PC to Oric 3.5" floppy

[iss]

By me cleaning the drive heads helped lot. Rotation speed is important too....
EDIT: attaches is BASIC source and DSK of an 'INDICATEUR DE VITESSE DE LECTEUR'

Code: Select all

 100 REM ###########################  
 105 REM
 110 REM INDICATEUR DE VITESSE DE LECTEUR
 115 REM
 120 REM ###########################
 130 REM
 
 140 HIMEM#0FFF:POKE#BB80,#17:POKE#BB81,0
 
 150 A=#1000:REPEAT:READV$:V=VAL("#"+V$)
 152 POKEA,V:A=A+1:UNTILV=#60
 160 POKE#26A,14:CLS:PRINT
 170 PRINT"CHOISIR LE LECTEUR ET TAPER ESPACE"
 180 DOKE#BB90,#4241:DOKE#BB92,#4443
 190 KEYIF#AETHENPOKE#BB90,#C1:L=#86:GOTO250
 200 KEYIF#92THENPOKE#BB91,#C2:L=#A6:GOTO250  
 210 KEYIF#BATHENPOKE#BB92,#C3:L=#C6:GOTO250 
 220 KEYIF#B9THENPOKE#BB93,#C4:L=#E6:GOTO250 
 230 KEYIF#A9THENEND
 240 GOTO180
 250 KEYIF#84THEN280
 260 KEYIF#A9THENPOKE#26A,15:END 
 270 GOTO 250
 280 CLS
 290 PLOT2,4,"AUTRE TEST : ESPACE"
 300 PLOT2,6,"SORTIR     : ESC"
 310 POKE#1002,L:POKE#4FB,L
 320 CALL#1000
 325 V$=STR$(60E6/(DEEK(0)*13+PEEK(1)*4))+"  T/mn"
 330 PLOT2,2,"VITESSE     :"+V$
 340 KEYIF#84THEN170
 350 KEYIF#A9THEN POKE#26A,15:END
 360 GOTO 320
 370 DATA78,A9,86,8D,14,03,A9,08,8D,10,03,AD   
 375 DATA10,03,29,02,F0,F9,AD,10,03,29,02,D0
 380 DATAF9,A2,00,A0,00,AD,10,03,29,02,D0,06
 385 DATAE8,D0,F6,C8,D0,F3,AD,10,03,29,02,F0
 390 DATA06,E8,D0,F6,C8,D0,F3,86,00,84,01,58
 395 DATA60

I don't know from where I've got this, my is only line 140 to make it functional in Oricutron,
but it seems to hang in emulator.
It's for microdisc and I don't know if it works at all

vitesslec.zip

(31.5 KiB) Downloaded 557 times

[Symoon]

Hey thanks.
Yesterday I almost fried another PC trying to use a 3" drive on it, and this morning my old Microdisc (master) for a real Oric doesn't seem to work anymore.

I think I'm cursed with disks

[Symoon]

Using (finally!) Silicebit's controller and a 3" drive, I tested 7 more disks: all are faulty.
Some make a terrible rotation sound.

ISS, you said you cleaned drive heads, how are you doing this?

[iss]

I tried to make some photos of cleaning but the result is ugly and nothing important can be seen.
I will try next days to repeat the process but this time with helper (two hands are not enough for the task).
BTW, here is a good clip for cleaning 3.5" PC floppy:
... and on youtube can be found more nice clips.

In general this is the procedure. Just be careful with 2 things:
- do not lift the upper head to high;
- be very very gentle with the upper head by cleaning because it is not hard fixed but moves.

EDIT: for cleaning I'm using ethyl (medical) alcohol 70 or 90%.

[Chema]

You know there is an elastic band inside those drives, do you? With time, this band loses its properties and drives stop working properly.

You can buy a new one and change it. That is one of the first things that people do to repair old 3" drives.

Some retro shops still sell those belts. They had them here https://www.micomputer.es/es/oric/8-gom ... &results=8 but it says they are out of stock now. You can ask, I know the guy and he is trustworthy and helpful.

