and a 16mhz chip
follow the circuit and add the logic chip you need also
if you need further direction just use pm link and send me skype or msn info
and i can help in vidaud

http://atari4ever.free.fr/hardware/speed.html

see 16mhz_st.zip

i used altavista translate {blblefish}
and the circuit in the picture in the archive
i used paint shop pro or you can use the atari or steem to view it

dead easy to add,.,, simple four or five solders and a wire,,,!!!

[projectwoofer]

hi

you need to add a chip to allow 16 mhz operation
if you just plug it in it wont work at 16mhz but just still 8mhz and a 16mhz chip
follow the circuit and add the logic chip you need also
if you need further direction just use pm link and send me skype or msn info
and i can help in vidaud

http://atari4ever.free.fr/hardware/speed.html

see 16mhz_st.zip

i used altavista translate {blblefish}
and the circuit in the picture in the archive
i used paint shop pro or you can use the atari or steem to view it

dead easy to add,.,, simple four or five solders and a wire,,,!!!

Thanx Simbo!

Will check the schematics ASAP! Is this document about an STE or an ST(FM)? Does it contain a cache for the CPU?

Moreover, I wonder what is happening in terms of software compatibility on a STE (which I own) with and without a 16MHZ CPU accelerator (with cache or not...?)

[simbo]

i think its the same mpu just runs upto 16mhz it may have slight improvements in the dia etc
i assume you have a 40pin dil 16mhz 68000???? usualy an ST68000
then the machine should run exactly as it is just process a little faster {twice as fast}
so will appear smoother
the cicuit is just a clock doubler and dtack generation to enable 16mhz clocking
to the 68000 you added
or it will still just run with an 8mhz clock
software not sure i dont see it being a problem
you can add a switch to run it in 8mhz mode

[karlm]

i think its the same mpu just runs upto 16mhz it may have slight improvements in the dia etc
i assume you have a 40pin dil 16mhz 68000???? usualy an ST68000
then the machine should run exactly as it is just process a little faster {twice as fast}
so will appear smoother
the cicuit is just a clock doubler and dtack generation to enable 16mhz clocking
to the 68000 you added
or it will still just run with an 8mhz clock
software not sure i dont see it being a problem
you can add a switch to run it in 8mhz mode

Yes all it does is add a 16mhz feed into the 68000 instead of the usual 8mhz. No cache. If you are going to do it, add the 8mhz switch as most games (unless fixed to run at >8mhz) will have problems, and also some untidy programmed apps. Also as the cpu is going to be run outside it's specs, better look st some cooling like a cpu fan ...

I don't know about anyone else, but I've never seen a STe with a DIL CPU though ...

cheers

karlm.

[simbo]

you do get them 16mhz dil 68000 16mhz made by just a few not so big scale

they were for the mac world mostly and require no heatsinking...

but youll ..i agree find little use unless you do one thing like word process
then it get's there a little faster if youve got a blitter
good for cubase im sure...

for me there is just two worlds

games <> software...
software <> games

they are not the same at all...!!!!

[Shredder11]

Mmmm....I have often wondered if this 16MHz chip and cache works properly and is worth it. I started out by only using my STe for Cubase, Fast Copy Pro 3 and a few other minor applications. During the year 2000 after five years of doing this, I started to become curious and began playing games, word processing, using module based programs like Look 'n See to open up all kinds of stuff, plus I began doing photo stuff with Speed Of Light, Photochrome 4 etc.

So maybe this 16MHz chip and cache is worthwhile for me too? I now have three STe machines with the best one having an IDEal IDE interface, IBM 2.5" 720MB drive, TOS 2.06 UK, 4MB RAM, Cumana 1MB external floppy, VGA Mono adapter, RGB to SCART, Horizon 16ch MIDI expander etc.

[synthetic242]

I once bought an accelerator for my STE called T28. There also exist a T36 accelerator.
28Mhz vs 36 Mhz.
As I remember I had to lift off the CPU and place this new board into the socket,
solder some cables and also a speed-switch and cache-switch so I can go down to 8Mhz
with full compability mode.
With cache turned off it was not much faster than 8Mhz mode even run in 28Mhz, but with it on, oh hell,
that's fast.

The only sad thing is that Midex+ from Steinberg was not compatible with it, first note was played when
it hangs, not the computer but the MIDI out.

I sold this 4MB STE with T28 + 1.44MB 3.5" and 250MB harddisk when I bought my first Falcon030
with...some accelerator and a lot of extra stuff.

[exxos]

I still have some 16mhz DIL CPUs left if anyone is after them. I was playing around with this a while ago, I clocked a ST to about 12mhz, though that was the entire 8mhz bus, everything screwed up, but I don't think I got around to trying a 16mhz CPU. Really it needs faster RAM and then double clock the MMU... Though I wasn't so sure if the MMU would cope being double clocked.. plus then there was video timing problems... was turning into a bit of an epic unfortunatly

[ozy2000]

Blast from the past!!

Well really I could do with a 16mhz machine...and not an STE just a bog standard ST (not even STF/STFM). I remember two 16mhz boards for the ST and all they did was run the CPU @ 16mhz on the daughterboard with logic to filter that down into the standard video/mmu timings etc so effectively like a Centrino processor (clock doubled so double the execution cycles)

If anyone has a slightly more simple way of doing this (ie more simple than the diagram linked to already...or with some more details or even some instructions in english) I would be most greatful...whilst I CAN hold a soldering iron...I am NOT an electronics whiz

[coze]

doubling the clock speed of the processor will not give you a speed boost if the processor has to wait to fetch the the next instruction from a slow ram. that's why all 16 MHz accelerators and ST models (Mega ?) have cache on them. If you can't also add a cache in it, I say don't bother ... (also there's always the possibility of cache messing up software compatibility ...)

[ozy2000]

I think the best reported speed increase from a dedicated ST 16mhz upgrade card for the old ST/STM/STFM was about 30% approx yes, don't know about how good the Mega STE 16mhz mode is as mine was stuck in mono mode (and nearly fried my SC1224!!) so couldn't try any games at the time (and sold it to someone who could fix it).

[wongck]

I think the best reported speed increase from a dedicated ST 16mhz upgrade card for the old ST/STM/STFM was about 30% approx yes, don't know about how good the Mega STE 16mhz mode is as mine was stuck in mono mode (and nearly fried my SC1224!!) so couldn't try any games at the time (and sold it to someone who could fix it).

I used to own a megaST4 with 16MHz cpu with an internal HDD. I was using it on a TV and works fine. no mono mode for me as I did not afford a monitor and used it on my TV. That was mid 90s.

[AtariMega125]

I think the best reported speed increase from a dedicated ST 16mhz upgrade card for the old ST/STM/STFM was about 30% approx yes, don't know about how good the Mega STE 16mhz mode

I just recently benchmarked a Mega 4 with a Turbo16 accelerator compared to a Mega STE. The speed increase is close to 100% with the cache enabled on both systems. The Mega STE is just a hair faster on graphics functions but just about the same on CPU tests. With the cache enabled, the speed is doubled for most things on both systems.

I've ended up removing the Turbo16 from the Mega 4 because the accelerator was totally incompatible with Clab Notator.

[wongck]

Here's a good read on CPU accelerators - The Quest for Speed