How to get two external drives to work with 520STM?

[bfollowell]

OK, I'm checking out my ST drives and trying to confirm read/write operation. I have three external drives; two SF314s and a Golden Image 3A-1D. I have two drive cables. Using them singly, I've verified both cables seem good and all three drives read and will boot the system. However, whenever I try to connect two drives, I can never seem to get the second one recognized. I have the drive cable going from the back of the ST to the in port on drive A, and the second drive cable going from drive A's out port to drive B's in port. It seems pretty straight forward and I don't think I'm doing anything wrong, but I can't seem to get the system to recognize that I have two drives.

I have Floppy A and Floppy B icons on the desktop whether I have one drive or two drives hooked up. When I boot, double-clicking on Floppy A will show me whatever is in Drive A. Double-clicking on Floppy B brings up a dialog box that says Please insert disk B into drive A. It does this, again, with one or two drives connected.

I've only found one site that seemed to mention connecting two drives to an ST, and it said that everything needed to work with two drives is built into the system. Someone else told me that I need to somehow mount the second floppy icon as a real drive rather than being used with drive A for disk swapping. I haven't been able to find anything online about how to do that.

I should mention that this is a 520STM with original TOS 1.0 and no internal drive.

Am I doing something wrong or is there something wrong with my system?

Thanks.

[stephen_usher]

Plugging in my SF314 and a no-name external drive into that has always worked without a hitch. You just have to make sure you have the "IN" and "OUT" cables going to the correct places. (i.e. "IN" on the SF314 comes from the STM and "OUT" goes to the second drive.)

e.g.

IMG_1618.jpg

[bfollowell]

That's really strange then, because that's what I've done, with several combinations of my drives. and I can't seem to get my 520 to ever recognize that there is an actual, physical second drive connected. It always does the swap floppy thing like it thinks there is only one drive connected. Even though all three drives work alone, regardless of which of the two cables I use.

And that is how I have mine hooked up. 520STM floppy out to in port of Drive A. Out port of Drive A to in port of Drive B.

Is there anything different about the cable or are they the same? Assuming they're the same, is there a different line used when using a Drive B, that wouldn't be used when using with Drive A? If there were, and that line was bad in one of my cables, that would explain why both seem to work just fine when using with one drive, but not with two. I think they both failed to recognize Drive B though, and it would be odd to have two bad cables.

I'm at a loss.

I'll try playing around with them again after dinner and pay extra special attention when I'm swapping cables, and make certain I'm trying all possible combinations and plugging into the right ports.

Either way, you're saying it shouldn't take anything special. No messing around in the software. No mounting drive letters. Just plug them in correctly and they work?

Thanks!

[stephen_usher]

Yes, they just work. The line swapping is done on the SF314 controller board between the IN and OUT ports by connecting the drive select 1 from the input to the drive select 0 line on the output.

[bfollowell]

I have one cable that shows no drives. When I boot with any of my "real" drives connected using that cable, the 520 boots and no floppy icons are shown, so it isn't picking up the drives at all. Strangely enough, if I put a Gotek in any of those drives and boot with that same cable, the system recognizes the Gotek as drive A and the system boots fine.

I have no idea why that cable would work with a Gotek, but not with a real Atari drive, but it definitely seems like some sort of cabling issue.

I'll have to order a new cable and check things out again.

Thanks again for your help.

[tzok]

Each FDD/Gotek should be internally set to ID0 (DS0) in order to work correctly. The ID change is done between IN and OUT ports of the SF314.