Browse Prior Art Database

Local Main Store Bus with Separately Controlled Command and Data Portions

IP.com Disclosure Number: IPCOM000106519D
Original Publication Date: 1993-Nov-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 2 page(s) / 58K

Publishing Venue

IBM

Related People

Baldus, DF: AUTHOR [+10]

Abstract

Disclosed is a system of independent data and command/address busses. A set of rules to allow the independent busses to communicate coherently is also described. This system of busses and rules allows a greater utilization of the command/address bus as well as the data bus.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Local Main Store Bus with Separately Controlled Command and Data Portions

      Disclosed is a system of independent data and command/address
busses.  A set of rules to allow the independent busses to
communicate coherently is also described.  This system of busses and
rules allows a greater utilization of the command/address bus as well
as the data bus.

      The Command/address bus (hereafter called just command bus) and
the data bus portions of a main store bus are completely separate of
each other in a usage sense.  One must arbitrate and win the command
and data bus independently of each other.  In addition a bus unit can
be connected to more than one command or data bus.  Being connected
to more than one command bus allows a bus unit to send a command on
any bus that connects to the destination.  Likewise, being on more
than one data bus allows one to send the data on any data bus that is
connected to the destination.

      The command contains some special routing information in
addition to the destination of the command.  This information is the
command source and a command ID number that allows a response command
to be properly routed back and matched up to the source.  The data
has no source, destination, or ID numbers.  The source ID of the data
sender must be available from the data arbitration unit.

      There are problems caused by the the independent command and
data busses.  One problem resulting from the independent busses that
requires special consideration is the absence of a destination
identif...