"Matt Mc_Carthy" wrote to "MIKE ROSS" (05 Jun 03  23:51:48)
 --- on the topic of "IDE twins."

 MM> Haven't heard of anything like that!

Here are a pair of snippets on the topic. I think the problem is with
the definition of a couple of lines on the data cable where they placed
critical lines side by side and could in some setups have crosstalk
problems. In the early days of IDE we would actually slit the cable to
separate the offending lines and solved the problem in the field.

 Mike
 ****


" If a UDMA/66 or UDMA/33 drive is installed in a
  system with a maximum performance of PIO Mode 4 then the
  drives are limited to the system PIO Mode 4 performance.
"


> Area: Computer technical conference
> Date: 11 Aug 98  19:42:32
> From: Russell Brooks
> Subj: Re: Windy Messages
>
>  MM> One reader here just a few weeks ago was running UDMA drives on
>  MM> two meter cables, and was claiming no problems.
>
> 2 UDMA drives - one on the end of a 1.5metre cable on the primary IDE
> controller and the other on the end of another 1.5 metre IDE cable on
> the secondary controller.... 3 metres of cable between drives all up.
> Works well with no corruption IF BOTH drives are UDMA.
>
> Now if I use my WD4.3gig UDMA and my WD3.1gig mode4 together on the
> same cables, then I get corruption...even data from a CD gets corrupt
> on its way to the drive.
>
> Seems the drives MUST be ALL either UDMA or MODE4 to keep the
> corruption at bay, in my experience (so Far)


... The UARTs won't take this speed much longer, Captain!
--- Blue Wave/DOS v2.30