"XF351" (from Zaxon) users thread

[LessNick]

12 hours ago, Larry said:

It should be able to read a disk that it has just written.  But mine won't do that reliably, at least in DD .

There is a very high probability that the problem is not in the device itself, but in the floppy disks.

If these are modern replicas of floppy disks from China, there is a high probability that they have a very weak magnetic layer and therefore unstable recording.

If, on the contrary, these are old floppy disks, then their magnetic layer may also degrade over time.

 

In any case, before using them, it is worth pre-formatting them several times.

 

Unfortunately, on Atari drives there is no way to control the formatting process itself, only to get the final result, whether it was successful or not.

 

That's why I pre-formatted the diskettes on the ZX Spectrum, where you can really see how the process takes place: formatting, recording, checking.

If there are no problems with the diskette and there are no bad sectors, you can say with confidence that the diskette will be formatted on the atari without any problems.

[LessNick]

7 hours ago, kheller2 said:

Zaxon's other boards are overclocked just like the XF551. So this shouldn't be THE problem.

It's strange to hear this, of course. It seemed to me that he simply repeated the original XF351 scheme? No?

At least I didn't see any modern components like altera.

 

It might be a matter of quartz, but I haven't disassembled my drive yet and can't say what frequency it has.

[+Larry]

Yes, my DS/DD disks are old.  Even NOS.  But oxide issues wouldn't explain why my Hyper 3.5 has zero trouble with these disks.  To me this points to the mech, but we'll see.

 

@kheller2  Good to know about the clocking and SCOPY -- thanks!

 

Today, I'm going to take a step back, and test in single density.  This drive reminds me of the early days when I got my first Rana (~1984).  It would not do DD -- It could write out a disk in DD just fine, but then it could not read back the same disk.  Sent it back and got a replacement -- did the same thing. (sigh!)  Later Ranas were definitely better.  But with the help of Paul Alhart, I put a 1050 Tandon mech in the Rana, and that fix definitely was the best.

 

[+Larry]

My plans for testing in Single Density were thwarted -- the drive appears to be DD only.  Could someone check that on theirs?

 

Also, to continue testing, I broke out a box of new Maxell 2DD disks.  I'm just about to the end of these new disks, maybe down to the last few boxes.  However, when I bought them, they were a steal -- check the pics.

[+Larry]

Well, I think I'm finished with my testing.  I definitely had better luck using the brand new disks.  But then I also used a bulk eraser on some old disks and had equal success.  I used Hias' HISIO.COM driver, and it worked as well as the SDX driver for the XF351.  With Hias' driver I can use all my MyDos copiers and other things I'm familiar with.  But using the SDX formatter is definitely the way to go.  It's not a big deal to me that the drive apparently does not support single density. It does support single side and double side use.  Sometime in the future I'll take the guts out and see about putting in a 1772 and using the Hyper+ XF rom. 

 

Would I recommend this to others?  Not as your only drive, but if you have other Atari or 3rd party drives, why not!  About $150 U.S. including shipping, so I think it is worth it for a nice drive that doesn't take up much space.

[+kheller2]

Silly question but what ROM is in there now?

[+Larry]

Not silly at all.  It's (I think) a modified XF551 rom.  It will do regular SIO speed and 2X High Speed.  Regular DD SIO on a 720K disk is brutally slow.  This is somewhat better.  Ultra Speed is my goal.  An issue is that the mech. is held in place with a plastic tab that appears to be Super Glued to the case.  But sooner or later it's got to go -- if nothing else I want a good look at that mechanism.

 

Edit: One more tidbit about the mech.  I still have several original DD and HD 3.5" mechs from the 90's.  My smallest 3.5" mech. is still about 3/16" wider and nearly 1/2" longer than the mech. that is in the XF351.  And there is too little clearance even my smallest old-style internal 3.5' to fit in the XF351 case.

[+kheller2]

It is unusual that you can't read your old 720 disks in your new 1.44 thin line mech.

Unless something is seriously out of alignment with the old 720...  or there really is something fundamentally wrong with the 1.44. 

 

I fully expect that formatting USED media on the 1.44 (as 720) and using it in the 720 drive would fail.

Virgin unformatted media might behave differently.

 

Besides the difference in track width, you get into the whole issue of floppy coercivity. 

Your previously formatted 720K disks in the 720 Drive... were not HD disks were they?

 

[Peri Noid]

My suggestion is... Get a Greaseweazle somewhere and dump one of your old disks to an SCP file. Then open it with HxC Floppy Emulator software and have a look at how the sectors are located and how the disk was actually formatted. Otherwise you know nothing. 

Edited July 29 by Peri Noid