"mcguire@neurotica.com" "Dave McGuire"

>On February 24, Michael Sokolov wrote:
>>    Dear Allison,
>>
>> > That concept is a fantasy in your mind only.  There is no blocking I know
>>                                                                      ^^^^^^
>> > of save for unimplemented/undocumented capability.
>>   ^^
>>
>>    Therein lies the rub. :-) I'm _SURE_ that the same driver could be used
>
>  Michael...are you REALLY trying to argue this point with someone who
>WORKED AT DEC, someone who WORKED ON THAT CODE?  That's a little
>silly, don't you think?

Very true.

And in fact the VS2K manual does make it clear that there are interactions
between the NCR and the disk controller (e.g. they share buffers). So
the uVAX 3100 VMS DK driver cannot be used unmodified and neither can the
console VMB driver.

There is also the minor fact that at the time that the uV2K/VS2K shipped the
uVAX 3100 didn't exist and neither did its console. So there was no SCSI disk
driver around in any form. Since the NCR chip was just used as a cheap way to
interface to an existing low-end tape unit, there was no need to write a full
blown SCSI driver; all that was done was the bare minimum to get the *required*
functionality.

The uVAX/VS 2K machines were pretty successful in their day. If they had
shipped a year or two later that might have harmed sales significantly :-) 

As a programmer I can guarantee that if you wait for someone to produce code
they are entirely happy with and which fully exploits the potential of the
hardware you'll never see the machine ship :-) :-)

Antonio

Antonio Carlini                            Mail: carlini@marvin.enet.dec.com
DECnet-Plus for OpenVMS Engineering
Digital Equipment Corporation              Worton Grange, Reading, England