New disk image format STW

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Re: New disk image format STW

Postby Steven Seagal » Sun Jul 13, 2014 10:30 am

The best copier seems to be the latest ACopy.
I found something strange about ProCopy: all versions use $A1 to write sectors, so they're all marked as 'deleted records', and some copies fail because of that. I propose we call it AmateurCopy now. :)

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Re: New disk image format STW

Postby Dio » Mon Jul 14, 2014 6:56 am

Personally I think this is a wrong turn.

I believe the solution to emulating all floppy commands is to have an IPS or .ST file as the main disk image, with a small associated overlay (contained in a separate file) which defines a set of overrides of the data to be applied when converting the track image into the input to the FDC. These overrides would consist of the appropriate tracks written, and the sector data written with the appropriate write command and timing information to allow it to be merged in at track generation time.

I've mentioned this plan to Istvan in the past for support in the CAPS FDC, but I don't know if they've yet done any implementation on it.

The key advantages of this system are:
- Efficient use of space as only deltas are kept
- Multiple overlays can reference the same base disk without wasted space
- Base disk remains write-protected at all times and so is known to be a pristine copy of the original
- Simple to implement

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Re: New disk image format STW

Postby IFW » Mon Jul 14, 2014 9:35 am

Actually, we were thinking about it, but then all of these save formats started to appear, so...

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Re: New disk image format STW

Postby npomarede » Mon Jul 14, 2014 12:49 pm

Actually, that's what I used in latest hatari : I record each write sector or write track in a .wd1772 file which works as an overlay like dio described (but only for .stx at the moment)
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Re: New disk image format STW

Postby Steven Seagal » Mon Jul 14, 2014 6:13 pm

It's all explained here, I can't repeat the same all the time:

http://ataristeven.t15.org/Steem_370_coming_soon.htm

http://ataristeven.t15.org/Steem_370_coming_soon2.htm

STW disks are NOT ghost disks.

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Re: New disk image format STW

Postby dlfrsilver » Sun Jul 20, 2014 2:02 pm

Congrats Steven for both disk formats ! Ah it's good to see the disks operations being done as on the real machine :) yay !!!
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Re: New disk image format STW

Postby DrCoolZic » Mon Dec 15, 2014 6:36 pm

Jeff_HxC2001 wrote:The HxC AFI format have all these missing datas, but the format is harder to handle : data chunk are gzipped to keep the file size small and all protected with CRCs… And I don’t have documented it yet ;)

Is this used in current HxC or is it for future :)

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Re: New disk image format STW

Postby Jeff_HxC2001 » Thu Dec 18, 2014 11:27 pm

DrCoolZic wrote:
Jeff_HxC2001 wrote:The HxC AFI format have all these missing datas, but the format is harder to handle : data chunk are gzipped to keep the file size small and all protected with CRCs… And I don’t have documented it yet ;)

Is this used in current HxC or is it for future :)


Current HxC software.

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Re: New disk image format STW

Postby Retrogamer_ST » Tue Dec 23, 2014 10:20 am

A stupid question?

If you use TOS 1.02, and choose the "Mega ST" option in Steems SSE tab, you will run TOS 1.02 and take advantage of the blitter chip found in all the MEGA ST models, right?

And a small request that should be quite simple to implement for a future update perhaps?

A dark theme, like in the Stella emulator for Atari 2600.

Image

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Re: New disk image format STW

Postby Steven Seagal » Wed Dec 24, 2014 11:56 am

@Retrogamer_ST

Wrong thread dude!

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Re: New disk image format STW

Postby Retrogamer_ST » Wed Dec 24, 2014 12:43 pm

Sorry about that. Looking forward to download STeem 3.7.0 when it's time for release.

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Re: New disk image format STW

Postby Steven Seagal » Wed Dec 24, 2014 2:42 pm

Keep it for yourself (:oops:) but it should be released end February, like last year.

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Re: New disk image format STW

Postby DrCoolZic » Sun Jan 18, 2015 4:11 pm

I will not comment on the fact that we are adding more and more formats
So now we have STT STG and STW specific for Steem an WD1772 for Atari ... would be nice to stop adding more format but ....

