Creating your own IPFs

[dlfrsilver]

Thanks !

[Snoopy1234]

disk-utilities (analyse) a995b21 doesn't make a usable ipf of working Chaos Strikes Back (FTL) v_3.3.scp

Link to scp image: http://ftp2.grandis.nu/turran/FTP/~U...(FTL).v3.3.rar

[BarryB]

Run the SCP though disk-utilities again and create another SCP file from it, then put the new SCP through disk-utilities again and create an IPF from it!

This was Keir's advice when he was doing Dungeon Master, it cleans up the SCP file prior to creating the IPF.

[Snoopy1234]

Originally Posted by BarryB

Run the SCP though disk-utilities again and create another SCP file from it, then put the new SCP through disk-utilities again and create an IPF from it!

This was Keir's advice when he was doing Dungeon Master, it cleans up the SCP file prior to creating the IPF.

Ok Thanks I'll give it a try.

[Snoopy1234]

Still No Dice. Disk-analyse hasn't created a working replica of the csb_v.3.3.scp with --format option or without. No ipf either.

[BarryB]

The SCP might be bad or DU doesn't yet support CSB? Checking my 2 Kryoflux dumps of CSB they also fail to load so it might not be supported for emulation like DM was?

I've emailed Keir for clarification!

[acd2001]

keirf disk-utilities 2023-01-29 git ef2af52
Dungeon Master, Chaos Strikes Back: Fix GAP3. Should be 41 bytes, not 40.
Fixed CSB protection check.

[BarryB]

Originally Posted by acd2001

keirf disk-utilities 2023-01-29 git ef2af52
Dungeon Master, Chaos Strikes Back: Fix GAP3. Should be 41 bytes, not 40.
Fixed CSB protection check.

Keir kindly updated disk-utilities for Chaos Strikes Back

As CSB is really difficult my characters from DM are pathetic and die too quickly, so if someone has better characters can they be tested on the new update of disk-utilities?

My version of CSB is v3.5 from the Psygnosis release! Uploaded the IPF's to the Zone!!

[Keir]

If both DM and CSB IPFs now work, could someone please upload them to the File Server (or whatever it is now -- Turran FTP?) as Unofficial IPFs?

[TCD]

If somebody can confirm they work I'll gladly add them to the unofficial IPFs on 'the server'

[BarryB]

Originally Posted by Keir

If both DM and CSB IPFs now work, could someone please upload them to the File Server (or whatever it is now -- Turran FTP?) as Unofficial IPFs?

Are these still only for emulation use, not writing back to real disks?

[Keir]

Originally Posted by BarryB

Are these still only for emulation use, not writing back to real disks?

Good question, with a complex answer. In short, the IPFs are for emulation only. The diamond-shaped flux pattern for which the DM protection is infamous cannot be represented in an IPF. Instead the generated IPF uses very short (1-2 bitcell) weak regions to simulate the fuzzy most-significant bit in each data byte in the protection sector. Not a problem for an emulator to randomise one or two bits; but impossible to write to disk without being smart enough to swap back in something like the "diamond flux" trick.

To write to disk, the IPF can be converted to SCP using disk-utilities. The generated SCP *does* have the diamond-shaped flux pattern and will write to disk just fine using, for example, Greaseweazle.

Finally, I am working on IPF to HFEv3 conversion in the Greaseweazle tools. This will also support conversion of the DM and CSB IPF images to HFEv3 images which FlashFloppy will support. However it will require a small extension to HFEv3 to support bit-granularity weak regions. So will require a new release of both Greaseweazle tools and FlashFloppy firmware. Watch this space in the coming weeks.

EDIT: It might be worth zipping the IPFs up with a README which summarises the above, if uploaded to the server.

[Retroplay]

I uploaded Barry's ipfs to my user upload folder all renamed TOSEC style with a readme quoting what Keir wrote above.

The diamond-shaped flux pattern for which the DM protection is infamous cannot be represented in an IPF.
Instead the generated IPF instead uses very short (1-2 bitcell) weak regions to simulate the fuzzy most-significant bit in each data byte in the protection sector.
Not a problem for an emulator to randomise one or two bits; but impossible to write to disk without being smart enough to swap back in something like the "diamond flux" trick.

@TCD
I upped three ipfs yesterday, these will be supported in disk-analyse once Abaddon pushes his update to disk-utilities git repo.

All tested and verified working 100%.

[BarryB]

I did wonder if SCP was still viable for writing, you've now explained it is

HFEv3 files aren't that much bigger than IPF, probably 2mb over 1mb, but with large GB capacity USB sticks going for a few quid that won't be an issue!

[Keir]

Originally Posted by BarryB

I did wonder if SCP was still viable for writing, you've now explained it is

HFEv3 files aren't that much bigger than IPF, probably 2mb over 1mb, but with large GB capacity USB sticks going for a few quid that won't be an issue!

I was intending to add native IPF support to FlashFloppy for the newest Goteks with more RAM and CPU power. However I realised that supporting conversion to HFEv3 is good enough, and a lot easier!

[BarryB]

Originally Posted by Keir

I was intending to add native IPF support to FlashFloppy for the newest Goteks with more RAM and CPU power. However I realised that supporting conversion to HFEv3 is good enough, and a lot easier!

And it will make it compatible with ALL Goteks!!

[Supamax]

Originally Posted by Keir

I was intending to add native IPF support to FlashFloppy for the newest Goteks with more RAM and CPU power. [...]

Are there new Goteks with more RAM an processing power?
Where? An example link?

[TCD]

Originally Posted by Retroplay

@TCD
I upped three ipfs yesterday, these will be supported in disk-analyse once Abaddon pushes his update to disk-utilities git repo.

All tested and verified working 100%.

Thank you for confirming I've moved the four new unofficial IPFs over to 'Non TOSEC IPFs - Unofficial'.

[Keir]

Originally Posted by BarryB

And it will make it compatible with ALL Goteks!!

Yes indeed!

[Keir]

Originally Posted by Supamax

Are there new Goteks with more RAM an processing power?
Where? An example link?

Description and comparison with older MCUs:
https://github.com/keirf/FlashFloppy...rtery-at32f435

Not so easy to find still, unfortunately. I have an eBay page (UK sales only):
https://www.ebay.co.uk/itm/125672833445

There are other sellers internationally. The quickest way to get these more generally stocked is to ask for them by name. From the factory a Gotek with the new MCU costs no more than a dollar more. It should be a no brainer for new FlashFloppy (and HxC) installations.