Browse Prior Art Database

Micro Token Ring

IP.com Disclosure Number: IPCOM000113684D
Original Publication Date: 1994-Sep-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Day, LL: AUTHOR [+5]

Abstract

A reduced-function pseudo token ring bus used for non-critical local register reads and writes is described. The bus is designed to be used on a chip, although it could be adapted to a multichip module or even a board. The micro token ring is characterized by a master station and multiple slaves. In addition, the number of long global wires to read and write the non-critical registers is greatly reduced, but at the expense of greater real estate to create the stations.

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

Micro Token Ring

      A reduced-function pseudo token ring bus used for non-critical
local register reads and writes is described.  The bus is designed to
be used on a chip, although it could be adapted to a multichip module
or even a board.  The micro token ring is characterized by a master
station and multiple slaves.  In addition, the number of long global
wires to read and write the non-critical registers is greatly
reduced, but at the expense of greater real estate to create the
stations.

      This invention is a limited-function, low wire count pseudo
token ring inside the chip.  It could also encompass a multichip
module or card if so desired.  The ring connecting the stations would
be narrow bus, perhaps a nybble or byte wide.  It could be more or
less depending on the application.  One station of the ring would be
the master station and initiate all of the reads and writes to the
substations.  A substation would be placed on the chip (module or
card) near some auxiliary registers.  The substation would then look
for a register read or write to one of its registers.  If the read or
write was not to one of its auxiliary registers, then a cycle or so
later it would pass the read or write token on to the next station.

      When one of the substations sees a token for itself, it does
one of two following actions.  If it is a write, it grabs the
following data and puts it in a buffer while formatting it and then
writes it to the appropriate auxiliary register.  If it is a read,
the substation gets the data out of the appropriate auxiliary
register and puts it on the token ring a specified number of cycles
after the read token.

      There is only one token allowed on the token...