From: utzoo!decvax!harpo!npoiv!npois!cbosgd!djb
Newsgroups: net.micro.pc
Title: Sritek MicroCards & XENIX - more info
Article-I.D.: cbosgd.3068
Posted: Wed Feb  2 10:35:49 1983
Received: Thu Feb  3 07:32:42 1983


	I've had several request for more information on the Sritek 
products, particularly the 68000 MicroCard, so I've decided to dig into 
my literature and post a more detailed description.  Much of what follows
is taken directly from Sritek's journal FOREFRONT. (vol.1, no.1, Nov/Dec
1982).

	"The building blocks for the Sritek products consist of the PC
VersaCard and the processor MicroCards with various operating systems,
programming languages and commercial applications.  The VersaCard is a
single-slot expansion memory for the IBM PC.  In a stand-alone mode,
it is a 256K byte expansion memory.  The memory can be easily expanded
from 256K to 512K bytes by mounting a RAM Module.  A processor MicroCard
can also be mounted on the VersaCard which effectively changes the
"personality" of the IBM PC.  The VersaCard is dual-ported memory; to
the MicroCard it appears as a 16-bit memory and to the 8088 it appears
as an 8-bit memory.  When a processor MicroCard is mounted on the
VersaCard, and the standard Sritek software is used, all application
programs are automatically redirected to the MicroCard which acts as the
Main Processing Unit (MPU).  All input and output chores, such as
communication with the CRT terminals, the disk drives and the printer are
handled by the PC; the 8088 processor functions as Input/Output Processor
(IOP) and operates in parallel with the MPU.  This type of task-partitioning
provides additional performance for I/O-demanding applications such as
multi-user and multi-tasking systems or systems with local area network
facility."


	__________________   ____________________________________
       /                 /  /                                    /
      /   RAM Module    /  /             MicroCard              /
     /  (256K memory)  /  /(Z80B,8086,68000,iAPX-286, or 16032)/
    /_________________/. /____________________________________/.
      .  .          .  .   .  .                             .  .  
      .  .          .  .   .  .                             .  .  
      .  .          .  .   .  .                             .  . 
      . _________________________________________________________
      ./ .          .  .   .  .                             .  . /
      /             .      .         PC VersaCard           .   /
     /.             .      .        (w/256K memory)         .  /
    /__________________________________                _______/
                                      /_______________/
				           IBM I/O
				      Channel Interface

Figure 1: The RAM Module and MicroCard connect to the PC VersaCard
	  through three special back-to-back bus connectors, forming
	  a very compact unit that takes only one PC expansion slot.

	The 68000 MicroCard brings UNIX System II to the PC via the
enhanced XENIX Ver 3.0 (by Microsoft) operating system.  Features
include real-time clock, message registers for inter-processor 
communication, paged-memory management that supports up to 16 users
and hardware protection for system programs from user processes. Sritek
plans to support the 68010 virtual memory processor in the near future.
Currently, 8 10 and 12.5 MHz 68000 are available.  (The leadless chip
carrier (LCC) 68000 package is used to conserve board real estate.)

	In case you'd like to contact Sritek directly, here is their
address and phone number:

			Sritek Inc.
			3637 S. Green Rd.
			Cleveland, Ohio 44122
			Phone: (216) 292-0011

	Personally, I was very impressed.  Sritek seems to have done
everything right as far as I can tell.  Unfortunately, I didn't get the
chance to play with it very much, so I don't know how well some parts
work (the interaction between 68000 and 8088 for example).  Although
I don't know specific pricing details, Sritek was quoting <$6000 for
a IBM PC + 68000 MicroCard + XENIX.  When I told them about the upcoming
price reduction in the PC, they were excited, since that would bring
their quoted minimal system price even lower.  I don't know how much they
were allowing for the PC used so I don't know how much of the $6000 can
be trimmed away through judicious purchasing techniques, nor how much
it costs to upgrade a PC if you've already got one.

	As for XENIX, it appears I was very wrong in asserting that it 
doesn't have the C-shell and other Berkeley goodies.  In fact, XENIX 
includes quite a variety of Berkeley software, including csh, ex/vi, more, 
tset, finger, ctags, mkstr, xstr, printenv, and gets.  Unfortunately, the
Sritek descrpition of XENIX makes no mention of these features, so I 
incorrectly assumed they weren't there.  Given this new information, I can
well believe that XENIX is the best of the UNIX-based systems. 

	Now if I can get some real price numbers out of Sritek, we'll 
have things pretty well covered. 

	If you have any more questions, let me know.

	David Bryant   Bell Labs   Columbus, OH   (614) 860-4516
	(cbosg!djb)