Junkbox CP/M system?

[Allison]

>
>Subject: Re: Junkbox CP/M system?
>   From: "Chuck Guzis" <cclist at sydex.com>
>   Date: Mon, 23 Apr 2007 22:16:08 -0700
>     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 24 Apr 2007 at 5:16, Ensor wrote:
>
>> The original IDE drives used 8-bit transfers (I had one in my first XT), 
>> even to this day there is still be a signal on the IDE interface to force 
>> the use of 8-bit mode.
>
>It's safe to say that there hasn't been an IDE drive manufactured 
>within the last 10 years that supports 8 bit data transfer mode.  
>Even many of those that claim to support it don't (probably just 
>vestigal "cut and paste" text).  I once went through my stack of 
>320MB and up 3.5" IDE drives and couldn't find a single one that 
>actually supported 8 bit PIO   
Same here and I have IDE drives all the way down to 10mb.  A few like
the WD TIDBIT80 seem to do it and none of my 2.5" drives from 160mb up
do it.  All of my Connor 21/40/60/80mb drives do not, nor do any of the 
collection of Seagates from 80mb through 500mb. I also have a potload 
of WD drives and I suspect a few smaller ones (20mb) but have 
found nothing documented that says they do and haven't tried them


> Mostly, IOCS16- is ignored on most 
>drives.  There was a considerable amount of debate in X3T10 when ATA-
>2 was being hammered out as to whether IOCS16-  should even be 
>included in the list of signals (it was removed when X3T10 defined 
>ATA-3).  It was reinstated in ATA-5 on request from the CF group.   

All the vendor docs I've seen seem to make IO16 an output as a notification
that the current transfer is 16bit.


>On CF, IOCS16- is honored--but it's not on any IDE  hard drive you're 
>going to buy today.

I've heard that was true of any drive over 500mb and have not seen anything
over 80mb that does. 

Me I keep saying if you really need the simplicity of 8b transfers and 
the low cost that comes from a surplus IDE drive just ignore the high 8bits
and enjoy it.  There's no harm from that.  So what if half the storage
is unused, likely the drive is large anyway.


Allison