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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: motorollin on January 04, 2008, 01:21:43 PM

Title: Rounded floppy cables
Post by: motorollin on January 04, 2008, 01:21:43 PM
Will a rounded floppy cable work with an Amiga 4000 floppy drive? I know the connectors will fit but I'm just not sure if the cables are wired up the same.

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moto
Title: Re: Rounded floppy cables
Post by: orange on January 04, 2008, 01:44:48 PM
yes, all you need is untwist them (http://www.amiga.org/gallery/index.php?n=1592)
Title: Re: Rounded floppy cables
Post by: motorollin on January 04, 2008, 01:51:37 PM
Thank you! Did you take the connector apart and recrimp it, or just cut the cable and re-connect the wires in the correct order?

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moto
Title: Re: Rounded floppy cables
Post by: orange on January 04, 2008, 02:33:10 PM
I opened and recrimped the connector, its easier and neater. All you need is two cuts, IIRC I included the GND lines on sides when doing the swap (so that the middle is wider).
Title: Re: Rounded floppy cables
Post by: motorollin on January 04, 2008, 02:56:40 PM
Quote
orange wrote:
I opened and recrimped the connector, its easier and neater.

Fair enough - I will try to do the same.

Quote
orange wrote:
All you need is two cuts

What do you need to cut if you re-crimp the connector?

Quote
orange wrote:
IIRC I included the GND lines on sides when doing the swap (so that the middle is wider).

Can you elaborate on this please? I don't understand what you mean.

Thanks again

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moto
Title: Re: Rounded floppy cables
Post by: orange on January 04, 2008, 03:56:32 PM
Well I didn't actually recrimp it. I used the same holes, if you understand me. (after opening connector) I had to cut the little plastic tape that holds all wires together so that they are split in three groups. Then just twist the middle group of wires. use colors to see which ones need to be untwisted, I think its pins from 10 to 16 according to this (http://www.hardwarebook.info/Internal_Diskdrive)

All odd wires are GND, if you include them in swap, the middle group becomes little larger and more 'stable'..
Title: Re: Rounded floppy cables
Post by: Oli_hd on January 04, 2008, 05:20:17 PM
Quote
Will a rounded floppy cable work with an Amiga 4000 floppy drive? I know the connectors will fit but I'm just not sure if the cables are wired up the same.


Ive just done it for my A4KT (It runs straight over the top of the CPU card so the round cables really are a must.
The board connector and the first connector was wired one to one so no problem there, the only thing is the lead I got was to short so I had to fix the last connector, I took the two top clamps off (one to hold a pull tab), both lost at least one tab so I glued it back on. :D
the rewiring was easy, the cable end was what seemed to be laminated with some plastic to keep it spaced, I removed the plastic cover from the pins I wanted to move over and then moved the wires over, tested it with the multimeter and plugged it in.

Worked first go :D

Oh and as for rewiring it, round cables seem to use multi coloured cabled so its as easy as match the wire colours.
Title: Re: Rounded floppy cables
Post by: motorollin on January 04, 2008, 05:31:08 PM
So just to clarify, the floppy cable (for an Amiga) should be connected straight through on all pins - right?

--
moto
Title: Re: Rounded floppy cables
Post by: Oli_hd on January 04, 2008, 05:57:15 PM
Quote
So just to clarify, the floppy cable (for an Amiga) should be connected straight through on all pins - right?


Correct (Thats what I did)
there is a jumper on the board to set the drive to the first or second drive where as PC drives twist the cable to signal the difference.
Title: Re: Rounded floppy cables
Post by: motorollin on January 04, 2008, 06:03:30 PM
Cheers guys.


Quote
Oli_hd wrote:
there is a jumper on the board to set the drive to the first or second drive where as PC drives twist the cable to signal the difference.


Couldn't I just leave the cable as is and then set the drive to DF1, and let the twist in the cable switch it back to DF0? Or is the twist not compatible with the Amiga?

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moto
Title: Re: Rounded floppy cables
Post by: Oli_hd on January 04, 2008, 06:34:06 PM
Quote
Couldn't I just leave the cable as is and then set the drive to DF1, and let the twist in the cable switch it back to DF0? Or is the twist not compatible with the Amiga?


Nope, sorry. The Amiga expects a flat cable, I dont know if there is a floppy select on the Amiga cable vs the PC one or what but crossing it over simply doesnt work.
Title: Re: Rounded floppy cables
Post by: motorollin on January 04, 2008, 06:43:21 PM
OK no worries. Doesn't seem like too big a job to take the connector apart and turn the twisted cables around.

Thanks again guys!

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moto
Title: Re: Rounded floppy cables
Post by: motorollin on January 08, 2008, 05:55:58 PM
Are the wires inside a ribbon cable numbered consecutively? IOW can I just count from wire 1 to wire 10, then count from there to wire 16 to find the wires I have to reverse?

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moto
Title: Re: Rounded floppy cables
Post by: motorollin on January 08, 2008, 07:21:41 PM
Never mind. I tried to take the connector apart and swap some of the wires, but it was so fiddly I lost my temper and the cable suffered a fate worse than death.

I'm going to get a PC floppy cable with the twist and crimp a male connector just after the twist, making a very short M-F floppy cable with a twist in it. This will then function as an adapter so a new, non-mutilated rounded floppy cable will work on the Amiga.

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moto
Title: Re: Rounded floppy cables
Post by: taunusand on January 08, 2008, 08:26:03 PM
Quote

motorollin wrote:
Are the wires inside a ribbon cable numbered consecutively? IOW can I just count from wire 1 to wire 10, then count from there to wire 16 to find the wires I have to reverse?

--
moto


Yep, I would also like to know that :-)
Title: Re: Rounded floppy cables
Post by: orange on January 08, 2008, 09:01:57 PM
yes, they are (if you look at opened connector); its easy to see which ones need reversing by comparing colours on both ends, in case you got fancy UV cable like me  :-)  
otherwise just use ohmmeter..
Title: Re: Rounded floppy cables
Post by: taunusand on January 08, 2008, 10:09:17 PM
Thanks  :-D

I would cut the wires and the solder them.

I think I would break the connector if I try to open it :roll:
Title: Re: Rounded floppy cables
Post by: motorollin on January 08, 2008, 10:11:40 PM
Quote
taunusand wrote:
I would cut the wires and the solder them.

I think I would break the connector if I try to open it :roll:

That's what I did. Then I accidentally stripped some of the insulation from one of the wires while trying to remove some sticky backing which is supposed to keep it in place. Then it wouldn't go back in to the crimp connector properly. Then I lost my temper and threw it away :roll:

I'm trying to find a source for 34 way male IDC connectors to crimp on to a PC floppy cable to make a little adapter.

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moto