Browse Prior Art Database

Multi-Functional Control with a Single Line in a Parallel Processor

IP.com Disclosure Number: IPCOM000105271D
Original Publication Date: 1993-Jul-01
Included in the Prior Art Database: 2005-Mar-19
Document File: 4 page(s) / 134K

Publishing Venue

IBM

Related People

Blum, A: AUTHOR [+3]

Abstract

A parallel processor is described in which a single programmable signal line is used to control the communication between ports.

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

Multi-Functional Control with a Single Line in a Parallel Processor

      A parallel processor is described in which a single
programmable signal line is used to control the communication between
ports.

      Fig. 1 shows two of n satellite processors and their connection
by a crosspoint switch.  All n satellites are coupled via the port
function to a switch controller by a dedicated bus (S-bus)
transporting commands and control information for connect (and
disconnect) requests to estab lish (or terminate) interconnection
links.  The S-bus has a 1-byte bidirectional address bus, request and
grant lines, a status bus, and a number of control lines.  The switch
control function is divided into the matrix switch module control
(switch controller) and the link control distributed to the
satellite-attached port logic also using the S-bus.

      It is assumed that satellite A has been requested to
communicate with satellite B.  This is initiated by putting an
instruction into the mailbox of satellite A.

      The BSA (Blue Bus to Switch Adapter) function (Fig. 1) then
reads the mailbox with the command, the satellite B address and the
data (or, depending upon the instruction, a storage address for the
data to be exchanged) and starts executing the following steps:

o   The attached BSA function sends a connect command to the port
    function via a switch cable (suitable for long-distance
    connections).
o   Then, the port tries to contact the switch controller via the
    S-bus by activating a request line.  This is answered by a grant
    signal after a number of cycles (depending upon the port priority
    and the number of satellites trying to get the S-bus at the same
    time).
o   After grant, the S-bus is reserved one time frame for sending the
    connect command with the addresses of satellites B and A.
o   The port of satellite B responds directly with its status
    information to the bus master (port of satellite A) using a
    dedicated status bus.  The switch controller watches the
    addresses as well as the status information being responded and
    establishes a link between the two satellites in the case of a
    good status.
o   Then, the communication between the two satellites can start.

      The timing of the descr...