Possible to use "External Floppy (DF1)" as a DF0 ?

dougal

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I installed a Gotek in my A500 and it works great, but I do NOT want to butcher the case to fit it inside. I also don't want to spend any more money on adapters and mods.

Is there a way to make the external drive port at the back act as if it was a DF0: so that I can mount the Gotek inside an external floppy drive case ?
 

pms

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If you are using kickstart 2 rom, you can select external drive as bootdisk by pressing both mousebuttons after resetting the amiga. (This is how I boot games from external 5 1/4" diskdrive)
 

dougal

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That sounds difficult and risky :(

Yes, swap the drive select pins for DF0: and DF1: on the CIA chip.

- - - Updated - - -

I'm using dual kickstarts 1.3 and 2.04

But how you say, I think not all games will work especially the ones which are "NDOS/Not initiliazed"
If you are using kickstart 2 rom, you can select external drive as bootdisk by pressing both mousebuttons after resetting the amiga. (This is how I boot games from external 5 1/4" diskdrive)
 

BLTCON0

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That sounds difficult and risky :-(

True, although not really that much.
It's the only real (low-level) way though. As you correctly guess, any game that has its own routines to access the drive (i.e. it 'hits the hardware directly') will not work with a software solution.

The signals are on the EVEN CIA (U 8 chip. Remove it, and CAREFULLY (slowly and steadily) lift pins 13 (select DF0: ) and 14 (select DF1: ) so they're at a right angle with the other pins (the pins can survive a few such bendings before they break off).

Take two short pieces of wire, strip the ends and tin them with solder.
Flatten one tinned-end on each wire by depressing it, and insert these ends on positions 13 and 14 on the socket.
Insert the CIA chip into the socket again, taking care that the inserted wires insulation doesn't prevent the firm insertion of the chip.
Solder wire from socket position 13 to the (now hanging) CIA pin 14. Solder wire from socket position 14 to the (now hanging) CIA pin 13.
The swap is now complete. Every DF0: request will be hardware-routed to the external connector, and every DF1: request to the internal connector.

Wires length should be short, but not so short that it makes soldering them to the pins difficult.
 
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roy_bates

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That sounds difficult and risky :-(

True, although not really that much.
It's the only real (low-level) way though. As you correctly guess, any game that has its own routines to access the drive (i.e. it 'hits the hardware directly') will not work with a software solution.

The signals are on the EVEN CIA (U 8 chip. Remove it, and CAREFULLY (slowly and steadily) lift pins 13 (select DF0: ) and 14 (select DF1: ) so they're at a right angle with the other pins (the pins can survive a few such bendings before they break off).

Take two short pieces of wire, strip the ends and tin them with solder.
Flatten one tinned-end on each wire by depressing it, and insert these ends on positions 13 and 14 on the socket.
Insert the CIA chip into the socket again, taking care that the inserted wires insulation doesn't prevent the firm insertion of the chip.
Solder wire from socket position 13 to the (now hanging) CIA pin 14. Solder wire from socket position 14 to the (now hanging) CIA pin 13.
The swap is now complete. Every DF0: request will be hardware-routed to the external connector, and every DF1: request to the internal connector.

Wires length should be short, but not so short that it makes soldering them to the pins difficult.

years ago,there was a board made that went into the cia socket to do exactly that(cant remember who used to make them)
it was simply a pcb with a socket on it with fly leads to a switch to select df0 or df1 internal /external,you removed the cia and transplanted it to the pcb's socket and plugged the whole lot back in and off you went.
it was for the 500.
 
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BLTCON0

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No, since it doesn't have a PCB, but it obviously does the same job.

This one seems to have been constructed using two piggybacked sockets (to allow easy breaking of connections for pins 13 and 14).
Lower socket goes into CIA socket on the motherboard.
Upper socket goes into lower socket, except for pins 13 and 14.
CIA chip goes into upper socket.
Positions 13 and 14 between sockets are interconnected via a switch to allow straight (13 lower-13 upper & 14 lower-14 upper) or crossed (13 lower-14 upper & 14 lower-13 upper) wiring selection.
 
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roy_bates

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to be honest this would be very simple to do,even with a pcb.a proto or vero board will work,a socket pin headers and a dual pole switch and some wire.

all the wiring is on the dual pole switch for switching the signals over or passing them through,if you get stuck i can draw a rough diagram to show you how to wire it.
 
