Author Topic: Why are some wires on floppy disk drive cables reversed?  (Read 1385 times)
Fluorescent05
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Zack


Why are some wires on floppy disk drive cables reversed? « on: August 07, 2019, 11:05:39 PM » Author: Fluorescent05
I have a floppy disk cable where some wires are reversed. Why is this? Should I connect the drive to the side where no wires are reversed and the middle to the motherboard or the side where they are reversed?
Logged

I can't pretend a stranger is a long awaited friend. -Neil Peart

icefoglights
Member
*****
Offline

Gender: Male
View Posts
View Gallery

ITT Low Pressure Sodium NEMA


GoL
Re: Why are some wires on floppy disk drive cables reversed? « Reply #1 on: August 08, 2019, 03:00:07 AM » Author: icefoglights
The twisted end determines the drive designation.  The drive on the far end of the twist would be A and on the near end of the twist would be B.  The drive should be placed on the far end of the cable.  That sets it as the A drive, and places the drive's terminating resisters on the far end of the cable, where they are needed.
Logged

01010010 01101111 01100010 01100101 01110010 01110100

Fluorescent05
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Zack


Re: Why are some wires on floppy disk drive cables reversed? « Reply #2 on: August 08, 2019, 07:56:03 AM » Author: Fluorescent05
The twisted end determines the drive designation.  The drive on the far end of the twist would be A and on the near end of the twist would be B.  The drive should be placed on the far end of the cable.  That sets it as the A drive, and places the drive's terminating resisters on the far end of the cable, where they are needed.
Thank you!
Logged

I can't pretend a stranger is a long awaited friend. -Neil Peart

Rommie
Administrator
Member
*****
Offline

Gender: Female
View Posts
View Gallery

Andromeda Ascendant


Re: Why are some wires on floppy disk drive cables reversed? « Reply #3 on: October 28, 2019, 04:44:43 PM » Author: Rommie
Floppy disks, now that takes me back..! Don't use them these days, but I do still have a USB 3.5" drive in the desk drawer should I ever need it.
Logged

Ria (aka Rommie) in Aberdeen
Administrator, UK & European time zones. Any questions or problems, please feel free to get in touch :love:

"What greater gift than the love of a cat..?" - Charles Dickens
*** No smiley-only replies, please ***

Medved
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Re: Why are some wires on floppy disk drive cables reversed? « Reply #4 on: October 28, 2019, 05:53:32 PM » Author: Medved
Originally there were "A/B" switches on the drive units (similarly as "master/slave" on IDE HDDs or CDROMs way later in time, but the floppy drives needed more than just a single jumper - often a cause of wrong, even inconsistent setting), but then the twisting cable trick came along. Consequently all drive makers get rid of the jumpers and permanently configure the drives as "B" and rely on the (then standard) twisting to remap it on the cable end to A... This got rid of the misconfiguration problems (if not all jumpers were set consistently to either A or B or some lost contact, the system did not work and all bios build in floppy diagnostic returned hard to debug nonsense).
Logged

No more selfballasted c***

Print 
© 2005-2024 Lighting-Gallery.net | SMF 2.0.19 | SMF © 2021, Simple Machines | Terms and Policies