Modifying PC floppy drives for Amiga use

[laser]

Originally Posted by narmi

It cannot be done, since the ready signal is not present on the 34-pin connector of a PC drive. Some drives (those posted in this thread) have a ready signal available on their PCB which can be routed to the correct pin on the 34-pin connector.

I understand now...so to make any pc drive works on the amiga this steps should be made:

1-set the drive to unit 0 using a jumper or link

2-route diskchange to pin 2

3-search ready signal on the drive and route to pin 34

is that correct?

[a_petri]

Originally Posted by Chain

We have same thread on czech amiga portal.
If anybody needs translation of some hack just ask.
They are all tested and works.

http://amiga.probers.info/forum/forumdisplay.php?f=129

Did I understand correctly that you have discovered another PC 1.44M floppy drive (the one shown in the "Alps Electric, alebo mrcha HDcka" thread) which can be modified as a *HD* Amiga floppy???

[Jope]

Originally Posted by laser

1-set the drive to unit 0 using a jumper or link
2-route diskchange to pin 2
3-search ready signal on the drive and route to pin 34

is that correct?

That's correct.

[laser]

thanks Jope

I have another question :

on the pc the "density select" is on pin 2..but if you route diskchange to pin 2...that function will be destroyed so no High density disk can be recognized on workbench (I think)

I know that the commodore A4000T comes with a high density drive.....so which pin is "density select" on the A4000T motherboard?

anyone have pinout of the A4000T internal floppy connector?..I can't find that info on the web

[gizmomelb]

has anyone ever managed to convert a PC HD floppy so it works with the Amiga?

Wouldn't an extra 'slowdown' circuit need to be added to the PC drive?

[Jope]

Originally Posted by laser

I know that the commodore A4000T comes with a high density drive.....so which pin is "density select" on the A4000T motherboard?

This is detected by trackdisk.device using the ready bit stream.

http://aminet.net/package/docs/hard/PCFloppy2Amiga has info on the ready pulses and other Amiga disk related issues.

anyone have pinout of the A4000T internal floppy connector?..I can't find that info on the web

http://www.wonkity.com/~wblock/a4000hard/inflpins.html

Originally Posted by gizmomelb

has anyone ever managed to convert a PC HD floppy so it works with the Amiga?

Wouldn't an extra 'slowdown' circuit need to be added to the PC drive?

I haven't heard of anyone doing it successfully. Reports have been that the drive doesn't spin reliably at 150rpm..

[gizmomelb]

thanks Jope! I'll get on with some reading.

Ok, Amiga semi-newb here at your service. I had an A2000 back in the day, but had a fire at the house and it got auctioned off for peanuts. Now years later, I decided I'de like to collect all the old games and stuff I had.. so I picked up an A3000 on Ebay for a bit over $200 US.

Problem... I can't seem to get anything running properly. Hero's of the Lance just gives me a read disk error screen. Some others kind of work, then die.

Champions of Krynn would load up using the floppy drive to boot up, but during the demo would freeze while loading a certain part.

Hillsfar makes it look like its going to load, but then just goes to a blank screen.

Starflight again, almost works, but when I go to start a new game I get disk write errors.

Ok, so I figured, maybe I have a floppy drive issue... all these A500 A1000 A2000 games should work on the 3000 right? (I couldn't get a straight answer on that one from anyone I asked).

So I bought an FZ-357 on ebay after seeing some spreadsheet somewhere that said it would work on an Amiga with no modifications.

Get the drive, install it, it doesn't work.. maybe I flipped the cable... still doesn't work. Ok , so now I find another site that says you have to take the drive apart solder the J2 jumper and set external jumpers... ok... so I manage to get all that done with some help. (Far from "no modifications").

I have high hopes... put in Champions of Krynn.. it looks like its going to work. Select to start the demo, it asks for disk 3, I insert disk 3 and nothing...nada..nil... Retry...retry...retry... nope... Its not even trying to read the disk.

Alright, well let me try the Heroes of the Lance. Nope, still get the red guru like disk error when trying to load that one. (Do I remember something about those silver box games all being PAL by accident? I dont rememeber, back in the day, I needed the guy from Electronic Boutique to make me some special PAL loader disk though to play that one, I thought maybe I accidentily bought a PAL version back then.. but maybe not?)

Any ideas what my problem is here?

Could it be 2 bad floppy drives?

A500, A1000, A2000 games not compatible with A3000?
Something bad in the machine itself somewhere?
I did try cleaning the original drive with a drive head cleaner disk and giving it a good squirt of compressed air. It didn't help.
If you think its a floppy drive issue, can I get one of these that your talking about in this thread?

Thank you for reading, I appreciate any assistance.

