High density .STX / pastis support

[gwEm]

Short question : Should I expect high density STX files to work properly with Hatari

Long question : Kind of a weird question I know, but I am using AkaiSex with a high density STX image on Hatari.

I totally expected this not to work, but in fact it seems to be very close to working. There are numerous errors, but AkaiSex does correctly produce full directory information for the disk.

Interestingly, AkaiSex reports this is a double density disk, not a high density one.

[npomarede]

Hi
I was not aware that STX files existed in high density ; since pasti requires a 68000 STF/E for accurate cycle timing when analyzing protected disk, I did not know that a ST could read HD disk in that case.
Or maybe those HD STX files were not produced with pasti but with another tool ?

[gwEm]

Hi
I was not aware that STX files existed in high density ; since pasti requires a 68000 STF/E for accurate cycle timing when analyzing protected disk, I did not know that a ST could read HD disk in that case.
Or maybe those HD STX files were not produced with pasti but with another tool ?

they were produced with another tool. I have checked the Pasti file header, and it is correctly set as high density. 0xA0 for the number of tracks.

(edit : anyway, its not too hard of a modification to fit a high density drive in an STe, TOS 2.06 works well with them)

[npomarede]

Never having any example of an HD STX image, this is not supported in Hatari.
But 0xA0 doesn't mean HD disk for me, it means a 2 sided floppy with 80 tracks on each side, hence 160 tracks total.
An HD track should be be twice "larger" than the usual ~6 KB of data per track, but this shouldn't change the total number of tracks.

I think Ijor can comment on this and whether HD STX are sthg real or not.

Nicolas

[gwEm]

You say that, and you could well be right, it’s just my interpretation of the spec which says. It’s 80 or 160 for ‘double faced’ disks.

HxC software won’t generate high density images of any other ST format than STX interestingly.

Not pretending to be an expert here, just looking for the real facts!

[Eero Tamminen]

According to Wikipedia Atari Falcon & TT shipped with 1.44MB floppy drives, and TOS 2.x in Mega ST(e) devices also supported 1.44MB floppy drives. Wikipedia isn't clear on whether Mega ST(e) devices shipped with such drives though.

On ST one needed to buy HD drive oneself, do some soldering (1 NAND chip & few wires is enough) and run a program to set the double speed (6ms) stepping needed for accessing the HD floppy disks.

So, obviously there can't be any commercial ST games requiring HD floppy drive timings, but it's in principle possible that some commercial Falcon game might require HD floppy drive timings.

Most games of that era were already hard disk installable though, and expected to be such, so use of floppy timings as protection measure seems a bit unlikely to me. I haven't come across any such games or heard of them when testing things with Hatari Falcon emulation in last decade either.

[gwEm]

I have a Mega STe with a high density drive. Early ones shipped with double density, and later ones high density.

[gwEm]

Of course, it could easily be a problem with the HxC tool. But as I say, it very nearly works.

Edit: it does strike me as odd that HxC only supports high density for STX and not MSA or ST

[gwEm]

Would it help if I attached the STX file here? Someone could have a look and see if it is legit.

[npomarede]

Yes, you can post it and I will have a look (could take a few days, I'm rather busy at work at the moment)
By the way, why STX for this floppy image and not plain .ST ? Is this floppy protected ?

[gwEm]

I appreciate you taking the time to have a look.

The disk has started out on an Akai sampler with an HxC floppy emulator. I have taken the .hfe file and converted it using the HxC tools. The only Atari format that the HxC tools allowed for this image was .stx

The Atari program AkaiSex allows you to read the Akai disks and extract the samples. It works really well, and much better than a modern program I do believe. http://martin78.com/files/akai_s1000/akaisex-v1.26.zip

Using Hatari I have mounted the .stx file, and then loaded AkaiSex. The program recognises the disk and displays a directory, but generates errors when extracting the samples. Incorrectly, it says the disk is a DD disk, not an HD.

[ijor]

Pasti doesn't have "official" support for high density images. But nothing prevents you from encoding HD disks on Pasti format. In theory, the only thing that would be needed for full support would be some conventional flag marking the image as HD.

But even without such a flag, and just as it is now without specific support, the image might work depending exactly on the tool and the software. You certainly should be able to read all the sectors under emulation. The timing won't be accurate, of course, but probably you don't care.

I am currently on a trip and can't inspect the Pasti image. I don't know exactly why the software you are using doesn't work. Does it support HD disks at all? How the HFE image was created in the first place?

