Atari ST(E) DMA top speed, new, cheap CF adapter project

[Waltermixxx]

in the section on the cf interface http://atari.8bitchip.info/acsicfs.html there is a GAL file, but no JEDEC file available.
I'm trying to get more familiar with the whole GAL programming thing.  Will this file be made available,
so we can try and program our own chips?   Cheers.

[msolajic]

If you don't have a GAL programmer, you can find one's schematic over at http://elm-chan.org/works/pgal/report_e.html . There's also a link at the very bottom of a page to a GAL assembler, to convert the GAL to JEDEC.

[Waltermixxx]

Thank you, that is helpful.  I had been to that site before... did not realize you could assemble the gal file to create the jedec file... thank you

[Petari]

I will add jedec files. But as M. Solajic said you can use some GAL assembler to make them from GAL files.

[Waltermixxx]

Cool thanks for doing that...  I'm very very very new to these GAL devices, so any help is always appreciated.
I purchased the 74HCT245's and some of the other HCT chips, its always the physical connectors that cause
the problems eh?

cheers and thanks again.

[Arthur]

During weekend I did some improvements, driver.
So, now it works with Kingston 1GB too, for instance - only slower.
Can use together with another ACSI device - with some limitations.

More details, some pics here:   http://atari.8bitchip.info/astide.php

Second passus.

Hello Peter, is that my good old AdSCSI adapter from germany? ;o)


Regards

Arthur

[Petari]

Hello Peter, is that my good old AdSCSI adapter from germany? ;o)

Exactly :-)

[Petari]

Page is updated. Now there is PCB design for ACSI-CF adapter + driver. It works well on TT and driver supports TT Fast RAM too .

[Methanoid]

Will you be selling the populated or unpopulated boards at all?

[Petari]

At moment I can not deal with it. Maybe some months later. Of course, if someone wants to do it, no problems. In any case, will need my assistance + SW.

[Petari]

Original idea and project was to make very fast + very simple adapter.
Unfortunately, high speed works only with Sandisk cards, due to limitations of CF standard (btw. dumb limits, what Sandisk wisely followed not).
To achieve high speed with usual CF cards, we need few components more, but still, cheap ones. The point is that we need PIO mode, because then my work with 8-bit data width. But PIO mode coworks not well with ACSI port's DMA mode - simply, no initiator - IDE waits signal from host, while host waits DRQ from IDE. Solution is adding 9-bit counter + some logic. Then we can transfer sector data - 512 bytes in 512 steps - because 8-bit mode.
Another solution would be using latching and 2-step DMA R/W (similar like in Spectrum IDE IF), but I think that counter solution may be simpler.

Any people interested ?  I will not do it for myself - I love Sandisk 

[kovacm]

I think that SanDisk is not a problem - you can buy them everywhere and they are not expansive (2GB is a limit, right?)


did you find where you could make PCBs?
and do you know how many people would buy them? (make some poll on forum)

[Petari]

Limit is 128GB - if you have so much money for card 
There is one man in UK, who told that will produce this and PCBs. So far nothing available ..

[exxos_uk]

This seems like a great project. I am not sure what the status of it is ?

If the PCB is correct then I can get them produced.

I can program the GAL with my programmer (probably) , but I have no source for the D-sockets.

I think it also needs your own driver software ?  I am not sure if it possible to auto boot ? assume it will work ok in TOS104 ?

What about the DMA, will it work with the buggy one, or does it need updated DMA ?

[Petari]

PCB is correct. I don't know what you mean about no source for D-sockets ? You mean 19-pin Sub-D for ACSI port ? It is possible to order from some Asian sellers.
Adapter needs of course special driver SW. What I have. Autoboot works not without TOS mod. - it is normal, because it works not via standard ACSI protocol. I have code for it, what can be added to any TOS version. Without TOS mod is best to load driver from floppy AUTO folder.
Adapter and driver SW works fine in TOS 1.02 - 2.06 (1.04 min. is recommended).
I did not try with buggy DMA, what I have not, but it is to expect that will work bad, actually because high speed worse than usual adapters.