But one thing puzzles me in this format: usage of 16 bits data + clock ?
is it MFM or really data + clock ?

If this is data + clock it does not make sense?
If this is MFM then you are opening the door to a lot of trouble. Decoding MFM stream as the WD1772 does is very very tricky. 99% of the bit sequence are easy to decode but the remaining 1% is pretty hard.
Are you sure you will be able to handle all the cases? and most importantly for what benefit? When you write the MFM information you probably must have a pretty good idea of how it will be read and in that case why not write what you are suppose to read just using data?

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Re: New disk image format STW

Postby Steven Seagal » Sun Jan 18, 2015 6:02 pm

DrCoolZic wrote:I will not comment on the fact that we are adding more and more formats
So now we have STT STG and STW specific for Steem an WD1772 for Atari ... would be nice to stop adding more format but ....


There was nothing as straightforward as STW. HFE, STX, IPF etc. are horribly complicated. Something was missing, that's all. I published those simple formats so that they be not specific for Steem, after that people do what they will. In fact 'WD1772' came later. I thought that maybe Hatari would use 'STG' too.


But one thing puzzles me in this format: usage of 16 bits data + clock ?
is it MFM or really data + clock ?

If this is data + clock it does not make sense? If this is MFM then you are opening the door to a lot of trouble. Decoding MFM stream as the WD1772 does is very very tricky. 99% of the bit sequence are easy to decode but the remaining 1% is pretty hard.


It is MFM but the bits are just put together word by word.

Are you sure you will be able to handle all the cases? and most importantly for what benefit? When you write the MFM information you probably must have a pretty good idea of how it will be read and in that case why not write what you are suppose to read just using data?


For fun.
Notice that STW is supposed to only handle what the ST itself could do. It endeavours to offer complete emulation of WD1772 + standard drive, nothing more.
If you know more cases please report them.

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Re: New disk image format STW

Postby DrCoolZic » Sun Jan 18, 2015 8:00 pm

I am currently working on overlapped sync marks and documenting. But it is hard to generate the test cases

But apart from fun why do you prefer MFM compare to simple data only.
At the end the wd1772 send DATA ONLY information to program. There is absolutely no way to read MFM information from WD1772
So why would an image need to contain this.

If you really want details then there is the other images format you talk about

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Re: New disk image format STW

Postby Steven Seagal » Sun Jan 18, 2015 9:19 pm

DrCoolZic wrote:I am currently working on overlapped sync marks and documenting. But it is hard to generate the test cases

But apart from fun why do you prefer MFM compare to simple data only.
At the end the wd1772 send DATA ONLY information to program. There is absolutely no way to read MFM information from WD1772
So why would an image need to contain this.

If you really want details then there is the other images format you talk about


Yeah... are you some troll or what?

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Re: New disk image format STW

Postby Maartau » Sun Jan 18, 2015 9:26 pm

Steven Seagal wrote:The best copier seems to be the latest ACopy.
I found something strange about ProCopy: all versions use $A1 to write sectors, so they're all marked as 'deleted records', and some copies fail because of that. I propose we call it AmateurCopy now. :)


I'm not so surprised, even by the past, I always asked myself what could serve AmateurCopy ( :lol: ).

And totally agree with the fact that the best copier seems to be the latest ACopy.
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Re: New disk image format STW

Postby Steven Seagal » Wed Jan 21, 2015 8:28 pm

Maartau wrote:
I'm not so surprised, even by the past, I always asked myself what could serve AmateurCopy ( :lol: ).

And totally agree with the fact that the best copier seems to be the latest ACopy.


And yet I found that AmateurCopy could copy disks that ACopy can't, at least in STW.
But who cares about STW anyway?