[gwEm]

The hfe was created on an Akai sampler.

The Atari software (AkaiSex) definitely supports HD disks, I used to use them back in the day.

Since my GEM format menu on Hatari doesn’t have the option to format high density disks, and there is no way to tell Hatari to emulate an HD drive, I do question wether Hatari supports HD disks at all

Should be an easy one to do.

[gwEm]

(Indeed I don’t care too much about accurate timing, I just want to read stuff off the image. It is tanatalisingly close to working.)

[npomarede]

So, I'll wait for Ijor to inspect the STX image you posted, maybe it doesn't work under Hatari because the image itself is flawed after the HxC conversion.
If Ijor confirms that the image is OK (timings apart), then I will look into Hatari code to see what is missing.

Nicoals

[gwEm]

It occurs to me it might not necessarily be on the Pasti support side, but in general support for high density drives. Anyway - we will see!

Thanks for looking at this gents.

[npomarede]

Hatari already handles 1.44 MB HD disks or even 2.88 MB ED disks in the sense that it will accept floppy images with 18 or 36 sectors per track instead of 9 for example, so I think it's really specific to this STX image.

[gwEm]

It’s funny though, because on MegaSTe mode, the HD drive is not emulated. TOS thinks it has a DD drive connected.

[npomarede]

Not all mega STe were produced with an HD drive, first ones were DD and Hatari emulates a DD drive (at least, I never looked into TOS code to see how it checks for DD drive or HD drive, could be an addition for next Hatari version, but I don't think it's related to your STX floppy image)

[gwEm]

There is a DIP switch on the real hardware at least

[Eero Tamminen]

Not all mega STe were produced with an HD drive, first ones were DD and Hatari emulates a DD drive (at least, I never looked into TOS code to see how it checks for DD drive or HD drive, could be an addition for next Hatari version, but I don't think it's related to your STX floppy image)

HW difference is that HD floppy drive needs double the clock to access HD floppy disks, and on the SW side one needs to set double the step rate (6ms instead of 12ms I think). On my STfm I had a program that runs from my hard disk AUTO folder that set the double step rate (after I had done the soldering to provide the double clock).

I assume that the dip switch does both of these things (SW side with TOS 2.x or newer based on some register value?).

[gwEm]

It’s probably where TOS 2.06 makes a decision about the HD floppy drive cookie and enables things like the HD floppy format option on the desktop.

[gwEm]

more playing

the .STX file works absolutely fine. the problem is that Hatari does not have an option to enable high density disks in Mega STe mode.

In TT and Falcon modes it works absolutely fine. Unfortunately the TT mode runs quite slowly on my Apple, but Falcon is ok.

If there could be a checkbox added somewhere to enable HD disks for TOS 2.06, I would be very grateful

[darwinmac]

more playing

the .STX file works absolutely fine. the problem is that Hatari does not have an option to enable high density disks in Mega STe mode.

In TT and Falcon modes it works absolutely fine. Unfortunately the TT mode runs quite slowly on my Apple, but Falcon is ok.

If there could be a checkbox added somewhere to enable HD disks for TOS 2.06, I would be very grateful

I think you may be confusing the option to format an HD disk with the ability to read an HD Pasti (STX) file. I tried to read your STX file with Hatari configured as a Falcon. It could not read the file. However, the format disk menu did give "High Density" as an option.

I think you will have to wait for npomarede and ijor to review your HD Pasti file. Ijor (the person who created the Pasti file format) mentioned there is no official support for HD images. However, it might still be a valid file.

You can create an ST image file in High Density from the "Create Blank Floppy" menu item in the File menu (since you are running the macOS version of Hatari). That image is successfully read in Hatari even in TOS 1.04.

However, since it appears you only have the ability to create a Pasti (STX) file from your software, it may require additional work in Hatari to support such an image (if the STX image is seen as valid).

Bob C

[gwEm]

Thanks for the reply, but there is no mistake here.

That image definitely works if you use the AkaiSex program. However, it won’t work if you read it using normal Atari methods that’s for sure.

I transferred several Akai disks using Hatari and high density STX files last night. Absolutely it works.

However, I can only do this in TT or Falcon mode. With the 68000 ST modes, although may support HD disks images, TOS 2.06 does not recognise there is an HD drive fitted to the emulated machine. This is causing problems with the AkaiSex program.

I’m not being crazy..