Regarding the drive termination, I distinctly remember pulling terminators on the middle drive in a two-drive setup...just like a SCSI chain. I don't know about new drives (because I don't usually have multiple drives in my machines now), but some more modern Teac drives have a termination jumper rather than a resistor DIP pack. -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Chuck Guzis Sent: Thursday, October 20, 2005 1:19 PM To: cctalk at classiccmp.org Subject: Re: PC floppy cable twists... On 10/20/2005 at 5:48 PM Jules Richardson wrote: It's actually pretty simple--there's only a single "motor on" line for the standard floppy pinout. IBM wanted to control drive motors individually. The only ways to do that are with individual drive cables or using the "twist" (or some modification of it) so that the individual drive motor enables are given different conductors in the cable. Other systems using "straight through" cables switched all drive motors on and off--and many consequently used drives with head-load solenoids. IBM's solution let them economize a bit on power-supply design and use a cheaper (and quieter) drive without the head-load mechanism. FWIW, IBM makes no mention of terminator removal or addition and I don't even recall if the standard 5.25" drive allowed one to play with termination. On one of the ISA floppy/hard controllers--I think it was DTC--you could add a third drive to the string using a special cable and a drive jumpered for DS0. (I'd have to check my doc files to get the rest of the details on the cable construction). Cheers, Chuck