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Re: New disk image format STW

Postby Jeff_HxC2001 » Wed Jan 21, 2015 8:44 pm

Is the STW format specification ready ? Where i can found the latest one ? :)

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Re: New disk image format STW

Postby Steven Seagal » Wed Jan 21, 2015 9:08 pm

Jeff_HxC2001 wrote:Is the STW format specification ready ? Where i can found the latest one ? :)


I think the specification in the first post is up-to-date.
There are some disk images here (not working with current version of Steem, you need the beta):

http://ataristeven.t15.org/Steem_370_coming_soon2.htm

If you add the STW format to HxC it would be much appreciated as there are many detractors for the moment and it could prove useful to transfer some images between Steem and real ST... for instance the famous Union Demo.

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Re: New disk image format STW

Postby Jeff_HxC2001 » Thu Jan 22, 2015 7:26 am

Steven Seagal wrote:
Jeff_HxC2001 wrote:Is the STW format specification ready ? Where i can found the latest one ? :)


I think the specification in the first post is up-to-date.
There are some disk images here (not working with current version of Steem, you need the beta):

http://ataristeven.t15.org/Steem_370_coming_soon2.htm

If you add the STW format to HxC it would be much appreciated as there are many detractors for the moment and it could prove useful to transfer some images between Steem and real ST... for instance the famous Union Demo.


Done ! :D

http://hxc2001.com/download/floppy_driv ... t_beta.zip

You can now read & write STW files with the software . (and then convert them to/from others format).

Note: The MAC build is not done yet, no time to switch on my Mac Mini this morning. I will do this this evening

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Re: New disk image format STW

Postby DrCoolZic » Thu Jan 22, 2015 8:28 am

Jeff_HxC2001 wrote:
Steven Seagal wrote:If you add the STW format to HxC it would be much appreciated

Done ! :D

Thanks Jeff great news

Steven Seagal wrote:... the STW format ... there are many detractors for the moment ...

Don't get me wrong I think this is a great idea to have the STW format. I was just asking question about usage of MFM.
What I was mentioning is that working at the bit level is a lot of work to decode properly. But after looking at your spec again it does not seems that you intend to do that anyway.
If I understand correctly you write ALREADY aligned MFM words (i.e. you wont take half of the bits from one word and half from next word - as done when doing bit decoding) and therefore this should make your life easy :)

Internally Aufit store with each byte a lot of information including the original MFM associated. So I might also write STW files :mrgreen:
Is there a prebuild beta of Steem accessible somewhere?

For your information the link for Realm of Trolls http://ataristeven.t15.org/STPRGS/Realm ... 20-DBG.zip is broken (too bad)

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Re: New disk image format STW

Postby AtariZoll » Thu Jan 22, 2015 9:05 am

Just my very biased comment about all troubles and complications here: isn't simpler to forget all this prehistoric floppy hassles, and making hard disk fixes of games :mrgreen:
Not just a joke - I see that lot of work is needed to emulate and/or support copy of some very strange and rare protection, format, and all that because only 1 title. That can be overridden by analyzing code, and redirect read/write to hard disk. Especially useful with multifloppy titles.

Yes, I know, you want originals intact. But I'm not really much respectful, to be honest, after all crap saw in last years. At least some titles don't deserve to be copied 100% faithful - because bugs, lack of testing. There are some lists here and there, and number is probably bigger than count of protection types 8O
Negative feedback has usually positive effect.

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Re: New disk image format STW

Postby AtariZoll » Thu Jan 22, 2015 9:09 am

DrCoolZic wrote:...
For your information the link for Realm of Trolls http://ataristeven.t15.org/STPRGS/Realm ... 20-DBG.zip is broken (too bad)


it seems as D-Bug crack.
Here is what is available of it: http://atari.8bitchip.info/ASTGA/R/realmtr.php
That's based on Automation crack - as only available of this game, but with some improvements.
Negative feedback has usually positive effect.

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Re: New disk image format STW

Postby DrCoolZic » Thu Jan 22, 2015 9:30 am

AtariZoll wrote:
DrCoolZic wrote:...
For your information the link for Realm of Trolls http://ataristeven.t15.org/STPRGS/Realm ... 20-DBG.zip is broken (too bad)


it seems as D-Bug crack.
Here is what is available of it: http://atari.8bitchip.info/ASTGA/R/realmtr.php
That's based on Automation crack - as only available of this game, but with some improvements.

MSA? Thought it was protected? Not STX?


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