Can a floppy selector switch & external<>internal Gotek cable work together?

[Starglider 2]

Hi guys, I'm a little stuck and hope you can clarify.

Objective:
I have a Gotek drive. I want to connect it to the A500 external disk drive port, but have it behave as DF0.

What I bought:
1. http://www.ebay.ie/itm/272363110859
2. https://drive.google.com/open?id=0Bw...C1DekVWdWkyZGs from @DjCook on Amibay

When the switch is installed according to the manual, and the Gotek connected to the external disk drive port, I can't get the Gotek to appear as DF0.

The best I can get on workbench is an icon that says:

💾
DF0:????

If I try to boot from it I get:
Not a DOS disk

The disk image worked fine before.
The Gotek jumper is set as S0 but I've tried S1 too.

Any ideas? Are these cables not compatible with each other?

Thanks!!

[idrougge]

Does the Gotek appear as DF1?

[Starglider 2]

Originally Posted by idrougge

Does the Gotek appear as DF1?

Yes, it seems no matter which way the switch is, the Gotek is DF1. If I put the switch one way, I get the DF0:???? but Gotek still DF1. If I put it the other way, I get a working floppy in my real disk drive as DF0 and the Gotek still DF1. So the switch doesn't switch, when used with the external cable and external Gotek.

[idrougge]

The external Gotek solution I've seen before had at least one IC on an adapter board and not just a bare cable. Can't tell whether that would interfere, though.

[Starglider 2]

What I have done is install the DIP socket on the Even CIA as per the switch's instruction manual.

What I have not done is modify what the external cable says to do because the switch seemed to take care of Even (presumably):


And I haven't put a jumper on the floppy pins because I want to keep the mechanical drive attached and simply switch it from DF0<>DF1 when needed:

[amigoun]

I recently made myself similar cable and adapter and it works as it should, so possibly there could be a hardware related matter. Check if the bootselector switch have wires connected to 13th and 14th pin of the sockets, and if all the wires are well connected (these things are fragile).

[Starglider 2]

Originally Posted by amigoun

I recently made myself similar cable and adapter and it works as it should, so possibly there could be a hardware related matter. Check if the bootselector switch have wires connected to 13th and 14th pin of the sockets, and if all the wires are well connected (these things are fragile).

Everything looks good.

Assuming you're using the Gotek:
1. Is the Gotek jumper set to S0 or S1?
2. When you flick the switch can you use external Gotek as DF0 and internal floppy as DF1? @DjCook mentioned this isn't possible but I thought it was.

Thanks!!

[amigoun]

1. Gotek is set to S0.
2. Yes, when external Gotek is DF0 internal drive is invisible. Amiga sees only Gotek.

[Starglider 2]

Originally Posted by amigoun

1. Gotek is set to S0.
2. Yes, when external Gotek is DF0 internal drive is invisible. Amiga sees only Gotek.

And when you flick the switch the other way?

Could you post pictures of your modifications and cable please?

Thanks!!

[ikonsgr]

Hi, i'm the guy who made the external gotek cable, and i can say that gotek is wired with SEL1B signal, meaning as DF1. The "hack" i propose is to disable internal drive (that's why you need to bend over the CIA pin) and connect the SEL1B signal to SEL0 through the jumper on the 34pin floppy connector.
Now, i believe i have a "theory" for why you can't use BOTH gotek and internal drives in reversed positions (external gotek as DF0 and internal drive as DF1), it has to do with the "motor enable" signal. You see, amiga offers 2 different pins/signals for drive motor control, one is exclusively for DF0 (motor0) and the other is for external drives (motorX) . The "problem" is, that motor0 exists ONLY on the internal floopy connector, and motorX exists ONLY on the external. When amiga enables the DF0 drive it also enables the motor0 signal.
As Gotek drive doesn't have a motor, it doesn't use any motor signals, so it can work either as DF0 or DF1 depending exlusively on the wiring of the SEL signals. BUT, the internal floppy drive is a real drive so it needs the "motor enable" signal. When you reverse the selection signals for DF0 and DF1, and amiga enables the DF1 drive, it enables the "motorX" signal, which exists ONLY on external drive, so, the actually internally connected floppy drive, never gets the signal to enable it's motor (because this signal goes exlusively on external connector)! This will probably produce a "bad disk" error, because although the drive seems ready and appears correctly in workbench, it doesn't get any disk data because of the disable motor!
So, if the adapter you are using reverse only the "SEL" signals, and not "Motor enable" signals too, you will not be able to use both gotek and internal floppy drive in reversed positions.

[idrougge]

That's a thorough explanation, and shame on the person who made that switch.

[Jope]

The motor signal gets made into motor0 / motorX based on which select comes out of the CIA. Swapping the SELs between the CIA and socket is enough to get it working correctly.

Per default, all Amiga floppy mechanisms are jumpered SEL0, also for every old external drive I've seen so far. It's the external drive enclosure's electronics that routes the correct select from the Amiga to the mechanism and forwards the remaining select signals onwards to the daisy chain connector.