Originally Posted by narmi

As promised, more eye candy! The label below is from the first drive I modified. The second one has the same model number, but is a REV.T1 part. The PCB inside both drives is virtually identical.

Nice! I have the same drive in my PC. Can i use it my A500 if I do those modifications? Can i read/write HD-drives when i replace the drive?
EDIT: I discovered that the drive is to low. I can make some spacers and make the drive higher. The eject button is to centered but with some modifications to the plastic shell of the A500 solves that problem.

[narmi]

I use mine in my A500 to avoid wear and tear on the original drive. Try it and let us know!

Originally Posted by narmi

I use mine in my A500 to avoid wear and tear on the original drive. Try it and let us know!

Can you format HD discs with it or is it a limitation of the fdd controller?

[Jope]

You can format HD disks as DD.. Use a piece of tape over the HD cover hole. Naturally you don't get HD capacity or much reliability, but it is possible to use HD disks this way.

The floppy controller indeed can't keep up with the PC drive's HD datarate and also the PC drive does not supply the right identification pulse for the OS to know that the floppy you inserted is HD.. Thus the drives will work as DD only in Amiga use.

[Jope]

Originally Posted by rcosner

Ok, so I figured, maybe I have a floppy drive issue... all these A500 A1000 A2000 games should work on the 3000 right? (I couldn't get a straight answer on that one from anyone I asked).

No-one can remember the compatibility of all games.. :-)

Check http://hol.abime.net/ .. Even that doesn't have up to date info on everything.

I suggest you try and find a plain A500 to test the games on if you suspect bad disks.

So I bought an FZ-357 on ebay after seeing some spreadsheet somewhere that said it would work on an Amiga with no modifications.

This would be the FZ-357A .. The FZ-357 (without the trailing A) is the PC version which will need modifications..

Get the drive, install it, it doesn't work.. maybe I flipped the cable... still doesn't work. Ok , so now I find another site that says you have to take the drive apart solder the J2 jumper and set external jumpers... ok... so I manage to get all that done with some help. (Far from "no modifications").

..as you soon found out.

Any ideas what my problem is here?

Could it be 2 bad floppy drives?

It could..

A500, A1000, A2000 games not compatible with A3000?

Quite probable. The A3000 has a faster CPU with caches that will break many games.. Also kickstart 2.04 is a problem for some older titles.

Something bad in the machine itself somewhere?

Based on your explanation, it's most likely just the fact your games aren't A3000 compatible..

If you think its a floppy drive issue, can I get one of these that your talking about in this thread?

Sure.. Contact me if interested. However I'd try to get the games working on a plain 68000 machine first to see whether the media is broken.

Try and get confirmation on the drives working by using a regular DOS disk first, such as Workbench.

Can you boot up Workbench from floppy? Can you successfully copy your Workbench disk to an empty floppy with the drives you currently have?

Then once you know that the drive reads / writes properly, you might want to try relokick and/or degrader to turn off advanced features of the A3000 to help the games run. I think you should start testing with some other drive than the FZ-357 you mentioned, just in case the modifications didn't work.

[DrF]

I would love a HD drive just for err having it, I guess, I am hoping to order the CatWeasel this week, has anyone got any experiance with this device and various drives?

[Jope]

The Catweasel is pretty compatible, only a couple of models that don't work with it. Naturally you can not boot off HD disks even if you use a Kylwalda.

The Catweasel requires PC floppy drives, you mustn't modify them for Catweasel use.

Originally Posted by Jope

This is detected by trackdisk.device using the ready bit stream.

I haven't heard of anyone doing it successfully. Reports have been that the drive doesn't spin reliably at 150rpm..

Some guys on a1k did it.
http://www.a1k.org/forum/index.php?m...d=2&thread=572

I am one of the beta-testers and i made a testrun-movie.
http://www.a1k.org/download/area51/HDFloppyFix.mpg

Its a TEAC FD-235HF drive.
1760kb / 1440kb ofs/ffs/fat - read/write
880kb / 720 kb ofs/ffs/fat - read/write

First we had some problems with timings from the diskready-signal (hd-mode) in combination with an a1000.

[Jope]

Great news. I have a new project for you, please try and modify the JU-257A606P, as TEAC drives are very far in between around here. ;-)

When I have the energy, I'll read through that thread and try to understand what everyone's saying.

For some news (final revision) visit this page:
http://www.a1k.org/forum/index.php?m...ost_nr=680#680

Originally Posted by Ratte

For some news (final revision) visit this page:
http://www.a1k.org/forum/index.php?m...ost_nr=680#680

That looks like a thing worth building :-)

[Jope]

Can you give us a quick rundown? Does it require modifications to the drive in order to work, or is it some kind of track cache that reads the track and then feeds it half speed to the Amiga?