Date   : Tue, 24 Aug 1982 13:13:17-EDT (Tue)
From   : Keith Petersen <w8sdz@BRL>
Subject: Concurrent CP/M and CP/M 3.0

I've heard recently that CP/M 3.0 is VERY close to being
released.  Several people have asked what new features it
will have, so I thought a review of a previous message on
the subject was in order.  My appologies to those who have
seen this before.

---

 #: 9043      Sec. 1 - Members
Sb: #Concurrent CP/M
    15-Mar-82  23:05:45
Fm: Digital Research 70007,1001
To: Sysop Charlie Strom 70210,104 (X)

Well, Charlie, this is going to take several answers, no doubt. RE: 8080 vs
8088, there are certain things that 8 bit machines make to difficult to
implement due to their 64k addressing limit.  Bank select is only a partial
answer to this, as inter-segment communication is still difficult.  Concurrent
CP/M is basically MP/M aimed at a single user, multi tasking.  The main
difference between reg. MP/M-86 and Concurrent CP/M is the virtual terminal
support. Our primary market place is not the enduser, as they are largely
incapable of interfacing complex interrupt driven systems (with the notable
exception of the "hacker" and systems programmer types, like myself...), but
rather is the OEM who sells systems.  Most of them are only interested in 16
bit systems for new products.  It is much easier to program an 8086 than a z80.
Have you ever tried to run something like WS under MP/M-80?  There is simply
too much overhead on an 8-bit system to do more than one job effieciently, most
programs are already CPU bound.

        The virtual console support allows one terminal to emulate several
(typically four).  If your actual console is memory mapped, something that is
easy to do on a system with a one megabyte address space, it will swap screens.
It can direct console input and output at disk files.  We are implementing it
on the IBM PC and the DisplayWriter initially (both systemsng memory mapped
video.)

        CP/M-80 Version 3 can be configured for bank select systems, giving a
63k TPA. It will support multiple sector/track buffers in the system bank, and
is generated by LINK-80, allowing the BIOS to be comprised of modules. 
Physical sector blocking and deblocking is handled by the BDOS, and the BIOS
may optionally implement multiple sector transfers, allowing consequitive
record transfers.  Perhaps even consequitive tracks.  It also supports bigger
disks (512 meg), faster directory access, optional date/time stamping... 
Etcetra.

                Type at you next conference...

                        -jrp