There are many tutorials about the procedure (mostly for Amstrad CPC) such as this It seems to be easy enough, but for a small bolt that usually falls out of its place if you do not proceed with a disk inserted in the unit.

But I never actually did this...

[Symoon]

Thanks for the replies guys.
I think I've read somewhere that Oric and Amstrad drives were different, and the belt couldn't be changed on Oric drives? But that's very old memory.
BTW the drive did read fine a Sedoric disk I made a couple of years ago, so I think it's running fine. Head cleaning was just a "last idea before giving up".

Now I wonder if specific disk reading cards like Kryoflux could be of any help. It's heavily used in Atari ST world, I should ask a friend.

[iss]

In my opinion the Kryoflux is very good (maybe even the best) option for recovery unreadable disks.
It's absolutely worth to try especially when you have a friend who owns one. Else it's bit expensive (100 or 130 EUR) for me.
I have working prototype based on arduino which dumps track-by-track bit-streams from disks but the software for analyze is in very early stage far from ready...

[Symoon]

Apparently, there are two specific cards available: Kryoflux or Supercard Pro.
What I still fail to understand with Kryoflux, is the way low-level files work. Seems they have a "stream file" format, and "IPF". I suspect "stream file" is the reading of the disk "as is" (a would be a WAV file for a tape), and can't be analysed by the user?
They gather it from the user and build an IPF file from it... Well I'm not sure but I think it's the way it works? I recall I made stream files for them on my Amiga about 15 years ago, and they didn't send me back IPF files for all of them.

If that's still the way it works, not being able to analyse yourself the content of the raw reading is a serious drawback (though I'm not sure I would ever be able to analyse anything from a disk raw read!). But still, I may be completely wrong in the way they are working.

[iss]

Yes, the way it works is just like the recorded WAV for tape, but higher frequency is used and the values are only 0 and 1.
After recording some algorithms are used to detect logical fields in the track structure. Of course 100% success can't be guaranteed.

[Symoon]

That's exactly like the Oric tape tools
My concern is: if we depend from over-busy people at the other end of the planet for the decoding, I don't see why they would waste their time on decoding personal disks.
I understand they want to preserve original software - and control the dumps people are doing, which I plainly understand. But it makes it inefficient for us, when just trying to recover private work disks.

[tingo]

This might be an interesting project: FluxEngine. Currently it only supports standard IBM PC format and a Brother Word Processor format, but the project is open source and the hardware is quite cheap.

Downsides (for me at least): the necessary development tool - Cypress' PSoC Creator - runs only on Windows, I haven't manged to get it running in Wine so far.

[romualdl]

@Symoon : discussion here in french about the 2 different solutions (Kryoflux and Supercard pro) showing the limits and advantages of those 2 solutions : https://forum.system-cfg.com/viewtopic.php?f=6&t=8555

[Symoon]

Quite interesting, thanks Romu.
Seems almost nobody tried them with 3" drives yet, I read somewhere that only some tests were made with a few Amstrad drives. So the card builder was only certifying the card to work with one 3" drive model.

[NekoNoNiaow]

In my opinion the Kryoflux is very good (maybe even the best) option for recovery unreadable disks.
It's absolutely worth to try especially when you have a friend who owns one. Else it's bit expensive (100 or 130 EUR) for me.
I have working prototype based on arduino which dumps track-by-track bit-streams from disks but the software for analyze is in very early stage far from ready...

The Kryoflux has some limitations though in that it has trouble recognizing special protections such as the ones used on the Apple II where disk data was written in a spiral like pattern. This is why the Apple enthusiasts have created the Applesauce hardware and software package as well as the WOZ disk format which allows to properly encode all these weird non conventional ways of writing data to a disk. (There are details about all that on the site I linked to.)

I do not know if the AppleSauce hardware/software supports 3" disks but if there are complex protections on Oric disks, it might be worth giving a look since the Kryoflux might not be able to handle them.

[Steve M]

I used to get problems with the DIP switches on 3" drives. The second bank used to have an effect although people stated it shouldn't.
Be careful to power off before changing settings. I've killed a few drives swapping connections or flicking switches when I thought the power was off.