35 replies to this topic

[birdie3]

I am using a 1050. Can anyone recommend a good DOS. Nothing freaky - OK?

[Almost Rice]

ijor, on Thu Jan 5, 2006 11:56 PM, said:

The reason for this was in first place, that it is much simpler to produce the bottom head than the top one that it’s “floating”. And when DS drives were designed, the goal was to maintain backwards compatibility with SS drives.

That makes sense.

[highendsystems]

I agree with everyone about the HD floppys not working right with Atari drives.

My uncle gave me a box of HD diskettes, but I quit messing with them because
the data got corrupted. I do however have 1 that is full of games, and has
never given me any problems. Why that 1 I dunno....

[Bryan]

Yes, you need to avoid HD disks.

By the way, the problem with making flippies in an XF551 is due to the index hole that goes missing when you flip the disc. The XF551 uses it when formatting and the 1050 does not (actually the controller always requires it to format, but the 1050 fakes the pulse instead of having an actual sensor).

The XF551 can write to the back side of a disc formatted on another drive, though.

-Bry

[MEtalGuy66]

Bryan, on Mon Mar 13, 2006 4:56 PM, said:

Yes, you need to avoid HD disks.

By the way, the problem with making flippies in an XF551 is due to the index hole that goes missing when you flip the disc. The XF551 uses it when formatting and the 1050 does not (actually the controller always requires it to format, but the 1050 fakes the pulse instead of having an actual sensor).

The XF551 can write to the back side of a disc formatted on another drive, though.

-Bry

YEP.. I was waiting for someone to say that. You are correct about the index hole.. And.. Most of teh "upgrade" roms for the XF551 eg. XF551 enhancer, HyperXF, etc. FIX this problem. Im not sure what manner of a fix it is, you may have to do something on the command level when accessing/formatting these "flip sides" but both my XF551s are bone-stock, and I don't plan to modify them. Ive got plenty of boxes of brand new DSDD disks still in the shrink-wrap, so I just use full 360k floppies for DOS disks, and single sided for raw sector/track-loading disks.

[ijor]

MEtalGuy66, on Mon Mar 13, 2006 6:50 PM, said:

You are correct about the index hole.. And.. Most of teh "upgrade" roms for the XF551 eg. XF551 enhancer, HyperXF, etc. FIX this problem. Im not sure what manner of a fix it is, you may have to do something on the command level when accessing/formatting

Hmm, no ROM upgrade could fix this. As Bryan explained it's a limitation of the controller. The FDC won't start the format it it doesn't see the index pulse. There are some fixes, but they involve more than just ROM change.

Also, not every XF-551 can read and write to the flippy side. It depends on the mechanism. Some mechanism don't become ready if they don't see the index hole (disregarding the FDC issue). It seems that most units sold in US don't have this problem. I think that the FAQ mentions which brand mechanisms can access the flippy side and which not.

It is possible that this could be fixed messing with the drive's jumper. Some have jumpers to select the condition to become ready. But this is only for being able to read or write to the flippy side. Formatting is still limited by the FDC.

[Artlover]

Yeah, HD disks are nearly useless for anything less then a HD compatable drive. This is true in CBM land too. The magnetic properties of the oxide layer is different.

Another issue is a lot of HD disks tend to be PC pre-formated. This in itself creates problems of interference when reformating at SD/DD as you'll end up of traces of the original HD tracks remaining between the tracks of the new format that can cause the any r/w operation, even the format itself, to fail. Tho bulk erasers can eliminate this particular problem.

Also, should be noted, disk density seems to effect 5.25" disks more then 3.5" ones. While I could never get any 5.25" HD disks to work with my C1541, C1571, A810 or A1050's, most of the 3.5" HD disks I used with my 1581 did work. Notice that I did say "most", as not all did.

Was there ever a 3.5" floppy drive for the Atari 8-bit line? My searching only comes up with the SF-314 which is an ST drive.

[jaybird3rd]

Artlover, on Mon Mar 13, 2006 8:58 PM, said:

Yeah, HD disks are nearly useless for anything less then a HD compatable drive. This is true in CBM land too. The magnetic properties of the oxide layer is different.

Another issue is a lot of HD disks tend to be PC pre-formated. This in itself creates problems of interference when reformating at SD/DD as you'll end up of traces of the original HD tracks remaining between the tracks of the new format that can cause the any r/w operation, even the format itself, to fail. Tho bulk erasers can eliminate this particular problem.

Also, should be noted, disk density seems to effect 5.25" disks more then 3.5" ones. While I could never get any 5.25" HD disks to work with my C1541, C1571, A810 or A1050's, most of the 3.5" HD disks I used with my 1581 did work. Notice that I did say "most", as not all did.

Was there ever a 3.5" floppy drive for the Atari 8-bit line? My searching only comes up with the SF-314 which is an ST drive.

