Browse Prior Art Database

Single In-Line Memory Module Identification Method for Personal Computers

IP.com Disclosure Number: IPCOM000105700D
Original Publication Date: 1993-Sep-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 108K

Publishing Venue

IBM

Related People

Dayan, RA: AUTHOR [+2]

Abstract

Described is a software implementation to enable expansion of single in-line memory module (SIMM) units by implementing an identification (ID) nomenclature for personal computer (PC) memory devices. The SIMM ID implementation is recorded on an associated diskette file enabling SIMM expansion and to provide important SIMM characteristics to a PC system memory controller.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 51% of the total text.

Single In-Line Memory Module Identification Method for Personal Computers

      Described is a software implementation to enable expansion of
single in-line memory module (SIMM) units by implementing an
identification (ID) nomenclature for personal computer (PC) memory
devices.  The SIMM ID implementation is recorded on an associated
diskette file enabling SIMM expansion and to provide important SIMM
characteristics to a PC system memory controller.

      In prior art, PC systems used 72-pin SIMM technology which had
4-pins dedicated for SIMM ID purposes.  This enabled sixteen
different types of SIMMs to be installed in a PC.  With new SIMM
technologies coming on line, ID-type designation is found to be
required beyond the prior art sixteen.  The concept described herein
provides for ID of additional SIMM types and accommodates any future
changes in SIMM technology.

      The method of SIMM ID to accommodate the additional SIMM types
is designed for SIMMs which have sixteen detect pins constructed into
the SIMM for identification purposes.  This allows 65,536
combinations of SIMM characteristics to be identified, including one
ID to indicate no SIMM is present.  The SIMM ID method is designed to
be used in conjunction with the set configuration utility (SCU)
program so as to access a diskette file representing the
characteristics of a SIMM.  For example, if a SIMM is being
introduced that is not accurately represented by any previously
released SIMM, an ID would be obtained from a controlling
organization and an appropriate ID memory SIMM file (MSF) would be
created and shipped with the SIMM.  The MSF information would be
recorded on a diskette and used by all identical SIMMs, regardless of
manufacturer.

      The MSF contains keywords that describe the characteristics of
the SIMM and defines characteristics, such as:  access speed, page
mode access, static column access, multiplexed, density, ECC, parity,
row, data width, column, redrive and low power/standby rate.  The
existing PC memory configurator, included in the set configurator, is
expanded to allow it to process the MSF designation.  It has the
ability to access all present SIMM IDs, to match them with the
appropriate MSF, and to interpret the contents in order to develop
the configuration information required by the memory controller.

      The initial system configuration of the SIMM ID involves the
use of a system reference diskette (SRD) and is actuated by the user
during the system set-up phase.  The user is prompted to insert the
SRD in a specific drive location, or if the system contains a system
partition on a hardfile, the system partition will be booted.  In
either case, the user will be presented with a menu, or the user can
choose an automatic configuration option.  At this point the SCU
queries the hardware as to its capabilities and the presence or
absence of features.  Set-up of all hardware features, except memory,
are not perti...