🚀 go-pugleaf

In article <1992Dec10.003626.599@news.columbia.edu>, lasner@watsun.cc.columbia.edu (Charles Lasner) writes:
> In article <1992Dec8.210008.5888@ais.com> bruce@ais.com (Bruce C. Wright) writes:
>>In article <1992Dec7.222607.3388@newstand.syr.edu>, amichiel@rodan.acs.syr.edu (Allen J Michielsen) writes:
>>> 
>>>  If there is the DEC DOS 2.11 version available, usually for free, and the
>>> system isn't compatible, why would anybody buy a dos 3.1 or code blue.
>>
>>Several reasons:
>>
>>    1) DOS 3.1 can handle larger hard disk drive partitions.  DEC DOS 2.11
>>	couldn't handle partitions larger than 8MB as I recall;  DOS 3.1
>>	can handle up to 32MB.  This makes dealing with reasonable-sized
>>	hard disks more tolerable.
> 
> DECmate MS-DOS 2.11 can handle up to about 11 MB bootable partitions and
> 32 MB non-bootable partitions.  I suspect that Rainbow MS-DOS does about
> as well, but few Rainbows have enough disk present to test this out.

I'm _quite_ sure that DEC MS-DOS 2.11 for the Rainbow did not support 32MB
partitions, but I don't remember exactly where the cutoff was.  I _think_
it was 8MB -- I distinctly remember that when we had 20MB drives on the
Rainbow running DOS 2.11, we had to break them up into several partitions;
3 as I recall.  The DECmate MS-DOS apparently was less crippled.

> It is noteworthy that there at least two MS-DOS 3.10 versions, only one from
> Suitable Solutions.  The other is from DEC itself.

The DEC version of MS-DOS 3.1 was an internal project that was never
officially available outside of DEC.  There was never an end-user version
of it marketed and there is no documentation available.  The Suitable
Solutions MS-DOS 3.1 was derived from the DEC version (DEC licensed the
rights to the code to Suitable Solutions under some undisclosed licensing
arrangement), and was so far as I know the only version of DOS 3.1 that
was actually _sold_ to end-users.

>>You can use most drives with an ST506 interface on the Rainbow.  So you
>>can use an ST-225 as a 5 or 10MB drive, though I'd rather use it as a
>>20MB drive :-).  The Rainbow does support that, although you do have to
>>get one of the PD disk formatting programs for it like WUTIL (the standard
>>DEC disk formatting program didn't support anything but DEC drives, and
>>the ST-225 doesn't have the same geometry as any DEC drive).
> 
> Wrong; the ST-225 *is* the RD-31.  It is standard on DECmate III+ and often
> found in DM II.

I do not believe that the Rainbow ever officially supported that drive;
certainly the standard DEC hard disk drive formmater did not know about
it.  I didn't necessarily mean that the drive wasn't used in _some_ DEC
machines, but it wasn't supported on the Rainbow and the Rainbow software
knew _nothing_ about it.  You need third-party software in order to use it.
I think the point was that by the time the ST-225 was out, DEC had already
effectively given up on the Rainbow.

Bruce C. Wright