[eXeler0]

I'll just add to the conversation that I have an internal GoTek + external Floppy Drive with AmigaKit's DF0/DF1 switch and that combo works fine (in my A500 with socketed CIA chips (Even CIA replaced with modified version)

But... I've considered adding a External Gotek to the A1200 and use it as DF0 with a Switch. But that would be a quite different hack, wouldnt it?
Saw this thread..
http://www.amibay.com/showthread.php...as-a-DF0/page3
(Done by a different guy from Greece? Or..?)

[ikonsgr]

Originally Posted by Jope

The motor signal gets made into motor0 / motorX based on which select comes out of the CIA. Swapping the SELs between the CIA and socket is enough to get it working correctly.

No, it's not exactly like this, because although the CIA chip as you said, swaps the "motor enable" signals according to the SEL signal, there is NO motorX signal that goes to the 34pin internal floppy connector! So, when you make the swap, and DF1 drive is enabled, the "MotorX enable" from CIA chip, will go ONLY to the external connector, and of course the internal floppy drive, although it will be selected as external, it's motor will NOT start!

[Jope]

Originally Posted by ikonsgr

No, it's not exactly like this, because although the CIA chip as you said, swaps the "motor enable" signals according to the SEL signal, there is NO motorX signal that goes to the 34pin internal floppy connector! So, when you make the swap, and DF1 drive is enabled, the "MotorX enable" from CIA chip, will go ONLY to the external connector, and of course the internal floppy drive, although it will be selected as external, it's motor will NOT start!

Perhaps I didn't properly understand what is being swapped here. If it is sel0 and 1 between the socket and the cia chip, it would still work ok as sel1 on the cia would become sel0 on the motherboard.

[ikonsgr]

Originally Posted by Jope

Perhaps I didn't properly understand what is being swapped here. If it is sel0 and 1 between the socket and the cia chip, it would still work ok as sel1 on the cia would become sel0 on the motherboard.

Yes, and along with that the motor0/motorX signals will also swapped. The problem is that ,there is no PHYSICAL signal/pin of the motorX that goes to the internal floppy drive connector : http://www.l8r.net/technical/t-diskdrive.shtml

So, the only way to make both externally connected gotek and internal drive work together, is to swap the motor enable signals as well. This way, the "motorX enable" from CIA will go to the motor0 on motherboard, and 99% chances are, you will have a perfect working internally connected disk drive as DF1!

[Starglider 2]

Originally Posted by ikonsgr

Yes, and along with that the motor0/motorX signals will also swapped. The problem is that ,there is no PHYSICAL signal/pin of the motorX that goes to the internal floppy drive connector : http://www.l8r.net/technical/t-diskdrive.shtml

So, the only way to make both externally connected gotek and internal drive work together, is to swap the motor enable signals as well. This way, the "motorX enable" from CIA will go to the motor0 on motherboard, and 99% chances are, you will have a perfect working internally connected disk drive as DF1!

Thanks so much for explaining what the issue might be.

It's not exactly straightforward, but from where I am now (switch connected to EVEN CIA, Gotek connected externally) what should I do right now?

[Jope]

Originally Posted by ikonsgr

Yes, and along with that the motor0/motorX signals will also swapped. The problem is that ,there is no PHYSICAL signal/pin of the motorX that goes to the internal floppy drive connector : http://www.l8r.net/technical/t-diskdrive.shtml

So, the only way to make both externally connected gotek and internal drive work together, is to swap the motor enable signals as well. This way, the "motorX enable" from CIA will go to the motor0 on motherboard, and 99% chances are, you will have a perfect working internally connected disk drive as DF1!

.. and we're still talking about the A500?

Please give me a pinout or schematic screenshot that shows which pin on the CIA is MTR0 and which pin is MTRx?

[eXeler0]

Originally Posted by Starglider 2

Thanks so much for explaining what the issue might be.

It's not exactly straightforward, but from where I am now (switch connected to EVEN CIA, Gotek connected externally) what should I do right now?

I understand that you already have a bunch of stuff which you want to start using, but is there a particular reason why you couldn't choose an internal GoTek and standard External Floppy Drive? With that config the Even CIA switch works just fine.

If you worry about having to damage your case there's always this extension board that will allow you to keep your case unmodified.
http://www.ebay.com/itm/The-new-Gote...YAAOSwg3FUjzse

[Starglider 2]

Originally Posted by eXeler0

I understand that you already have a bunch of stuff which you want to start using, but is there a particular reason why you couldn't choose an internal GoTek and standard External Floppy Drive? With that config the Even CIA switch works just fine.

If you worry about having to damage your case there's always this extension board that will allow you to keep your case unmodified.
http://www.ebay.com/itm/The-new-Gote...YAAOSwg3FUjzse

It's an option but I like to keep the A500 as stock as possible, and avoid unnecessary expense on top.

Thanks!!