There was never a 3.5-inch drive released for the A8 series. Curt has a few pictures on his website of the prototype XF-351 3.5-inch drive, which was apparently finished but never released. However, as everyone probably already knows, it's merely a matter of swapping out the drive mech and upgrading the ROM to make the XF-551 into a 3.5-inch drive. I originally used Bob Woolley's upgrade for this, which patched Atari's original ROM and in effect made the drive into an XF-351, but the Hyper-XF upgrade is a major step up so I'm now using it instead.

The density issue is interesting: I've got a lot of HD 5.25-inch disks and haven't had any luck with them in any of my Atari drives. As you say, the properties of the media are too different, and using a HD drive with the XF-551 doesn't work either (I've tried). 3.5 inch disks, whether DD or HD, will format just fine to 720K; it sometimes takes one or two extra formats for the HD disks but they're perfectly reliable after that. The only trouble you might encounter with HD media is if you happen to have a 1.44MB mech in your XF-551: it will switch to HD mode if it detects the second open window on the diskette and won't work in the XF-551 if that happens. You can cover the window on every disk, but I found it a lot easier to simply wire the switch closed permanently in my drive. This shouldn't be an issue with true 720K mechs, though.

[MEtalGuy66]

ijor, on Mon Mar 13, 2006 6:00 PM, said:

MEtalGuy66, on Mon Mar 13, 2006 6:50 PM, said:

You are correct about the index hole.. And.. Most of teh "upgrade" roms for the XF551 eg. XF551 enhancer, HyperXF, etc. FIX this problem. Im not sure what manner of a fix it is, you may have to do something on the command level when accessing/formatting

Hmm, no ROM upgrade could fix this. As Bryan explained it's a limitation of the controller. The FDC won't start the format it it doesn't see the index pulse. There are some fixes, but they involve more than just ROM change.

Also, not every XF-551 can read and write to the flippy side. It depends on the mechanism. Some mechanism don't become ready if they don't see the index hole (disregarding the FDC issue). It seems that most units sold in US don't have this problem. I think that the FAQ mentions which brand mechanisms can access the flippy side and which not.

It is possible that this could be fixed messing with the drive's jumper. Some have jumpers to select the condition to become ready. But this is only for being able to read or write to the flippy side. Formatting is still limited by the FDC.

Well, I believe it did come with a ROM. heres the link:
http://www.nleaudio....ts/XF551enh.htm

[warerat]

MEtalGuy66, on Tue Mar 14, 2006 8:22 PM, said:

ijor, on Mon Mar 13, 2006 6:00 PM, said:

MEtalGuy66, on Mon Mar 13, 2006 6:50 PM, said:

You are correct about the index hole.. And.. Most of teh "upgrade" roms for the XF551 eg. XF551 enhancer, HyperXF, etc. FIX this problem. Im not sure what manner of a fix it is, you may have to do something on the command level when accessing/formatting

Hmm, no ROM upgrade could fix this. As Bryan explained it's a limitation of the controller. The FDC won't start the format it it doesn't see the index pulse. There are some fixes, but they involve more than just ROM change.

Also, not every XF-551 can read and write to the flippy side. It depends on the mechanism. Some mechanism don't become ready if they don't see the index hole (disregarding the FDC issue). It seems that most units sold in US don't have this problem. I think that the FAQ mentions which brand mechanisms can access the flippy side and which not.

It is possible that this could be fixed messing with the drive's jumper. Some have jumpers to select the condition to become ready. But this is only for being able to read or write to the flippy side. Formatting is still limited by the FDC.

Well, I believe it did come with a ROM. heres the link:
http://www.nleaudio....ts/XF551enh.htm

I've got some XF551's with Enhancers. It's a potted module with a bunch of wires soldered to the mainboard. The XF551 I have has a CSS ROM for 3.5" floppies and Ultraspeed.

[ijor]

MEtalGuy66, on Tue Mar 14, 2006 3:22 PM, said:

ijor, on Mon Mar 13, 2006 6:00 PM, said:

MEtalGuy66, on Mon Mar 13, 2006 6:50 PM, said:

You are correct about the index hole.. And.. Most of teh "upgrade" roms for the XF551 eg. XF551 enhancer, HyperXF, etc. FIX this problem. Im not sure what manner of a fix it is, you may have to do something on the command level when accessing/formatting

Hmm, no ROM upgrade could fix this. As Bryan explained it's a limitation of the controller. The FDC won't start the format it it doesn't see the index pulse. There are some fixes, but they involve more than just ROM change.

Well, I believe it did come with a ROM. heres the link:
http://www.nleaudio....ts/XF551enh.htm

Of course that it came with a ROM. But it was a hardware upgrade than involved much more than just a ROM.

So may be I misunderstood you, or you misunderstood me. My point is that you need a hardware modification, and that it couldn't be fixed just with a new ROM.