Floppy drive write error - using pc 1.44 modified

[Telsud]

Hi everybody,
I tried to modify many old pc floppy drives to make it work on my ST.
Most of them are easy to convert (jumper or solder DS1 to DS0 ) and that's all (seems to have less things to do than Amiga drives, with RDY signal and disc change). But I also tried experiments with it too.
These drives properly works exept when formatting or copying 10 sector floppy with FCOPY III. When writing, about in the middle , on track 40-50, the drive stops to do noise and become inactive. But the writing go to the end without errors. Of course the disc does not work.
When using FCOPY PRO with soft format mode, it works.
Can you explain me why this happens? These drives are not totally compatible with the Atari or there is something more to do?
Thanks for tour help.

[exxos]

Tried other floppies ? Are you formatting with 9 sectors 79 tracks ? Not changed any default options in fcopy ? Do any drives work correctly ?

[Telsud]

Hello Exxos, thanks for your answer.

Same settings since 33 years :mrgreen:

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Works with 9 sector disks, does not work with 10 sector disks.
This Time it begans on writing track 46.
Tried both dd and HD disks
Tried mitsumi teac Sony drive and many others.
I will try old Atari drive to check if the Atari itself have a problem... (Non modified 1040 stf).

[exxos]

Works with 9 sector disks, does not work with 10 sector disks.

You mean the format completes fine with 9 sector formatting but not 10 sector formatting ?

This Time it begins on writing track 46.

What begins on track 46 ? The actual start of the format ? Or something else ?

[Telsud]

Yes, the copy process works with 9 sector format but fails when using 10 sector.
That happens when writing the destination. All begins fine, but when reaching the track 46, no more sound, the drive seems to be idle. On screen, the copy keep on going to the end.
Stange don t you think?

[exxos]

Yes, the copy process works with 9 sector format but fails when using 10 sector.

This would suggest either the floppy itself for the floppy drive is not capable of extended formats.

That happens when writing the destination. All begins fine, but when reaching the track 46, no more sound, the drive seems to be idle. On screen, the copy keep on going to the end.
Strange don't you think?

I would look at your drive head physically and see if it resets to tracks zero at the start of the format.

The only time I have seen a drive fall silent during a format, Is when trying to format too many tracks, the drive hits physical end limit of the head movement, then will fall silent because they simply cannot move to format the additional tracks. Though normally this starts around track 80. It depends on the drive itself because some drives can support extended tract but not others.

The same symptom can be present if the drive is not resetting to tracks zero correctly. The drive may be starting at track 40, the floppy drive head may be physically at track 86 at that time. Almost no drives support that format.

[Telsud]

Very intersting... let s try some experiments...

I think the floppy IS capable because it works well when using FCOPY PRO soft format mode with pc drive and (I tried!) when using old Atari st drive.

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For the second assumption I think you re right, but how test it?
As the destination disk cannot boot after copying that means track 0 is not good, so the error is from the beginning !
It means the drive send the wrong signal and/or FCOPY III do not check it properly?
Or the drive conversion I ve done is not correct, (ds1 to ds0 only), and something else should be done ?

[exxos]

I don't know what the soft format option does, it may just write the FAT and do nothing else. That could literally end up anywhere on the disc.

You need to take the top of the floppy drive and see exactly what the heads are doing. When you turn on the ST he should reset back to track 0. I think this is towards the outer of the disc.

On some drives you can manually manipulate the motor shaft and move the heads towards the centre of the drive and make sure you fully track back to the edge of the disc on power up.

[PhilC]

Just a quick suggestion. Tape over the HD detect hole. On one of my drives it wouldn't format to 720K without doing that.

[Telsud]

Ok thank you Exxos, I will do some experiments.
Do you confirm that the only I must do to convert correctly a drive IS toi change ds1 to ds0?

Thank you too Phil, but already done ;)

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