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Snoozy

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I bought one of these http://www.ebay.co.uk/itm/NEW-Gotek...pt=UK_VintageComputing_RL&hash=item19edb70554 and then in boot options, select df1 as boot disk - to try to force the external gotek to act as dfo:

Total waste of time, only around 20% of games work from the gotek, defeating the original purpose of the gotek. Far easier to dremel too little cuts on the 1200 white casing floppy enclosure and have gotek fitted in df0 as it was designed to.
 

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Yes I saw those and imagined they would be a waste of time & money... They are basically the exact same hardware any Amiga extarnal floppy drive has, minus the actually floppy drive.

No dremelling on my A500. For now (temporarily) I've removed the metal shielding and the middle rear case screw and passed the floppy ribbon cable and power cable out from the back of the case (between the top and bottom casing) and kept the Gotek externally. The internal original disk drive is still in there though its disconnected obviously.

Its much neater than removing the original drive and passing the wires from the drive hole in my opinion as I tried it and it looked messy.

Eventually i'll look into doing that mod where there Disk Drive port and be switched between DF0 or DF1.

I bought one of these http://www.ebay.co.uk/itm/NEW-Gotek...pt=UK_VintageComputing_RL&hash=item19edb70554 and then in boot options, select df1 as boot disk - to try to force the external gotek to act as dfo:

Total waste of time, only around 20% of games work from the gotek, defeating the original purpose of the gotek. Far easier to dremel too little cuts on the 1200 white casing floppy enclosure and have gotek fitted in df0 as it was designed to.
 
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SkydivinGirl

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I've been thinking about doing a remake of the ICD Shuffleboard. It allows you to remove the internal floppy drive ans assign the first external drive to DF0. This board plugs in between the Gary and the motherboard. The only problem is that I don't know which Amigas the board will work in. It will definitely work with the A500 and A2000.

Heather
 

BLTCON0

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I've been thinking about doing a remake of the ICD Shuffleboard. It allows you to remove the internal floppy drive ans assign the first external drive to DF0. This board plugs in between the Gary and the motherboard. The only problem is that I don't know which Amigas the board will work in. It will definitely work with the A500 and A2000.

Heather

The board plugs between Even CIA and the motherboard, not Gary.
On the A2000 it will work just as fine as on the A500/A1000, but DF0: will map to the second internal and not to the first external drive.
 

DonutKing

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I had the idea of making a DF0/DF1 switch that changed when you held down a mouse button on startup - similar to how some of those kickstart switchers work.
The idea was that you could hook up the gotek externally, keep the real floppy drive inside the amiga, and switch between them by holding down a button when you power on.
However I never found any info on how this was accomplished.
 

BLTCON0

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I had the idea of making a DF0/DF1 switch that changed when you held down a mouse button on startup - similar to how some of those kickstart switchers work.
The idea was that you could hook up the gotek externally, keep the real floppy drive inside the amiga, and switch between them by holding down a button when you power on.
However I never found any info on how this was accomplished.

The theory is not very complicated - you'd want to use the reset signal available on a Gary pin (e.g. high to low transition) as a trigger to latch the state S (available on a CIA pin) of the left mouse button, and say /S=0 -> no swap and /S=1 -> swap, then you'd implement equations such as:

/SEL0_out = S*/SEL0_in + /S*/SEL1_in and
/SEL1_out = S*/SEL1_in + /S*/SEL0_in

using simple logic or maybe a PAL ('ins' are taken from the CIA chip pins, 'outs' are connected to the corresponding motherboard/socket pins).

Someone with more experience in electronics can certainly provide more detailed info.
 
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dougal

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I think someone should make these adapters. It will save so many Amiga 500/600s from being butchered.

Don't know if an A1200 solution is possible given that the chips are all soldered.
 

roy_bates

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I think someone should make these adapters. It will save so many Amiga 500/600s from being butchered.

Don't know if an A1200 solution is possible given that the chips are all soldered.

the 600's cias are soldered down too.
 

dougal

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I think someone should make these adapters. It will save so many Amiga 500/600s from being butchered.

Don't know if an A1200 solution is possible given that the chips are all soldered.

the 600's cias are soldered down too.

Oh yes. I forgot. Well I guess it will apply for an A500 and A1000 since A2000 does not really need one.
 
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