Date   : Tue, 06 Jul 2004 13:18:15 +0100
From   : Richard Gellman <splodge@...>
Subject: Re: Acorn Winchester unit

Jules Richardson wrote:

>On Tue, 2004-07-06 at 10:31, Richard Gellman wrote:
>
>  
>
>>Well now. I have something you may well be interested in.
>>
>>A while back, I construted a device consisting of a butchered parallel 
>>cable, a 50-way SCSI ribbon, and a 25-way D connector. I also put 
>>together some DOS software to use it. It can connect to an ADFS 
>>formatted drive on a SCSI interface, and using very basic commands 
>>extract the information thereof, and even skips over the "free spaces".
>>    
>>
>
>How did you manage that then? I had a look at this a few weeks ago and
>the real problem is lack of output lines on the parallel port (assuming
>8 bit transfers anyway). 8 bits are needed for bidirectional data,
>whilst the SCSI 'incoming' control lines can make use of input control
>lines on the parallel port, so that bit's easy. 
>  
>
pfft. you're controlling the wrong thing.
8 data lines for the SCSI bus/SCSI ID select, then use the 
control/status lines on the parallel port to control the SCSI bus directly.

You'll probably find that termination is *required* on the SCSI device 
in question.

-- Richard